Exam 4 Flashcards
1
Q
What is another term for GastroIntestinal (GI) tract?
A
Alimentary canal
2
Q
What is the Alimentary canal?
A
The hollow tube that winds through the body and comes into contact with food material.
3
Q
Name the 7 structures that the GI tract contains.
A
Mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus.
4
Q
T/F: Accessory organs are necessary to digest food.
A
False! They assist in the digestion of food material, but are not necessarily required.
5
Q
Name the 6 structures the are considered Accessory Organs.
A
Teeth, tongue, gallbladder, salivary glands, liver, and pancreas.
6
Q
T/F: Food is considered to ENTER the body.
A
False! Food material is NEVER considered to enter the body.
7
Q
Why is food never considered to “enter” the body?
A
The alimentary canal is open to the external environment on both ends, so we say that food remains outside of body but passes through it.
So fucking stupid.
8
Q
What is the purpose of the Digestive System?
A
To ACQUIRE NUTRIENTS and WATER.
NOM NOM!
9
Q
What absorbs alcohol and aspirin?
A
The stomach
10
Q
What does the small intestine absorb?
A
Glucose, amino acids, and fats (lipids).
11
Q
What does the large intestine absorb?
A
Sodium, Potassium, acids, bases, Calcium, Magnesium, Iron, Vitamin B12, and water.
Basically, a bunch of ions, vitamin B12, and water.
12
Q
It is very important to note that absorbed nutrients from the digestive organs are passed into _______ of the digestive system and are then transported to the _________.
A
veins, liver
13
Q
Fats are absorbed by what? Then, what are they passed into? Where are they finally transported to?
A
Fats are absorbed through the small intestine.
They are passed into LACTEAL DUCTS of the lymphatic system.
Then, they are transported to the liver.
14
Q
What is the function of the Sigmoid Colon?
A
Serves as the storage site for feces.
P U
15
Q
What are the 6 essential food-processing activities of the Digestive System?
A
1) Ingestion
2) Propulsion
3) Mechanical Digestion
4) Chemical Digestion
5) Absorption
6) Defecation
I Park My Car Around DooDoo.
16
Q
What is Ingestion?
A
Taking food into the mouth.
17
Q
What does Propulsion consist of?
A
Swallowing (voluntary) and Peristalsis (involuntary movement of food).
18
Q
What 3 things do Mechanical Digestion consist of?
A
Chewing, churning food in the stomach, and segmentation.
19
Q
Where do Mechanical and Chemical Digestion occur?
A
Occurs in the mouth, stomach, and small intestine.
20
Q
What is Chemical Digestion?
A
The breakdown of food material to molecules.
21
Q
With absorption of nutrients, electrolytes, water, and fats, where are these being put into?
A
Nutrients, electrolytes, and water are transported into veins.
Fats are transported into lymphatics.
22
Q
What is Defecation?
A
Elimination of indigestible substances.
23
Q
T/F: As food passes through the GI tract, the body takes every thing possible.
A
False! As food passes through the GI tract, the body takes what it needs.
24
Q
What type of muscle does the intestine contain?
A
Circular and longitudinal smooth muscle.
25
How does the intestinal circular and longitudinal smooth muscle aid with Peristalsis?
Peristalsis utilizes coordination of these muscles to propel food through the lumen.
26
How does the intestinal circular and longitudinal smooth muscle aid with Segmentation?
Segmentation utilizes these muscles to mix rather than propel.
27
Name the organization for the entire length of the GI tract beginning at the lumen.
1) Mucosa
2) Submucosa
3) Muscularis externa
4) Serosa (mesothelium) or adventitia
28
What 3 things is the Mucosa comprised of?
True epithelium + lamina propria + muscularis mucosae
Epithelium is either stratified squamous or simple columnar.
29
Generally speaking, what does the Submucosa contain?
Arteries, veins, nerves, lymphatics, and sometimes mucus glands.
30
What is the Muscularis Externa?
Smooth muscle with an inner circular layer + an outer longitudinal layer
31
What innervates the Muscularis Mucosa?
Submucosal Nerve Plexus
32
What innervates the Muscularis Externa?
Myenteric Nerve Plexus
33
What does the Submucosal Nerve Plexus do?
Signals:
1) submucosal glands to secrete
2) muscularis mucosae to contract
34
Where is the Myenteric Plexus located?
Located between the circular and longitudinal layers of muscularis externa.
35
What does the Myenteric Plexus control?
Controls peristalsis and segmentation
36
Name the 4 types of mucus membranes?
1) Protective
2) Secretory
3) Absorptive (Nutrients)
4) Absorptive (Water & Electrolytes)
37
What type of epithelium makes up a PROTECTIVE mucus membrane?
Stratified squamous epithelium
38
Where is a protective mucus membrane found?
Oral cavity, pharynx, esophagus, and anus
39
What type of epithelium makes up a SECRETORY mucus membrane? What does it do?
Simple columnar epithelium
Specialized for secreting mucus
40
Where is a secretory mucus membrane found?
Found only in the stomach as mucus-secreting cells and mucus-neck cells.
41
What type of epithelium makes up a ABSORPTIVE (Nutrients) mucus membrane? What makes them special for absorbing nutrients?
Simple columnar cells
They are modified with increased surface area for absorbing nutrients.
42
Where is an absorptive (nutrients) mucus membrane found?
Found in the small intestine
43
What type of epithelium makes up a ABSORPTIVE (water & electrolytes) mucus membrane? What does the epithelium switch to in the anus?
Simple columnar
Switches to stratified squamous in the anus
44
Where is an absorptive (water & electrolytes) mucus membrane found?
Found in large intestine
45
What is the Alveolar Ridge?
The line between the tooth and gum.
46
In the oral cavity, what is the Vestibule?
The space between the lip and the alveolar ridge.
47
What is a Frenulum?
A fold
48
What is the Labial Frenulum?
This is a fold from the lip to the gum, also called the Frenulum of the Lip.
49
What is the Lingual Frenulum?
A fold from the tongue to the floor of the oral cavity.
50
Where do salivary glands open into the oral cavity?
Under the tongue and also through the cheek.
51
What forms the roof of the oral cavity?
Hard (maxillary and palatine bones) and soft palates.
52
What dangles down from the soft palate?
The uvula (little grape)
53
What forms the lips? What forms the cheeks?
Lips are formed from orbicularis oris.
Cheeks are formed by the buccinator muscle.
54
Name the lateral arches of the soft palate.
Palatoglassal arch (from palate to tongue) and Palatopharyngeal arch (from palate to pharynx).
55
What is the tongue covered in? Are these taste buds?
Papillae, which are not taste buds
56
Name the 3 lingual papillae covering the tongue. Which contain taste-buds?
Filiform, Fungiform, and Circumvallate.
Fungiform and Circumvallate contain taste-buds.
57
Describe Filiform papilla.
They resemble pointed cones.
They have no tastebuds.
Most numerous.
58
Describe Fungiform papilla.
Fungiform papillae resemble mushrooms.
Possesses tastebuds.
59
Describe Circumvallate papilla.
A papilla resembling a circular wall.
Possesses tastebuds.
60
What is Sulcus Terminalis?
A terminal groove that separates the circumvallate papilla and lingual tonsil.
61
What are Fauces?
The opening between the oral cavity and the oropharynx.
62
What are the 3 borders of the Fauces?
Palatoglossal arch, uvula, and sulcus terminalis.
63
What is the Tonsilar Ring? What is it comprised of?
A ring of protective tonsils in the oropharynx.
Tonsilar Ring = Palatine + Lingual Tonsils
64
What is the main function of Salivary Glands?
They produce and deposit saliva into the oral cavity.
65
What does the Parotid Gland contain and do?
Contains serous cells that secrete amylase and lysozymes into the parotid duct.
Amylase digests carbohydrates. Lysozymes lyse bacteria.
66
Where does the Parotid Duct pass through to get to the oral cavity?
Passes through the buccinator muscle.
67
What does the Sublingual Gland contain and do?
Contains mucous cells that secrete mucus for lubrication (via sublingual duct).
68
What does the Submandibular Gland contain and do?
Contains serous and mucous cells to secrete mucus, amylase, and lysozymes (via submandibular duct).
69
How many teeth are there in total?
There are 32 teeth in total.
70
How many teeth are:
-Incisors
-Cuspid/Canina
-Bicuspid/Premolar
-Molars
2 incisors
1 Cuspid/Canine (for shearing and tearing)
2 Bicuspid/Premolars
3 Molars
71
What is the function of the Esophagus?
Carries food material (bolus) from the oral cavity to the stomach.
72
What type of epithelium makes up the Esophagus?
Stratified squamous epithelium
73
How does the Muscularis externa transition muscle types from within the esophagus?
Transitions from skeletal (voluntary) to smooth (involuntary).
74
Why are there large folds in the Esophagus?
Due to thick Muscularis externa. The lumen is collapsed except when food passes through.
75
What type of glands are found in the submucosa of the Esophagus? What is the function of these glands?
Mucus glands, which secrete mucus for lubrication as the bolus of food passes the glands.
76
T/F: The external layer of the Esophagus is serosa.
False! The external layer is adventitia, not serosa.
77
Where does the Inferior Vena Cava pass through the respiratory diaphragm at?
The Caval foramen at the level of Thoracic vertebra 8 (T8).
78
Where does the Esophagus pass through the diaphragm?
Passes through the Esophageal Hiatus at the level of Thoracic vertebra 10 (T10).
79
What is the Cardiac Sphincter?
Muscle fibers of the respiratory diaphragm that serve as functional sphincter muscles of the esophagus.
80
What layer of the muscularis externa serves as the sphincter muscle of the esophagus?
The inner circular layer of the muscularis externa functions as the sphincter muscle of the esophagus.
81
What is the Lower Esophageal Sphincter?
The inner circular layer of muscularis externa, which functions as the sphincter muscle of the esophagus.
82
Where does the Aorta pass the Respiratory Diaphragm at?
At the level of Thoracic vertebra T12.
83
T/F: The stomach is a site for chemical and mechanical digestion.
True!
84
In the stomach, what is the Pyloris?
A pyloric sphincter that prevents the food from leaving the stomach.
85
In the stomach, what are Rugae?
Folds formed when the stomach decreases in size (looks like an accordion).
86
Name the 3 layers of smooth muscle that make up the muscularis externa of the stomach.
Innermost oblique, middle circular, and outer longitudinal.
87
In the stomach, what is the pyloric sphincter muscle formed from?
Formed from a thickened middle circular layer.
88
What do Mucus Neck Cells do? Why is this function important?
Secrete mucus that lines the neck of the gastric pit. The mucus protects the stomach from digesting itself.
89
What types of glands do the Fundus and Body of the stomach contain?
Gastric glands
90
What is the function of Parietal Cells?
Excrete HCl, which makes the stomach pH = 2 for the hydrolysis of proteins
91
What is the function of Chief Cells?
Excrete Pepsinogen. In combination with HCl, we get Pepsin which breaks down proteins.
92
What is the function of Enteroendocrine cells?
Secretes the hormone Gastrin
93
When is Gastrin produced?
When food enters the stomach
94
What does Gastrin do?
Stimulates Parietal cells to excrete HCl and Chief cells to excrete Pepsinogen.
95
"Chemicals travel through a duct to a lumen"
Exocrine or Endocrine?
Exocrine
96
"Hormones travel in the blood to other cells"
Exocrine or Endocrine?
Endocrine
97
The stomach contains both exocrine and endocrine cells. What does each of these produce?
Exocrine cells excrete HCl and Pepsinogen. Endocrine cells secrete hormones (Insulin and Glucagon).
98
What hormones do the Endocrine cells in the stomach secrete?
Gastrin
99
What is the main function of the Small Intestine?
It is the site for absorption of nutrients including Glucose, Vitamins, and Fats.
100
Name the 3 parts of the Small Intestine.
Duodenum, Jejunum, and Ileum
101
Where does the Duodenum begin?
After the Pyloric Sphincter
102
Where does the Ileum end?
At the Ileo-cecal valve
103
The Small Intestine is specialized for absorbing nutrients. What type of epithelial cells would be good for this?
Simple columnar cells
104
What are Plica cicularis? Why are they good?
Circular folds in the Small Intestine. Increase surface area for absorption.
105
What are Villi and why are they good for the Small Intestine?
Macroscopic finger-like projections of the mucosa, which help to increase surface area for absorption.
106
What are Microvilli and why are they good for the Small Intestine?
Microscopic folds on apical surface of cells, which help to increase surface area for absorption.
107
What are located between adjacent villi?
Crypts of Lieberkuehn
108
What is the function of Paneth cells? Where are they located?
Secrete Lysozymes to lyse and destroy bacteria. They are located at the base of crypts.
109
Where are 2 places that we can find Lysozymes in the digestive system?
Small Intestine and in the Serous fluid of the Parotid and Submandibular glands.
110
What are Peyer's Patches?
Aggregated lymphoid nodules in the Small Intestine
111
What are Lacteal Vessels and what is their function?
Specialized ducts of the Lymphatic System to carry fats.
112
What transfers emulsified fats into Lacteal Ducts?
Absorptive cells
113
What is the function of Goblet cells?
To secrete mucus
114
What are Brunner's glands?
Mucus-secreting cells in the submucosa.
115
Where are the 2 places we find submucosal mucus cells?
Only in the Esophagus and Duodenum.
116
In regard to Enteroendocrine cells, what does food entering the Duodenum stimulate?
Stimulates the secretion of the hormones Cholecystokinin (CCK) and Secretin
117
What does CCK do?
Signals the gallbladder to contract and release bile into the Duodenum
118
What does Secretin do?
Stimulates the Pancreas to excrete digestive juices into the Duodenum.
119
What is the main function of the Large Intestine?
Absorption of water and electrolytes (sodium, potassium, acids, vitamins, and bases).
120
What structures does the Large Intestine contain?
Cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum
121
Where does the Large Intestine begin?
Begins at the ileo-cecal junction (the junction of the ileum and cecum).
122
What is the Ileo-cecal valve? How is it formed?
It is a valve between the ileum of the small intestine and the cecum of the large intestine. All sphincter muscles are formed from the circular layer of the muscularis externa.
123
Where does the ascending colon become the transverse colon at?
At the right colic or hepatic flexure (by the liver).
124
Where does the transverse colon become the descending colon at?
At the left colic splenic flexure (at the spleen).
125
What is the Vermiform Appendix?
A worm-shaped extension of the cecum.
126
What is Taenia Coli?
3 bands of longitudinal smooth muscle of the muscularis externa along the Large Intestine.
127
What are Haustra?
Pockets formed by the contraction of the three taenia coli in the Large Intestine
128
What are Epiploic Appendages?
Fat-filled pounches hanging from the large colon.
129
What types of epithelial cells are present within the Large Intestine to aid with absorption of water and electrolytes? What is absent?
Simple columnar cells
However, there is an absence of Villi as there is no need for enormous surface area to absorb water and minerals.
130
T/F: There are no Crypts of Lieberkuehn in the Large Intestine.
False! There are very deep Crypts of Lieberkuehn in the Large Intestine. They are larger than those in the Small Intestine.
131
T/F: There are no Goblet cells within the Large Intestine.
False! There is a very abundant source of Goblet cells within the Large Intestine. More than there are in the Small Intestine.
132
Why is there a great abundance of Goblet cells within the Large Intestine?
The Large Intestine is specialized for absorbing water & electrolytes. This then requires a great deal of mucus to lubricate the dessicated (dry) feces.
133
Name one species of bacteria found in the colon.
Escherichia coli (E. coli)
133
T/F: There are no lymphoid nodules present within the Large Intestine.
False! There are abundant aggregated lymphoid nodules in the submucosa of the Large Intestine. They are not macroscopic, thus, they are not called Peyer's Patches.
134
In the Large Intestine, the muscularis externa has 2 layers of smooth muscle. What are they?
Inner circular and outer longitudinal
135
What is considered the "longitudinal" muscle in the Large Intestine?
"Ribbons of the colon" or taenia coli Rectum
136
What does the Rectum eventually become?
The anus or anal canal
137
How does epithelium change from the Rectum to the Anus/Anal Canal?
Simple columnar epithelium becomes stratified squamous epithelium
138
What shape does the Lumen of the Colon appear as? Why?
Triangular, due to the 3 tenia coli
139
Why are there more abundant aggregated lymphoid tissues within the Large Intestine as compared to the Small Intestine?
More than Small Intestine because of the presence of multitudes of bacteria which live there.
140
What is the distal portion of the Colon?
The Rectum
141
What does the Rectum terminate as?
The Anus or Anal Canal
142
What does the Anal Valve do?
Regulates movement of feces from rectum to anal canal.
143
Where is the Anal Valve located?
Between the Rectum and Anus or Anal Canal
144
What is the transition of epithelium in the Anal Canal?
From simple columnar to stratified squamous epithelium
145
What does the Anal Valve contain/consist of?
Anal columns and Anal sinuses (which are spaces between the columns).
146
What is the Internal Sphincter Muscle in the Rectum?
Inner circular layer of muscularis externa, which is smooth muscle under involuntary control by the Autonomic Nervous System.
147
What muscle serves as the External Anal Sphincter Muscle?
Muscle fibers of the Levator ani muscle, which is skeletal muscle under voluntary control by somatic motor fibers of the Pudendal nerve.
148
Which rectal sphincter muscle is under involuntary control?
Internal Sphincter Muscle
149
Which rectal sphincter muscle is under voluntary control?
External Sphincter Muscle
150
Bile is produced in __________ and stored in _______ ____________.
Liver, Gall Bladder
151
What is the function of Bile?
Bile is used in the Duodenum to breakdown fats.
152
When fats enter the Duodenum, what do Enteroendocrine cells do?
They secrete the hormone Cholecystokinin (CCK), which causes the contraction of gallbladder to move Bile into the Duodenum.
153
What is the function of the Biliary Tree?
Carries bile from the Liver to the Gallbladder, and from the Gallbladder to the Duodenum.
154
T/F: There is a direct connection from the Liver to the Gallbladder.
False! There is NO direct connection between the Liver and the Gallbladder.
155
T/F: The Liver only excretes bile when necessary.
False! The Liver constantly excretes bile, which flows to the Duodenum.
156
The Liver is constantly excreting bile. If there is not a bolus of food in the Duodenum, what happens?
Sphincter muscles at the end of the Common Bile Duct are closed. As a result, bile is forced to flow into the Cystic Duct and into the Gallbladder.
157
What is the Duodenal Papilla?
The opening of the Duodenal Ampulla into the lumen of the Duodenum.
158
What is the Duodenal Ampulla?
Where the Common Bile Duct and Pancreatic Duct meet at the Duodenum.
159
A bolus of food material entering the Duodenum stimulates the secretion of 2 different hormones from enteroendocrine cells of the Duodenum. Name them.
Cholecystokinin (CCK) and Secretin
160
What does CCK do?
Causes the Gallbladder to contract, excreting bile into the Duodenum.
161
What does Secretin do?
Causes the exocrine cells in the pancreas to excrete hormones and sodium bicarbonate into the Duodenum.
162
Bile travels from the Liver through the right and left _______________ ________, which join to form a ______________ _____________ ___________.
Hepatic Ducts, Common Hepatic Duct
163
The Cystic Duct joints the Common Hepatic Duct to form the ______________ _________ _________.
Common Bile Duct
164
The Pancreatic Duct joints the Common Bile Duct to form the _____________ or ________________ _____________.
Duodenal or Hepatopancreatic Ampulla
165
What does the Pancreatic Duct do?
Carries enzymes of digestion from the Pancreas to the Duodenum.
166
Hepatopancreatic describes the duct as being from the _________ and the _______________.
Liver, Pancreas
167
What is an Ampulla?
A structure that is "swelling".
168
It can be seen that the merger of the ___________ ____________ and ______________ _________ forms a "swelling" or Ampulla.
Common Bile and Pancreatic Ducts
169
What does the Head and the Tail of the Pancreas come into contact with?
Head with Duodenum.
Tail with Spleen.
170
T/F: The Pancreas contains only Exocrine cells.
False! The Pancreas contains both Exocrine and Endocrine cells.
171
What are Exocrine cells in the pancreas?
Acinar cells which excrete enzymes into a duct and respond to Secretin secreted from the enteroendocrine cells of the Duodenum.
172
In the Pancreas, what are 5 enzymes that the Exocrine cells excrete?
Proteases, Amylases, Lipases, Nucleases, and Bicarbonate.
173
What do Proteases do?
Breakdown polypeptides to amino acids.
174
What do Amylases/Carbohydrases?
Breakdown complex sugars (Carbohydrates) into simple sugars (i.e. Glucose).
175
What do Lipases do?
Breakdown lipids into fatty-acids.
176
T/F: Lipases emulsify fats to lipids.
False! Bile emulsifies fats to lipids.
177
What do Nucleases do?
Breakdown of the nucleus into nuclear material (DNA, RNA).
178
What is Bicarbonate?
A buffer to neutralize the acidic chyme or bolus from the stomach.
179
What do Endocrine cells do?
Secrete a hormone into the circulatory system.
180
What hormones are secreted in response to blood Glucose concentrations?
Insulin and Glucagon
181
What do Alpha Cells in the Pancreas do? What does this cause?
Secrete Glucagon to transport Glucose from the Liver into the blood.
This causes the concentration of Glucose in the blood to increase.
182
What do Beta Cells in the Pancreas do? What does this cause?
Secrete Insulin to transport Glucose from blood into the cells of the body and into the Liver.
This causes the concentration of Glucose in the blood to decrease.
183
What are Islands of Langerhans?
Alpha and Beta cells, which collectively secrete hormones into veins.
184
The Pancreas produces enzymes and Bicarbonate. Where are these released into?
Released into the Pancreatic Duct and into the Duodenum.
185
The Pancreas produces the hormones Insulin and Glucagon. Where are these released into?
Released into the Circulatory System
186
The Liver is composed of 4 lobes. Name them.
Right lobe, Left lobe, Caudate ("tail of the liver") lobe, and Quadrate ("4-sided") lobe.
187
What are the cells of the Liver called?
Hepatocytes
188
What are the 7 major functions of the Hepatocytes?
CANVSST (almost like Canvas but with a T)
-Convert the Bilirubin to Bile
-Assist the Spleen in removing dead and dying RBCs
-Nutrient metabolism and storage
-Vitamin storage
-Synthesis and excretion of bile
-Synthesize plasma proteins
-Toxin removal also called detoxification
189
To perform their functions, Hepatocytes require what 3 things?
Oxygen from an arterial supply.
Contact with the nutrients from digestions.
Ducts to carry away the bile.
190
What carries oxygen to the Liver?
Hepatic arteries and arterioles carry oxygen to the Liver.
191
What carries nutrients of digestion to the Liver?
The Hepatic Portal Vein carries nutrients of digestion to the Liver.
192
What carries bile away from the Liver?
Hepatic Ducts carry bile away from the Liver.
193
There is an ____________ supply INTO the Liver, and _____________ flow INTO and OUT of the Liver.
arterial, venous
194
What makes up the Portal Triad?
Hepatic artery, Hepatic Portal vein, and Hepatic duct.
195
What does the Hepatic Portal Vein do?
Carries nutrients INTO the Liver.
196
What does the Hepatic Vein do?
Carries nutrients and CO2 OUT of the Liver and into the Inferior Vena Cava (IVC).
197
What is the Porta Hepatis?
Entrance of the Portal Triad into the Liver ("the door to the Liver").
198
Hepatocytes are organized into _____________.
Lobules ("little lobes")
199
What is a Lobule?
A hexagonal shape around a Central Vein.
200
Where are Portal Triads found?
Found in every corner of the Hexagonal Lobule
201
T/F: Each lobe of the liver has one Sinusoidal Capillaries.
False! Each lobe of the liver has many Sinusoidal Capillaries.
202
Blood flows from the Hepatic artery and Hepatic Portal vein into the lobule and into a ______________ _______________.
Sinusoidal Capillary
203
What is the blood in the Sinusoidal Capillary in contact with? Why?
In contact with Hepatocytes, so they can perform their many functions.
204
Blood in Sinusoidal Capillaries flows past Hepatocytes and into the _______________ __________.
Central Vein
205
What is located in the center of each lobule of the liver?
Central Vein
206
What do all of the Central Veins join to form?
Hepatic Veins
207
Where do the Hepatic Veins drain into?
Inferior Vena Cava
208
What does a Bile Canaliculus do?
Carries bile away from the Hepatocytes.
209
Many Canaliculi join together to form what?
the Hepatic Duct
210
What does the Hepatic Duct do?
Carries bile towards the Gall Bladder
211
What are Kupffer Cells?
Macrophages in the Sinusoidal Capillaries
212
What is the Peritoneum?
A serous membrane (mesothelium) that lines the Abdominal organs.
213
What is the Visceral Peritoneum?
The part of the serous membrane in contact with the organs of digestion. One continuous membrane.
214
What is the Parietal Peritoneum?
The part of the serous membrane in contact with the Abdominal wall.
215
What does the term "Mesentery" mean?
A double layer of Visceral Peritoneum.
216
If an organ has a Mesentery, what is it called?
An Intraperitoneal organ
217
What is an organ without a Mesentery called?
A Retroperitoneal organ
218
Is the liver an intraperitoneal or retroperitoneal organ?
The Liver is an intraperitoneal organ. It actually has 2 Mesenteries, both the Falciform ligament & the Lesser Omentum.
219
How many Mesenteries does the Liver have?
2, both the Falciform Ligament & the Lesser Omentum
220
What is the MAIN function of the Urinary System?
To maintain Homeostasis
221
What 5 things does the Urinary System do to help maintain Homeostasis?
1) Storage and excretion of urine
2) Filtration of blood
3) Releases hormones
4) Regulation of erythrocyte production
5) Regulation of ions and acid/base levels
222
What is Urine?
Filtrate that is removed from the blood that the body does not need in excess in order to survive.
223
What happens if we have buildup of substances in the blood?
Too much of something can be bad, because if it takes us out of homeostasis, it becomes toxic!
224
What is the MAIN function of the kidney?
Filters waste from the blood to maintain homeostasis and converts the filtrate into urine
225
In patients with chronic kidney disease, what is the kidney unable to do?
Unable to filter substances, thus, it cannot maintain homeostasis.
226
If the kidney is unable to maintain homeostasis and filter substances, what will happen short-term and long-term?
The accumulation of uremic toxins in the kidney will decrease Erythropoietin production. This then decreases RBC production (Erythropoiesis) in the bone marrow, leading to anemia and later heart failure.
227
In relation to chronic kidney disease, what is anemia?
Anemia is a symptom of chronic kidney disease.
228
Urogenital system derives from embryonic tissue called what?
Intermediate Mesoderm
229
What is the Intermediate Mesoderm?
Groups of cylindrical cells running down the posterior abdominal wall.
230
What does the Condensed Intermediate Mesoderm form?
Forms the urogenital ridge, which projects into the embryonic abdominal cavity.
231
What type of organs make up the urogenital ridge?
Urinary + Internal Reproductive Organs
232
What structures develop from the urogenital ridge?
Pronephros and Pronephric Duct
233
What is the function of Pronephros?
Their only function is DEGENERATION, which will instigate the formation of Mesonephros (the 2nd set of embryonic excretory organs).
234
How do Mesonephric nephrons appear to develop?
Mesonephric nephrons develop as sac-like segments that function in urine production.
235
What does the Pronephric Duct turn into and what does it do?
The Pronephric Duct is retained as the Mesonephric Duct and will drain waste/urine from the Mesonephric Nephrons to the Cloaca.
236
What is the Cloaca?
The common collection area for waste.
237
How long do Mesonephros persist?
Persist until week 10
238
What do Mesonephros give rise to?
Degenerating Mesonephros trigger the development of Metanephros.
239
From which structures do the Metanephros develop?
Metanephros develop simultaneously from Ureteric Buds and Metanephric Blastema.
240
Where do Uretic Buds come from?
Directly from Mesonephric Duct
241
Where do Metanephric Blastema come from and what are they?
They are a cluster of cells produced from the intermediate mesoderm.
242
What do Uretic Buds develop into?
Develop into the structures that COLLECT urine.
243
What are the structures that are collecting urine?
Ureter, Renal Calyces, Renal Pelvis, and Collecting Ducts.
244
What do Metanephric Blastema develop into?
Develop into the structures that PRODUCE urine.
245
What are the structures that are producing urine?
Glomerular capsule, Proximal convoluted tubule, Nephron loop, and the Distal convoluted tubule.
246
How does the structure of the kidney form from the uretic bud and metanephric blastema?
The Uretic Bud will come off of the Mesonephric Duct and also trigger the Metanephric Blastema for differentiation. The Uretic Bud will then grow into and form a complex with the Metanephric Blastema, which will form the Kidney.
247
The Kidney is formed when what 2 structures form a fully-functioning complex?
Uretic Bud + Metanephric Blastema
248
What happens at Week 7 of Urinary Development?
The Urorectal Septum divides the Cloaca into the Urogenital Sinus and the Anorectal Sinus. This helps to separate the bladder from the rectum.
248
Which develops first: Uretic Bud or Metanephric Blastema? Why?
Uretic Bud develops first, because we need a place to store/collect urine before we produce it.
249
What does the Urogenital Sinus develop into?
Develops into the future urinary bladder and urethra.
250
What is the pathway of Kidney migration?
During weeks 6-9, the developing Kidneys migrate to a more superior position in the abdominal cavity. As they ascend, they obtain temporary blood vessels from nearby vasculature to keep supplying the Kidney. By week 9, the Kidneys migrate to the lumbar region and receive permanent renal arteries from the abdominal aorta.
251
What is meant by the Indifferent Duct System?
All embryos begins with both the Mesonephric Duct and the Paramesonephric Duct before only 1 is retained based on genetics.
252
What determines which duct system is retained in embryos?
Genetics, specially the sex genes
253
What does retention of the Mesonephric Duct create?
Penis and associated structures (XY)
254
What does retention of the Paramesonephric Duct create?
Uterus and associated structures (XX)
255
The degeneration of which temporary set of embryonic excretory organs triggers the production of the mesonephros?
Pronephros
256
What are the Ureters, Urinary Bladder, Urethra collectively referred to as?
Collectively referred to as the urinary tract
257
What is the function of the Urinary Tract?
Transports the urine out of the body.
258
What are the organs of the Urinary System?
Paired Kidneys and the Urinary Tract (Ureters, Urinary Bladder, Urethra).
259
Where does the superior and inferior border of the Kidney sit?
Superior border sits just below T12.
Inferior border sits at about L3.
260
T/F: The Kidney is retroperitoneal.
True!
261
Where does the Suprarenal or Adrenal Gland sit?
Sits atop each Kidney
262
What color is the Kidney?
Reddish Brown
263
The Right Kidney sits slightly more inferior than the Left Kidney. Why?
The Liver is pushing down on the Right Kidney.
264
The Kidney is surrounded by 2 layers of fat. What is the function of this?
The fat serves to protect and cushion the Kidney from trauma.
265
What are 3 functions of the Renal Capsule of the Kidney?
Maintains the shape of the Kidney, protects the Kidney from damage, and prevents infection from spreading (into and out of the kidney).
266
What type of tissue is the Renal Capsule of the Kidney?
Dense, irregular connective tissue
267
The Renal Capsule of the Kidney has a concave medial border. What is this called and what happens here?
The concave medial border is called the Hilum. This is where blood vessels enter & exit the kidney. The Ureter also exists the kidney here.
268
The Kidney is divided into 3 parts. Name them.
Cortex (outer), medulla (inner), and Renal Pelvis
269
What does the Cortex of the Kidney do?
Projects into the medulla as renal columns to divide it into Renal/Medullary Pyramids.
270
What do the Renal/Medullary Pyramids do?
Increases the surface area of the Medulla, where urine is produced, allowing for more functional capacity.
271
Where is urine produced?
In the Renal/Medullary Pyramids via the nephrons.
272
From the Renal/Medullary Pyramids, where does the urine travel to get to the urinary bladder?
Drips into the Renal Papilla, then minor calyx, major calyx, renal pelvis, ureter, and then urinary bladder.
273
Describe the direction of movement from urine production in the Renal Pyramids to ending up collecting in the Urinary Bladder.
Renal Pyramids --> Renal Papilla --> Minor Calyx --> Major Calyx --> Renal Pelvis --> Ureter --> Urinary Bladder
274
What branches off of the abdominal aorta to deliver blood to the kidneys?
Renal Arteries
275
What do Renal Veins do?
Bring deoxygenated blood back to the Inferior Vena Cava
276
Where do Renal Veins lie in comparison to Renal Arteries?
The Renal Veins are anterior to the arteries.
277
T/F: The Renal Veins are symmetrical.
False! The Renal Veins are asymmetrical due to the location of the IVC on the right side of the body.
278
T/F: Anytime there is asymmetry in the body, we need to specify Left versus Right-sided structures.
True!
279
T/F: The Right Gonadal Vein drains into the Right Renal Vein.
False! The Left Gonadal Vein drains into the Left Renal Vein. The Right Gonadal Vein drains into the right IVC instead.
280
Which Renal Vein is longer? Why?
The Left Renal Vein is longer, because it has to cross over the Abdominal Aorta to get to the Right Kidney.
281
What does the Left Renal Vein collect blood from?
From the kidney as well as the Left Gonadal Vein
282
Between what 2 structures is the Renal Vein located?
The Renal Vein is located between the Superior Mesenteric Artery and the Abdominal Aorta.
283
What is Nutcracker Syndrome?
This is when the Renal Vein becomes entrapped, causing compression, which leads to a lack of blood drainage from the Gonads. This causes Veriocele and toxic pooling of blood.
284
How many Segmental Arteries branch from the Renal Artery?
5 Segmental Arteries branch from the Renal Artery.
285
Describe the order of blood supply to the kidney beginning with the Renal Artery and ending with the Cortical Arteries.
Renal Artery --> Segmental Arteries --> Interlobar Arteries --> Arcuate Arteries --> Cortical Arteries
286
Where are Interlobar Arteries located?
Between Renal/Medullary Pyramids
287
Where are Arcuate Arteries located?
Across the tops of the Renal/Medullary Pyramids.
288
Where are Cortical Arteries located and what do they give off?
These penetrate the Cortex and give off Afferent Arterioles.
289
What are Afferent Arterioles in the Urinary System?
The smallest branches, which create capillary balls called Glomeruli.
290
What is the function of Glomeruli?
This is where filtrate is removed from the blood.
291
What types of arteries exit the glomerulus?
Efferent Arterioles exit the Glomerulus.
292
What is the Nephron?
This is the functional unit of the Kidney, in which all filtration of blood takes place here.
293
What are the 5 parts of the Nephron?
Corpuscle, Proximal Convoluted Tubule, Nephron Loop of Henle, Distal Convoluted Tubule, and Collecting Ducts.
294
What do Nephrons do?
Modifies filtrate to form urine from three processes: filtration, reabsorption, and secretion.
295
What 3 processes modify filtrate to form urine?
Filtration, Reabsorption, and Secretion.
296
What is Filtration?
Movement of substances from blood to the capsular space.
297
What is Reabsorption?
Movement of substances from tubular fluid back to the blood.
298
What is Secretion?
Movement of substances from the blood to the tubular fluid.
299
What is the Renal Corpuscle made up of?
Made of the glomerulus and the glomerular capsule.
300
The Renal Corpuscle has 2 poles, what are they?
The Vascular Pole where afferent arterioles enter. Then, the Tubular Pole where filtrate enters the tubular system.
301
What is the Glomerulus?
A tangle of capillaries that extend from the afferent arteriole.
302
What surrounds the Glomerulus?
The Glomerular Capsule surrounds the Glomerulus.
303
The Glomerular Capsule is made of 2 layers, what are they?
The Parietal Layer and the Visceral Layer.
304
In the Glomerular Capsule, what type of epithelium is the Parietal Layer?
Simple squamous epithelium
305
In the Glomerular Capsule, describe the Visceral Layer.
The Visceral Layer is adhered to the Glomerulus and is made of Podocytes.
306
What are Podocytes?
Specialized cells that help to filter or reject the filtering of certain substances.
307
Where is the Capsular Space located? What happens here?
Lies between the Parietal and Visceral Layer.
This is where filtrate is collected.
308
How does filtration occur?
Filtration occurs because of increased pressure in the Glomerulus. This forces blood out of the blood vessels.
309
What 2 things is the Filtration Membrane made of?
Fenestrated Endothelium of the Glomerulus and the Visceral Layer of the Glomerular Capsule, made of Podocytes with filtration slits.
310
What is the function of the Filtration Membrane?
It allows substances that are small enough to flow through as filtrate while also preventing other substances, such as proteins and cells, from entering the filtrate.
311
What does the filtration membrane allow to exit the Glomerulus?
Only allows the smallest solutes to exit the Glomerulus
312
What causes solutes to be pressed out of the blood?
Solutes are pressed out of the blood due to high pressure in the Glomerulus.
313
T/F: Filtration is a selective process.
False! Basically, anything that is small enough to get pushed through the filtration membrane will go.
314
Describe the structure of the Proximal Convoluted Tubule.
Simple cuboidal epithelium with microvilli to help increase reabsorption capacity.
315
What is the function of the Proximal Convoluted Tubule?
Actively reabsorbs and secretes substances to modify the filtrate.
316
What is the Nephron Loop of Henle made up of?
It is made up of 2 limbs, one that loops down in the medulla and one that loops back up into the cortex.
317
What is function of the Nephron Loop of Henle?
Primary function is reabsorption of water back to the blood.
318
There are 2 types of Nephrons, what are they?
Cortical Nephrons, which work under normal conditions.
Juxtamedullary Nephrons, which work during periods of high activity and produce concentrated urine.
319
Describe the structure of the Distal Convoluted Tubule.
Simple cuboidal epithelium with sparse microvilli.
320
What is the function of the Distal Convoluted Tubule?
Primary function is secretion and absorption.
321
Describe the histological differences between the Primary Convoluted Tubule and the Distal Convoluted Tubule.
DCT:
-Simple cuboidal epithelium
-Sparse microvilli
-Narrow lumen
PCT:
-Simple cuboidal epithelium
-Tall and many microvilli
-Lumen looks really fuzzy
322
Name the capillaries around the tubules and the nephron.
Peritubular Capillaries surround the proximal and distal convoluted tubules.
Vasa Recta surround the Nephron Loop.
323
What is the function of the Collecting Tubules and Ducts?
To increase the absorption of water back to the blood.
324
What are the Collecting Tubules and Ducts under the influence of? What does this cause?
Act under the influence of Anti-Diuretic Hormone (ADH) and Aldosterone to limit the loss of water and sodium ions from the blood.
325
Where is the last place that filtrate can be modified?
Collecting ducts
326
Where does urine exit the Kidney through?
Through the Ureter
327
What are Ureters?
Fibromuscular tubes that carry urine into the pelvic cavity to empty into the urinary bladder.
328
Where do the Ureters insert into the bladder?
Insert in the posterolateral wall of the bladder.
329
What are the 3 layers of the Ureter?
1. Mucosa (transitional epithelium)
2. Muscularis (smooth muscle layers)
3. Adventitia (collagen and elastic fibers)
330
Why does the Ureter not have a submucosa layer?
The Ureters are too small for submucosa. They do not need the extra support offered by the submucosa.
331
Why is it a good thing for the Ureter mucosa to be transitional epithelium?
This allows stretching so that more fluid can flow.
332
Why does the Ureter enter the Bladder obliquely?
It increases the surface area of the ureter making contact with the bladder. It also creates a one-way valve which prevents urine from re-entering the ureter.
333
In relation to the Pubic Symphysis, how is the Bladder positioned? When the Bladder fills, how does this change?
Positioned posterior to and "tipped over" the Pubic Symphysis.
As the Bladder fills, it stands upright.
334
The Urinary Bladder is _____________________ and is thus covered by the Parietal Peritoneum.
Retroperitoneal
335
What are the 4 layers of the Urinary Bladder?
1. Mucosa (transitional epithelium)
2. Submucosa (dense, irregular connective tissue)
3. Muscularis (detrusor muscle)
4. Adventitia (outer loos connective tissue, with collagen and elastic fibers
336
Describe the structure of the submucosa in the Urinary Bladder.
It forms folds, called Rugae, which help to increase stretch in the Urinary Bladder.
337
What is the function of the Detrusor Muscle in the Urinary Bladder?
It contracts and helps to push all of the urine out of the Urinary Bladder.
338
In the Urinary Bladder, what is the Trigone? What does it allow for?
A triangular area formed by the entrance of the ureters and the formation of the internal urethral opening.
This allows space for urine to exit the bladder and enter the urethra.
339
What is Urethra made from?
Made from smooth muscle of the bladder.
340
Describe the Internal Urethral Sphincter.
It surrounds the Urethra opening and is made of smooth muscle, thus, it is under autonomic control.
341
Describe the distal end of the Urethra.
The distal end of the urethra is surrounded by skeletal muscle forming the external urethral sphincter. The external urethral sphincter is on the outside of the urethra and is under voluntary control.
342
In males, what are 2 additional things they have as part of the Urethra pathway out of the body?
Males are getting rid of both urine and semen out of the urethra.
Males also have a prostatic urethra that urine passes through before entering the penis.
343
What does Parasympathetic stimulation of the Bladder lead to?
This stimulates Micturition or urination.
Think P = PP
344
What does Sympathetic stimulation of the Bladder lead to?
This inhibits Micturition or urination.
Think S = Storage
Also, remember, you like barely have to pee when you're exercising.
345
How does the ANS control Micturition? Describe the steps.
1) Stretch receptors in the bladder trigger the Micturition Reflex Center.
2) Impulses travel to the Detrusor Muscle and the Internal Urethral Sphincter.
3) Smooth muscle in the Internal Urethral Sphincter relaxes.
4) Smooth muscle in the Detrusor contracts.
5) Person must consciously relax the External Urethral Sphincter.
346
Is the stomach an intraperitoneal or retroperitoneal organ?
The stomach is intraperitoneal with 2 mesenteries: both the greater and lesser omentum.
347
Are the Jejunum and Ileum intraperitoneal or retroperitoneal?
Intraperitoneal with the mesentery proper
348
Is the Transverse colon intraperitoneal or retroperitoneal?
Intraperitoneal with the tranverse mesocolon.
349
is the Sigmoid colon intraperitoneal or retroperitoneal?
Intraperitoneal with the sigmoid mesocolon
350
Name the Digestive Organs that are Intraperitoneal Organs.
Liver, stomach, jejunum, ileum, transverse colon, and sigmoid colon.
351
What is a Retroperitoneal Organ?
An organ located outside and behind the Parietal Peritoneum.
352
Name the Digestive Organs that are Retroperitoneal Organs.
RED PAD = Retroperitoneal
Rectum, Esophagus, Duodenum, Pancreas, Ascending colon, Descending colon.
353
T/F: Intraperitoneal Organs do NOT have a mesentery.
False! Intraperitoneal Organs have a mesentery, whereas retroperitoneal organs do not have a mesentery.
354
What are the 3 main arteries that the digestive organs receive oxygenated blood from?
Celiac Trunk, Superior Mesenteric artery, and Inferior Mesenteric artery.
355
What are the 1st, 2nd, and most inferior branches off of the Abdominal Aorta?
First branch = Celiac Trunk
Second branch = Superior Mesenteric artery
Most Inferior branch = Inferior Mesenteric artery
356
What does the Celiac Trunk supply?
Supplies all of the organs from the Esophagus through the Duodenum.
(Esophagus, Stomach, Spleen, Liver, Pancreas)
357
What does the Superior Mesenteric artery supply?
Supplies all of the organs from the Jejunum through the Transverse colon.
(Small intestine, Cecum, Vermiform Appendix, Ascending and Transverse colon)
358
What does the Inferior Mesenteric artery supply?
Supplies the Descending colon, Sigmoid colon, and Rectum.
359
The Celiac Trunk has 3 branches, name them.
Left Gastric artery, Common Hepatic artery, and Splenic artery.
360
Where does the Left Gastric artery go to?
To lesser curvature of the stomach
361
Where does the Common Hepatic artery go to? What does it split to form?
Goes to the Liver.
Splits to form Gastro-duodenal and Proper Hepatic.
362
Where does the Splenic artery go to? What artery does it give off?
Goes to the Spleen and Pancreas.
Gives off Left Gastro-omental artery.
363
Where do Gastro-Omental arteries follow?
Follow the greater curvature of the stomach.
364
Where do Gastric arteries follow?
Follow the lesser curvature of the stomach.
365
What does the Gastro-Duodenal artery supply?
Supply to the Right Gastro-Omental artery and the Duodenum.
366
What does the Proper Hepatic artery form? What else does it give off?
Splits to form Left and Right Hepatic arteries. Also, gives off the Right Gastric artery.
367
What do the Left and Right Hepatic arteries supply?
Supply to the left and right lobes of the liver.
368
What does the Embryology of the Gut-Tube explain?
Explains the Adult Morphology.
369
What structures does the Embryonic Foregut give rise to?
Stomach, Liver, Pancreas, Spleen, and Duodenum to Common Bile Duct.
370
What structures does the Embryonic Midgut give rise to?
Duodenum distal to common bile duct, remaining small intestine, cecum, ascending and transverse colon (to splenic fixture).
371
What structures does the embryonic hindgut give rise to?
Descending colon (at splenic fixture), sigmoid colon, and rectum.
372
What branch off of the abdominal aorta will eventually supply the Embryonic Foregut?
Celiac Trunk
373
What branch off of the abdominal aorta will eventually supply the Embryonic Midgut?
Superior Mesenteric artery
374
What branch off of the abdominal aorta will eventually supply the Embryonic Hindgut?
Inferior Mesenteric artery
375
What do veins going into the liver do?
Carry deoxygenated blood from organs of digestion and carry nutrients to the liver.
376
Where does venous blood from organs of digestion drain into?
Into the Hepatic Portal vein and then into the liver.
377
What are the 4 Organs of Digestion that get drained by the Hepatic Portal Vein?
Stomach, Spleen, Small Intestines, and Large Intestines.
378
What do Gastric veins drain?
Drain the stomach into the Hepatic Portal Vein.
379
What do Splenic veins do?
Drains the Spleen and Pancreas into the Hepatic Portal Vein.
380
What do Superior Mesenteric Veins drain?
Drains organs of the mid-gut (from the bile duct to splenic fixture).
381
What do Inferior Mesenteric Veins drain?
Drains organs of the hind-gut (from splenic fixture through the rectum).
382
What are the organs of the fore-gut drained by?
Drained by the Gastric and Splenic veins
383
What are organs of the mid-gut drained by?
Drained by the Superior Mesenteric vein
384
What are the organs of the hind-gut drained by?
Drained by the Inferior Mesenteric vein
385
What veins join to form the Hepatic Portal vein?
Gastric, Splenic, Superior Mesenteric, and Inferior Mesenteric.
386
What does the Superior Mesenteric Vein join to form the Hepatic Portal Vein?
The Superior Mesenteric joints the Splenic Vein to form the Hepatic Portal Vein.
387
What does Portal Venous Drainage mean?
These are the veins that drain into the Liver.
388
What organs have Portal Venous Drainage?
Spleen, Stomach, Pancreas, Small Intestines, and Large Intestines.
389
What does Caval Venous Drainage mean?
These are the veins that drain into the Inferior Vena Cava.
390
What organs have Caval Venous Drainage?
Kidneys, Gonads, and Liver.
391
What is the effect of parasympathetic stimulation on the rate of peristalsis?
Parasympathetic nerves INCREASE the rate of peristalsis.
392
What is the effect of sympathetic stimulation on the rate of peristalsis?
Sympathetic nerves DECREASE the rate of peristalsis.
393
What innervates the Muscularis Externa?
The Myenteric Nerve Plexus innervates the Muscularis Externa.
394
What innervates the Muscularis Mucosa?
The Submucosal Nerve Plexus innervates the Muscularis Mucosa.
395
What nerves innervate the GI tract?
There are 3 (Thoracic) Splanchnic nerves that innervate the GI tract.
396
How many arteries supply the GI tract?
There are 3 arteries that supply the GI tract.
397
What is the Sympathetic Innervation to the Embryonic Foregut?
Greater Splanchnic nerve
398
What is the Sympathetic Innervation to the Embryonic Midgut?
Lesser Splanchnic nerve
399
What is the Sympathetic Innervation to the Embryonic Hindgut?
Least Splanchnic nerve
400
In the GI tract, what accompanies arteries to their targets?
Sympathetic nerves accompany arteries to their targets.
401
How many parasympathetic nerves innervate the GI tract?
There are 2 parasympathetic nerves that innervate the GI tract.
402
Parasympathetic nerves travel ________ the GI tract to their targets.
atop
403
What is the parasympathetic innervation for the embryonic foregut and midgut?
Vagus Nerve (CN X)
404
What is the parasympathetic innervation for the embryonic hindgut?
Pelvic Splanchnic nerve (S2, 3, 4).
405
What are the similarities between Exocrine and Endocrine Glands?
Both are made of epithelial cells.
406
What is the difference between Exocrine and Endocrine Glands?
Exocrine glands secrete substances directly on the SURFACE (skin) of the body.
-Immediate reaction
-Sweat, electrolytes, etc.
Endocrine glands release substances directly into the BLOOD.
-Delayed reaction
-Completely inside the body
407
T/F: Exocrine glands are supplied by a bunch of blood vessels.
False! Endocrine glands must be supplied by a plethora of blood vessels.
408
What are 2 reasons for why endocrine glands are surrounded by a plethora of blood vessels?
1) To monitor the blood to look for areas with abnormal substance concentrations.
2) Hormone secretion as a response to abnormal concentrations. Hormones get right into the bloodstream.
409
Describe the structure of an Endocrine Gland.
Simple cuboidal cells (secretory cells) are clustered around fenestrated capillaries.
1) Cells release hormones into sinusoids (empty spaces)
2) Hormones flow through fenestrations into capillaries when they are needed.
410
Why is Pancreatic Cancer so deadly?
The Pancreas has a vast blood supply, which will quickly circulate cancerous cells to other parts of the body, particularly lymph nodes.
411
T/F: Hormones affect any type of cell they come into contact with.
False! Hormones ONLY affect cells that have a specific receptor (Target Cell).
412
T/F: The effect of a hormone is preprogrammed.
True!
413
What determines the specific reaction of a hormone?
The specific reaction is dependent on the target cell, not the hormone.
One hormone can cause different reactions in different target cells.
414
Name the 3 triggers that stimulate hormone secretion. Which is the most common?
Humoral, Neuronal Control, and Hormonal.
Hormonal is the MOST COMMON.
415
What is Humoral Hormone Secretion?
Hormone secretion is based on the concentration of a specific substance in the body, such as ions or nutrients.
416
What is Neuronal Control Hormone Secretion?
Nerve fibers stimulate the release of hormones. (Ex: Adrenal Gland).
417
What is Hormonal Hormone Secretion?
Other hormones stimulate the release of hormones.
418
How is hormone secretion regulated?
By FEEDBACK LOOPS.
419
What is a Positive Feedback Loop?
This is when an increase in a hormone leads to increase in a specific action.
420
What is a Negative Feedback Loop?
An increase in a hormone leads to a decrease in a specific action.
421
"An extension of the Hypothalamus"
What is this?
The Pituitary Gland
422
What is another name for the Pituitary Gland?
The Hypophysis
423
Describe the location of the Pituitary Gland.
It sits inferior to the brain in the hypophyseal fossa, which is a depression in the sella turcica of the sphenoid bone. The pituitary gland is suspended from the hypothalamus via a stalk or infundibulum.
424
What can the pituitary gland be divided into?
Anterior and posterior lobe
425
What controls/oversees the Pituitary Gland?
The Hypothalamus controls the Pituitary Gland. This is why it is important that they are connected.
426
The anterior lobe of the Pituitary Gland is under hormonal control via the _________________.
Hypothalamus
427
Describe how the anterior lobe of the Pituitary Gland produces hormones.
Hormones from the Hypothalamus enter the Hypophyseal-Hypothalamic Portal System (HHPS). These hormones will travel directly to the anterior lobe where they either stimulate or inhibit the production of hormones.
428
Where do Hormones secreted by the anterior lobe of the Pituitary Gland go?
They ultimately enter systemic circulation.
429
What does the Hypophyseal-Hypothalamic Portal System (HHPS) do?
It takes hormones that have been secreted into the blood from the Hypothalamus and shunts this blood towards the anterior lobe of the Pituitary Gland.
430
What is the anterior lobe of the Pituitary Gland made up of? What do these do?
Made of epithelial tissue that contains 5 different cells. These cells produce 7 different hormones.
431
What does Thyroid-Stimulating Hormone (TSH) do?
Stimulates the thyroid gland to release thyroid hormone, which will control/regulate metabolism.
432
What do Follicle-stimulating & Luteinizing Hormones do?
These act on the gonads to stimulate sperm and oocyte production and enable the release of sex hormones.
433
What does Adrenocorticotropic Hormone do?
Acts on the Adrenal Cortex to cause the release of corticosteroids.
434
What does Growth Hormone do?
Acts on all body tissues (especially muscles and bones) to stimulate growth of the body.
435
What does Melanocyte-Stimulating Hormone do?
Acts on melanocytes in the skin to produce melanin.
436
What does Prolactin do?
Acts on mammary glands of the breast for growth and milk production.
437
T/F: The posterior lobe of the Pituitary Gland produces its own hormones.
False! It does NOT produce any of its own hormones.
438
What does the posterior lobe of the Pituitary Gland do?
The posterior lobe stores and releases antidiuretic hormone and oxytocin produced in the Hypothalamus.
439
What do axons in the posterior lobe of the Pituitary Gland form?
The Hypothalamohypophyseal tract.
440
What is the posterior lobe of the Pituitary Gland made of?
Made of neural tissue
441
What does Antidiuretic Hormone do?
Stimulates the kidneys to reabsorb more water when dehydrated. This helps the body to retain water.
Also tells blood vessels to constrict when blood pressure is low to return it to normal (water loss -> low blood volume).
442
What does Oxytocin do?
-Stimulates ejection of milk from breast milk during breastfeeding.
-Induces contraction of smooth muscles in reproductive organs (e.g., uterine contractions during childbirth).
443
For the anterior and posterior lobes of the Pituitary Gland, how do they stain differently histologically?
Anterior lobe is made of epithelial cells which will take up H&E stain readily (stains darker).
Posterior lobe is made of unmyelinated axons and therefore resists most dyes (stains lighter).
444
What is Hypersecretion? What is the clinical name for this?
This is an overactive pituitary gland before puberty and before the growth plates have closed.
Because this is more growth hormone than usual, this is called Pituitary Gigantism.
445
What is Hyposecretion? What is the clinical name for this?
This is an underactive pituitary gland in which there is less growth hormone than usual. This is called Pituitary Dwarfism.
446
All endocrine control ultimately comes from what?
From the Hypothalamus
447
What are the 3 ways in which the Hypothalamus controls the endocrine system?
1) The Hypothalamus produces hormones that are transported and stored in the posterior Pituitary Gland.
2) The Hypothalamus stimulates sympathetic neurons directly to the adrenal medulla during fight or flight.
3) The Hypothalamus produces regulatory hormones which have an effect on the anterior pituitary gland.
448
What is the largest gland in the anterior neck?
Thyroid gland
449
Describe the gross anatomy of the Thyroid gland.
-Two lobes, connected by isthmus
-Copious blood supply
450
Describe the microscopic anatomy of the Thyroid Gland.
-Spherical follicles surrounded by numerous capillaries
-Walls of the follicles are made of simple cuboidal epithelium, with a central lumen filled with a jelly-like substance called "colloid".
451
What does the Colloid contain?
Contains Thyroglobulin, which is a protein that helps to produce Thyroid Hormone.
452
Describe Thyroid Hormone Production.
1) Hypothalamus triggers the release of Thyroid-Stimulating Hormone (TSH) from the anterior lobe of the pituitary gland.
2) Follicular cells make secrete TH.
3) TH diffuses out of the follicular cells into the surrounding capillaries.
4) This increases basal metabolic rate.
453
What is the effect of Thyroid Hormone?
Increases basal metabolic rate
454
What is an essential nutrient for Thyroid Hormone production?
The Thyroid Gland requires IODINE for TH production.
455
What is Hyperthyroidism?
This is an overactive thyroid gland. It is an autoimmune disease in which the immune system produces antibodies that stimulate Thyroid Hormone secretion.
456
What are the symptoms associated with Hyperthyroidism?
-Elevated heart rate
-Weight loss
-Elevated metabolic rate
-Protruding eyeballs due to edema
457
Where are Parathyroid Glands located?
There are 4 Parathyroid Glands located on the posterior Thyroid Gland.
458
What do Parathyroid Glands do?
Produces Parathyroid Hormone (PTH), which regulates Calcium levels in the blood.
459
T/F: The Parathyroid Glands are under the control of the Hypothalamus.
False! Parathyroid Glands are NOT under the control of Hypothalamus.
460
Describe how Parathyroid Hormone increases calcium levels if blood calcium levels are low.
PTH is released into the blood. Osteoclasts release calcium from the bone via reabsorption. Increase absorption of calcium from the tubular fluid in the kidney. The small intestine absorbs more calcium.
461
Where are Adrenal Glands located?
Located on the superior border of each kidney, also called suprarenal glands.
462
Describe the microscopic anatomy of Adrenal Glands.
-Centrally located adrenal medulla made of neural crest cells
-External adrenal cortex (with 3 zones) surrounding the medulla
463
For Adrenal Glands, how we distinguish the 3 external adrenal cortex zones? Name them and what each secretes.
Each zone is distinguishable by the amount of dye it takes up.
Zona Glomerulosa: Mineralocorticoids
Zona Fasciculata: Glucocorticoids
Zona Reticularis: Adrenal androgens
464
What does short-term stress of the Adrenal Glands cause?
Chromaffin cells in the Medulla act as a post-synaptic neuron and release epinephrine and norepinephrine into the bloodstream.
465
What does long-term stress of the Adrenal Glands cause in each zone of the Cortex?
Zone Glomerulosa: Increases water absorption in the kidney to maintain BP.
Zone Fasciculata: Maintains high blood glucose levels.
Zona Reticularis: Counter act stress, boost immunity, and make you happy.
466
Where is the Pancreas located? What artery runs directly through it?
Located in the posterior wall of the abdomen, behind the stomach. It is found spooning inside the Duodenum.
The Splenic artery runs directly through it.
467
T/F: The Pancreas contains both exocrine and endocrine cells.
True! The Exocrine cells stain darker and the Endocrine cells have islets containing alpha and beta cells.
468
What do Alpha Cells do?
Secrete Glucagon which leads to the production of glucose. Glucose enters the blood stream and raises blood sugar levels when they fall too low.
469
What do Beta Cells do?
Secrete Insulin that signals cells of the body to take up Glucose from the blood and store it. This promotes the storage of Glucose as Glycogen in the liver, thus lowering excessive blood sugar levels.
470
Where is the Thymus located?
Located in the superior mediastinum; atrophies (diminishes) during adolescence.
471
Describe the microscopic anatomy of the Thymus.
Epithelial reticular cells with a rosy appearance.
472
What do epithelial reticular cells in the Thymus secrete?
Secrete Thymic hormones
473
What stimulates maturation and immunocompetence of T cells?
Stimulated by thymic hormones.
474
What is the main source of steroid sex hormones?
The testes and ovaries are the main source of steroid sex hormones.
475
What does Testosterone do?
Maintains reproductive organs and secondary sex characteristics. Also, promotes sperm formation.
476
What do Interstitial endocrine cells in the Testes do?
Secrete Androgens, primarily Testosterone
477
What do Ovarian Follicle Cells do?
Androgens are secreted and converted into estrogen and progesterone by ovarian follicle cells.
478
What does Estrogen do?
Maintains the reproductive organs and secondary sex characteristics.
479
What does Progesterone do?
Signals the uterus to prepare for pregnancy.
480
What are 3 ways in which we can reference sex?
Genotypical (biological) sex, Phenotypical sex, and Intersex.
481
What is Genotypical (biological) Sex?
These are the sex chromosomes, so XY for a male and XX for a female.
482
What is Phenotypical Sex?
An individual's sex as determined by their internal and external genitalia, expression of secondary sex characteristics, and behavior.
483
Genotype predetermines what?
Predetermines Phenotypical Sex. This is because chromosomes determine what hormones are produced, which contribute to the formation of sex characteristics.
484
What is Intersex?
A general term used for a variety of situations in which a person is born with reproductive or sexual anatomy that doesn't fit the boxes of "female" or "male".
Basically, this is on a continuous spectrum that is atypical of male or female anatomy.
485
When studying anatomy, do we need to assign a sex? Why?
No, we do not need to assign a sex. This is because we are studying the STRUCTURES of the body.
486
When studying anatomy, what organs are we referencing and what are we not?
We are referencing the organs we can SEE, NOT the organs we EXPECT to see.
487
When discussing skeletal structure, what way can we reference sex? Why?
Genotypical sex
This is because hormones generated by the sex chromosomes are responsible for producing specific changes to bony structures.
488
Organs and structures associated with the reproductive system are located within and supported by the _________ ________________, as well as attached to it.
bony pelvis
489
What are the primary organs of reproduction? What is their function?
Testes and Ovaries.
They produce gametes and hormones.
490
What are the secondary organs of reproduction? What is their function?
Everything else besides the testes and ovaries.
Receives, stores, transports, and supports the gametes. They help with fertilization.
491
How many bones make up the adult pelvis? Name them.
4 bones make up the adult pelvis:
-Sacrum
-Coccyx
-Bilateral Os Coxae
492
What are the 3 parts of the Os Coxae?
Ischium, Ilium, and Pubis
493
How does each Ox Coxae form relative to the other?
Each bone of the Os Coxae develops independent of one another from a separate ossification center. The bones then grow towards each other with a loss of cartilage when they fuse. Fusion of the bones forms the acetabulum.
494
Label:
-Obturator foramen
-Ischial spine
-Ischial tuberosity
-Greater sciatic notch
-Lesser sciatic notch
495
What 3 ligaments provide ligamentous support of the pelvis?
Sacroiliac ligaments, sacrospinous ligament, and sacrotuberous ligament.
496
What do the Sacroiliac ligaments connect? Where do they run?
Run from sacrum to ilium anterior and posterior.
497
What does the Sacrospinous ligament connect?
Connects sacrum to ischial spine
498
What does the Sacrotuberous ligament connect? What does it close off and what does this create?
Connects sacrum to ischial tuberosity
This ligament closes off the greater and lesser sciatic notches to create the greater sciatic foramen and the lesser sciatic foramen.
499
Why is it important that the greater sciatic foramen and lesser sciatic foramen are there?
These foramen create safe passages through which structures can exit and enter the pelvis.
500
What 5 structures enter and exit the Greater Sciatic Foramen?
-Piriformis muscle
-Superior gluteal a and n
-Inferior gluteal a and n
-Sciatic nerve
-Pudendal n and a (exits pelvis)
501
What nerve and artery stimulate/supply the external and internal genitalia?
Pudendal n and a
502
What 2 structures enter/exit the Lesser Sciatic Foramen?
-Obturator internus muscle
-Pudendal n and a (re-enters pelvis)
503
What nerve and artery exit the pelvis at the Greater Sciatic Foramen and re-enters the pelvis at the Lesser Sciatic Foramen?
Pudendal n and a
504
What does the Pelvic Inlet (Superior Pelvic Aperture) form?
Forms the anatomical limit/division between the true and false pelvis.
505
What is the Pelvic Outlet (Inferior Pelvic Aperture)?
The inferior margin of the lesser pelvic cavity.
506
What is the Subpubic Angle?
The angle formed at the pubic arch by the convergence of the ischiopubic rami.
This is the angle that looks like an upside down U or V when you look at the pubic symphysis anteriorly.
507
What does the False Pelvis support? What bone of the Os Coxae is the False Pelvis?
The ilium support the organs of the abdomen.
508
What does the True Pelvis support?
Supports the organs of the pelvis.
509
What is the Perineum of the pelvis? What 4 bones are part of it?
Diamond-shape region on the pelvis looking from superior angle.
Formed by:
-Pubic symphysis
-Ischial tuberosity (left)
-Ischial tuberosity (right)
-Tip of the coccyx
510
A line drawn between the ischial tuberosities divides the perineum into what?
-Anterior Urogenital triangle
-Posterior Anal triangle
511
What muscle acts as a major stabilizer of the hip?
Obturator internus muscle
512
What is the origin and insertion of the Obturator Internus muscle?
Origin: Obturator membrane and pubic ramus
Insertion: Greater trochanter
Makes a 90 degree angle around the ischial tuberosity
513
What action does the Obturator Internus muscle perform?
Lateral rotator of the thigh at the hip; Abduction of the thigh at hip
514
What 2 muscles comprise the Pelvic Floor (aka Pelvis Diaphragm)?
Coccygeus muscle and Levator Ani muscle
515
What is the origin and insertion of the Coccygeus muscle?
Origin: Sacrum and coccyx
Insertion: Sacrospinous ligament
516
What is the origin and insertion of the Levator Ani muscle?
Origin: Tendinous arch of Levator Ani
Insertion: Pubic bones anteriorly, ischial spines posteriorly
517
What do the muscle fibers of the Levator Ani muscle form?
Muscle fibers form a hammock which supports the pelvic organs.
518
How many muscles take up the Levator Ani muscle? Name them.
Levator Ani is made up of 3 different muscles that work together to support the organs of the pelvis.
-Puborectalis
-Pubococcygeus
-Ilicoccygeus
519
What does the Puborectalis contribute?
It contributes slips of muscle that wrap around the anal, urethral, and vaginal orifice.
520
How does Levator Ani contribute to continence?
Levator Ani contributes slips of muscle that surround the anal canal and the urethra. These slips of muscle create the external urethral and external anal sphincter, which are under voluntary control.
521
Why are there gaps or hiatuses in the Pelvic Diaphragm?
These allow structures to pass through Levator Ani to the outside of the body.
522
Name the 2 hiatuses in the Pelvic Diaphragm.
Urogenital Hiatus and Anal Hiatus
523
What structures pass through the Urogenital Hiatus?
Urethra and Vaginal Canal
524
What structure passes through the Anal Hiatus?
Anal Canal
525
Name the organs within the pelvis from anterior to posterior.
-Bladder (prostate then seminal vesicle if male)
-Uterus (if female)
-Rectum
526
What type of lining covers the organs of the pelvis?
Peritoneal lining covers the organs of the pelvis.
527
What does the peritoneal lining covering the organs of the pelvis form in the Uterine and Prostate?
Uterine: Broad ligament, and Vesicouterine and Rectouterine pouches
Prostatic: Rectovesical pouch
528
What do the Vesicouterine, Rectouterine, and Rectovesical pouches do?
Collect fluid and breed bacteria
529
T/F: The organs within the pelvis have a retroperitoneal lining.
True!
530
Describe the blood supply to the pelvis beginning at the abdominal aorta.
Abdominal aorta --> Common iliac arteries --> Internal iliac artery
Internal iliac artery supplies the pelvic viscera and targets outside the pelvis.
531
What are the 4 branches of the Internal Iliac artery?
Superior gluteal artery, Inferior gluteal artery, Obturator artery, and Internal Pudendal artery.
532
What does the Superior Gluteal artery supply?
Gluteus minimus and medius
533
What does the Inferior Gluteal artery supply?
Gluteus maximus
534
What does the Obturator artery supply?
Medial compartment of the thigh (Adductors)
535
What does the Internal Pudendal artery supply?
External genitalia
536
Where does the Internal Pudendal artery exit and re-enter the pelvis at?
Exits through the Greater Sciatic Foramen and re-enters through the Lesser Sciatic Foramen.
537
Where does the Internal Pudendal artery travel through before branching into several arteries that target the external genitalia?
Travels through the Pudendal Canal
538
What is the target of the Internal Pudendal artery?
Targets structures within the Urogenital and Anal triangle.
539
What provides somatic motor and sensory innervation to the pelvis?
Pudendal nerve
540
What does the Pudendal nerve travel with?
Travels with the Pudendal artery
541
What does the Pudendal nerve do?
Provides somatic motor and sensory innervation to the pelvis
542
Where does the Pudendal nerve stem from?
From S2-4
543
What nerve maintains erection?
Pudendal nerve
544
What 3 things does the Pudendal nerve provide somatic motor innervation for?
-Muscles of the pelvic floor
-External urethral and anal sphincters
-Muscles covering the erectile tissues
545
What does the Pudendal nerve provide sensory innervation for?
Sensation from the external genitalia
546
What does the Pudendal nerve target?
Targets within the Urogenital and Anal triangle
547
What provides sympathetic innervation to the pelvis?
Superior hypogastric plexus
548
What does sympathetic innervation to the pelvis do?
"Sympathetic = Shooting"
Ejaculation and contraction of the internal urethral and anal sphincters
549
What provides parasympathetic innervation to the pelvis?
Pelvis splanchnic nerves from S2-4
550
What does parasympathetic innervation to the pelvis do?
"Para = Point"
Erection of erectile tissues and relaxation of the internal urethral and anal sphincters.
551
What is the primary function of the pelvis? What about the secondary function?
Primary Function: Protection
--> Structure of the bony pelvis protects vital organs of the pelvis, abdomen, and developing embryos.
Secondary Function: Locomotion
552
Describe 3 things about the Quadrupedal Pelvis.
-Ilium is lateral to and parallel to the vertebral column
-Ischium extends dorsally
-Sacral vertebrae lie superior to the pubic symphysis
553
Describe 2 ways in which the Bipedal Pelvis is different from the Quadrupedal Pelvis.
-Wider pelvis to support body weight and place the legs under the body
-Ilium is shorter, wider, and expanded front to back.
554
How do we determine when Bipedalism first begin?
We can look at the shape of the pelvis and determine when it begins to look like modern Homo Sapiens.
555
While Bipedalism is a very useful form of locomotion, what has been a disadvantage to it?
The pelvic shape evolved with the sacrum and pubic symphysis opposite each other, which results in challenges when birthing a child (Obstetric Challenges).
556
Describe how birthing happens with a Quadruped pelvis.
Babies head passes the sacrum before entering the birth canal. This is easier for birthing.
557
Describe how birthing happens with a Biped pelvis and why this is more difficult than with a Quadruped pelvis.
Babies head must pass between 2 bones at the same time, which restricts the birth canal and makes birthing more difficult.
558
T/F: We are still experiencing all of the obstetric (birthing) challenges originally experienced.
False! While there are still challenges with birthing, evolution of the pelvic shape has helped to alleviate obstetric challenges.
559
What is Sexual Dimorphism?
The difference in form between individuals born with testes or ovaries.
560
T/F: By observing the shape of specific pelvic features, predictions of an individuals genotype may be possible.
Quite true! These features occur on a scale of 1-5, with 1 and 5 maintaining the most extreme examples of a specific genotype.
561
Describe the difference between the Sciatic Notch in an XX individual versus an XY individual.
XX- U-shaped sciatic notch
XY- V-shaped sciatic notch
562
Describe the difference between the Iliac Crest in an XX individual versus an XY individual.
XX- Flatter, shorter
XY- Taller, rounder
563
Describe the difference between the Subpubic Angle in an XX individual versus an XY individual.
XX- U-shaped, angle is greater than 80 degrees
XY- V-shaped, angle is less than 70 degrees
564
Describe the difference between the Acetabulum in an XX individual versus an XY individual.
XX- Shallower and wider
XY- Oriented more laterally and deeper
565
Describe the difference between the Iliopubic Ramus in an XX individual versus an XY individual.
XX- Longer, rounder, longer compared to the diameter of the Acetabulum.
XY- Shorter, sharper edge, length is equal to the diameter of the Acetabulum.
566
Prediction of genotype based on the Pelvis is only possible when?
Only possible when comparing an unknown pelvis to a pelvis maintaining all of the extreme characteristics.
567
T/F: XX individuals have reduced tolerance for hip fracture compared to XY individuals.
False! XY individuals actually have the reduced tolerance for hip fractures. This is because there are statistically significant differences between pelvis shape for XX and XY. XY have a narrow pelvis which can be more prone to hip fractures.
568
In embryonic development, what accounts for the differences in Pelvic form? When are these differences visible?
Hormones influence Pelvic shape. These differences are visible during development but become more pronounced during puberty.
569
What are Puberty Blockers?
Also called Hormone Blockers, these delay or stop puberty-related changes in your body.
570
What is Hormone Replacement Therapy?
This is when you take hormones to develop secondary sex characteristics that better align with your gender identity, before or after puberty.
571
Describe the difference in Hormone Replacement Therapy pre-puberty versus post-puberty for hip shape.
Hormone Replacement Therapy prior to puberty will affect the hip shape.
However, after puberty, it will not alter hip shape.
572
What structures are associated with the Urogenital Triangle?
-External urethral sphincter
-Vaginal orifice (if present)
573
What is Levator Ani covered by? What does this serve as?
Covered by the perineal membrane.
This serves as a foundation for the erectile tissues.
574
Name the 2 types of Erectile Tissues.
Cavernous & Spongy
575
Name 4 general features of Erectile Tissues.
-Highly vascularized, sinusoidal tissues
-Smooth muscle (blood enters when relaxed)
-Extensive nerve endings
-Surrounded by a layer of connective tissue called the Tunica Albuginea
576
What is the function of Cavernous tissue?
Erection
577
What is the function of Spongy tissue?
Patency (keep open and expanded), becomes less turgid
578
What is the structural variation of Cavernous tissue?
Thicker Tunica Albuginea, tissue maintains larger sinusoids than Spongy tissue.
579
Why would it be important for Cavernous tissue to have larger sinusoids than Spongy tissue?
Larger and more abundant sinusoids allow for blood to enter and cause an erection, which is the function of Cavernous tissue.
580
What is the structural variation of Spongy tissue?
Thinner Tunica Albuginea, tissue maintains smaller sinusoids than Cavernosum tissue.
581
Why would it make sense that we would need smaller sinusoids in Spongy tissue than in Cavernosum tissue?
We don't want to close off the Urethra, thus, it is not necessary to have as much blood flow here as in the Cavernosum tissue.
582
T/F: The penis is formed by only Cavernosum tissue.
False! The penis is formed by both Cavernosum and Spongy erectile tissues.
583
Describe how the Cavernous erectile tissue contributes to the body of the penis.
There are 2 crura attached to the inferior pubic ramus. These 2 will merge past the pubic bone to form Corpora Cavernosa, which is the body of the penis. This is then surrounded by Tunica Albuginea.
584
Describe how the Spongy erectile tissue contributes to the body of the penis.
The Spongy erectile tissue attaches to the perineal membrane and joins the Corpora Cavernosa. It will grow in the space between the 2 cylinders. The penile urethra will then run through the Spongy erectile tissue.
585
What makes up the Body of the Penis?
2 cylinders of Corpus Cavernosum to form the Corpus Cavernosum.
1 cylinder of Bulbospongiosum/Corpus Spongiosum
586
What makes up the Root of the Penis?
2 Crura of Cavernosum erectile tissue
Bulb of the penis
587
What is the cavernous erectile tissue attached to both ischiopubic rami called? What does this merge to form in individuals with ovaries?
Called crura, meaning leg.
Each crura merge at the pubic symphysis to form the body of the clitoris.
588
What does the Body of the Clitoris expand to form?
Body of the clitoris expands and forms the glans of the clitoris.
589
What is the spongy erectile tissue supported by the perineal membrane referred to as?
The bulb of the vestibule
590
Where do the bulbs lie in relation to the vagina? What happens to them during sexual arousal?
Two bulbs lie on either side of the vestibule of the vagina.
Bulbs become erect during sexual arousal and compress the vaginal opening.
591
What muscle covers the cavernous erectile tissues?
Ischiocavernosus muscle
592
What muscle covers the spongy erectile tissues?
Bulbospongiosus muscle
593
How does muscle contraction affect blood vessels? Why is this good?
Muscle contraction compresses blood vessels to maintain erection.
594
Describe how an erection of cavernous and spongy tissues occur.
Erectile tissues are loaded with blood vessels. When blood fills the tissues, they become erect. Muscles surrounding the tissue will contract to hold blood in, which maintains erection.
595
T/F: Penile and Clitoral erectile dysfunction have both been studied vigorously.
False! There has been a lot of research on Penile erectile dysfunction with lots of solutions. However, Clitoral erectile dysfunction has barely been studied and there are no good solutions.
Shocking.
596
What is Sexual Dysfunction? Who can this happen to?
Occurs when erection is not achieved.
This can happen to anyone with erectile tissues.
597
Who has Sexual Dysfunction been studied and treated in?
Better studied and treated in dysfunction associated with the penis.
598
What can Sexual Dysfunction often be a symptom of?
An underlying problem such as hormone imbalance, depression, heart disease, etc.
599
What are the penis and scrotum covered by?
Erectile tissues covered most superficially by the skin.
600
What is the Scrotum?
An extension of the abdominal wall that is a pouch of skin in which the testes and spermatic cord reside.
601
What are the layers of the Scrotum? What is the function of this?
Layers of the scrotum include Cremaster and Dartos muscle.
These maintain temperature in the testes for spermatogenesis to occur.
602
What type of muscle are the Cremaster and Dartos muscle? How do they help to regulate temperature?
They are SMOOTH muscles that contract (when cold) and relax (when hot) to bring the testes closer or farther from the body to regulate ideal temperature required for spermatogenesis.
603
Where are the Cremaster and Dartos muscles located?
Cremaster muscle is in the Spermatic Cord.
Dartos Fascia is in the Scrotum.
604
What is the fatpad overlying the pubic bone called?
Mons pubis
605
In individuals with ovaries, what do the Greater Vestibular glands do?
These secrete a vaginal lubricant.
606
In individuals with ovaries, what do the Paraurethral glands do?
Lubricates the urethral opening. The lubricant is antimicrobial and is also the source of ejaculate.
607
In males, what is the primary sex organ?
Testes
608
What do Testes produce?
Produces sperm and hormones
609
Where are the Testes found?
Scrotum
610
What are the Testes surrounded by within the Scrotum?
Surrounded by the Tunica Albuginea which invaginate to form septa that create lobules.
611
Describe the internal structure of the Testes.
There are lobules that contain Seminiferous Tubules, which support sperm development. These Tubules will converge into 1 tubule leading to the Epididymis.
612
What gets developed within the Seminiferous Tubules?
Sperm
613
After the sperm are produced in the Seminiferous Tubules, where do they move? Why?
After production, they move to the Epididymis where they will mature, learn to swim, and are stored.
614
Where does the Gonadal artery originate?
Originates from the Abdominal Aorta
615
What does the Pampiniform Plexus merge to form?
Merges to form Gonadal vein
616
What is a continuation of the epididymis that travels to the abdomen?
Vas Deferens
617
What is the Inguinal Canal?
Space within the inguinal ligament that allows structures to pass from the inside to the outside of the body.
618
How is the Inguinal Canal formed?
Formed by the rolling of the abdominal muscles as they form the inguinal ligament and stretch from the anterior superior iliac spine to the pubic tubercle.
619
In regards to the Inguinal Ligament, why do the abdominal muscles roll?
Allows more Surface Area to attach to as well as keeps it tighter to keep guts in.
620
What is the internal opening of the Inguinal Canal called? What does it allow?
Deep Inguinal Ring
Allows structures to enter the canal.
621
What is the external opening of the Inguinal Canal? What does it allow?
Superficial Inguinal Ring
Allows structures to exit the canal.
622
What structures enter the Inguinal Canal through the deep ring?
Testes, artery, vein, and vas deferens enter the Inguinal Canal through the deep ring.
623
What surrounds the structures passing through the deep ring of the Inguinal Canal?
As they pass through the ring, they are surrounded by fascia and muscle originating from the abdominal wall.
624
What structures exit the Superficial Ring?
Testes, artery, vein, and vas deferens.
625
When structures exit the Superficial Ring, what are they surrounded by?
Exit the Superficial Ring surrounded by the Spermatic Cord.
626
Nerves from the ______________ abdominal wall become embedded within the spermatic cord.
posterior
627
What are secondary sex organs associated with in males?
Associated with semen transport.
628
What is the Epididymis?
Tightly coiled tube made of smooth muscle.
629
What are the 3 major functions of the Epididymis?
1) Monitors and adjusts the fluid of all the seminiferous tubules for hormones, temperature, etc.
2) Recycles damaged sperm
3) Stores capacitated sperm
630
What is the continuation of the Epididymis?
Ductus (vas) deferens
631
What is the vas deferens made of? What does it do?
Made of 2 layers of smooth muscle (for unidirectionality)
Contractions propel sperm and fluid through the duct.
632
Describe the location of the vas deferens.
Extends from the Epididymis and descends along the posterior surface of the urinary bladder towards the prostate gland.
633
Once the vas deferens reaches the area near the prostate gland, what happens?
The vas deferens dilates forming an ampulla. The ampulla joins the seminal vesicle which contributes to seminal fluid.
634
What does the ampulla of the vas deferens contribute to the seminal fluid?
Fructose, Prostaglandins (contraction of uterus), enzymes (reduce immunity at cervix), and pigment.
635
What 2 things comprise the ejaculatory duct?
The joining of the seminal vesicle and vas deferens form the ejaculatory duct.
636
As the ejaculatory duct moves through the prostate, what does it collect?
It collects prostatic fluid containing enzymes.
637
What do the enzymes from the prostatic fluid do?
-Enhance sperm motility
-Clot and liquefy ejaculated semen
-Prostate specific antigen (PSA) secreted for liquefying semen
638
Ejaculatory fluid flows through the ______________ urethra and into the ______________ urethra.
prostatic, penile
639
What are Bulbourethral glands?
Small glands embedded in the external urethral sphincter.
640
What do Bulbourethral glands do?
Secrete lubricating fluid which helps semen to pass through the urethra to the vagina.
641
What is a Vasectomy?
A permanent form of birth control in which the vas deferens is cut. Thus, sperm is removed from the semen.
642
What is Semen?
All fluid contributed by structures as it passes through the ejaculatory duct.
643
What is the primary sex organ in females?
Ovaries
644
What do Ovaries do?
Responsible for the production of oocytes and secreting hormones.
645
Describe the Ovarian structure.
Flat oval, 5 cm long, 2.5 cm wide
646
What are the Ovaries covered by?
Covered by the Tunica Albuginea
647
How is the interior tissue of the Ovaries divided?
Divided into a cortex and medulla
648
In what part of the ovarian cortex are the gametes produced?
Produced in the cortex
649
Each ovary is stabilized by 2 ligaments. What are they?
Suspensory ligament and Ovarian ligament
650
What is the Suspensory ligament?
A fold of peritoneum that extends from the lateral pelvic wall to the ovary.
651
What does the Suspensory ligament contain?
Contains the ovarian artery and vein.
652
What is the Ovarian ligament?
Extends from the lateral side of the uterus to the ovary and positions the ovary close to the uterine tube.
653
Where does the Ovarian artery branch off of? What does it supply?
Branches off of the abdominal aorta to supply blood to the Ovary.
654
Where do the Ovarian veins drain into?
On the right side of the body, the vein drains directly into the inferior vena cava.
On the left side of the body, the vein drains into the left renal vein.
655
In females, what is the Reproductive Tract associated with?
Associated with storage, nourishment, and transport of the oocyte.
656
What is the Ovarian Cycle?
A monthly series of events, directed by hormones, that result in the maturation and release of an oocyte.
657
What coaxes the oocyte into the uterine tube?
Fimbriae
658
The uterine tube is a hollow muscular tube. What 4 structures does the uterine tube contain?
Fimbriae, infundibulum, ampulla, and isthmus
659
Within the uterine tube, where does fertilization occur?
Ampulla
660
What structure in the uterine tube connects to the uterine wall?
Isthmus
661
Describe the appearance and general location of the uterus.
Pear-shaped organ found tipped over the bladder and being spooned by the rectum.
662
There are 3 stabilizing ligaments of the uterus. Name them.
Round ligament, Transverse cervical ligament, and Uterosacral ligament.
663
Where does the round ligament connect?
Lateral uterus to the mons pubis by the labia majora.
664
Where does the transverse cervical ligament connect?
Base of the uterus to the lateral pelvic wall.
665
Where does the uterosacral ligament connect?
Posterior/inferior uterus to the sacrum.
666
What is the body of the uterus made of?
Made of the myometrium and the endometrium
667
Describe the structure of the body of the uterus?
Myometrium = thick, outer muscle layer
Endometrium = Within, glandular tissue
668
What is shed during menstruation?
The glandular tissue of the Endometrium in the uterus.
669
What does the Cervix produce?
Produces copious amounts of mucus that change throughout the monthly cycle.
670
How does the mucus from the Cervix change throughout the monthly cycle?
Thin and watery during ovulation to allow passage of sperm.
Thick mucus acts as a barrier to stop pathogens from entering the uterus.
671
What is Effacement?
The thinning of the cervix as labor begins.
672
What is the dilation of the cervix?
Refers to the opening of the cervix so the baby can pass into the birth canal.
673
What is the Vagina?
An elastic, muscular tube extending from the cervix to the vestibule.
674
What are the 2 functions of the Vagina?
Passage for fluids and then passage for babies
675
What type of environment does the Vagina maintain? What is the purpose of this?
The vagina maintains an acidic environment that controls pathogens, such as Lactobacillus, which is a probiotic found in the gut and vagina.
676
When Lactobacillus is out of control in the vagina, what is the result?
A yeast infection
677
What is a Hysterectomy?
Surgical excision of the uterus and cervix. Sometimes, it can include the removal of the ovaries and uterine tube.
678
What was a popular diagnosis in the Victorian Era?
Female Hysteria
679
What system is the development of reproductive organs called?
Indifferent Duct System
680
What happens in the 5th week of Indifferent Duct System development?
Gonads begin to develop in the 5th week as masses of the urogenital ridge including the Mesonephric duct and the Paramesonephric duct.
681
When do the Mesonephric and Paramesonephric duct begin to develop?
During the 5th week
682
During the 6th week of development in the Indifferent Duct System?
Cells infiltrate the gonad that will differentiate into either spermatogonia or oogonia.
683
Gonads with spermatogonia develop into what? What is required?
Develop into testes.
The presence of the SRY protein is required for the testes to develop.
684
Gonads with oogonia will develop into what?
Develop into ovaries.
685
T/F: Individuals with testes retain the Paramesonephric duct.
False! Individuals with testes retain the Mesonephric duct, which will turn into the penis and associated structures.
686
T/F: Individuals with ovaries retain the Paramesonephric duct.
True! This will turn into the uterus and associated structures.
687
What is Endometriosis caused by?
Caused by transported endometrial tissue that creates lesions on the organs of the pelvis and abdomen.
688
T/F: The diagnosis for Endometriosis may take 7-10 years.
True! It can take a while for symptoms to appear but also, other diagnoses must be ruled out.
689
What are symptoms of Endometriosis?
Life-impacting pain during periods, sexual intercourse, bowel movements and/or urination, chronic pelvic pain, abdominal bloating, nausea, fatigue, and sometimes depression, anxiety, and infertility.
690
What does Endometriosis present as?
Presents as lesions on the organs of the pelvis and abdomen.
691
How do we treat Endometriosis?
Its aimed at reducing pain and improving quality of life.
