Anatomy Final Flashcards
What are the functions of the cardiovascular system?
Responsible for transporting blood throughout the body. Blood transports oxygen, nutrients, wastes, hormones, etc.
System of blood vessels and a heart. Heart is responsible for moving the blood
Network of blood vessels approx. 100,000 km long
What does the right side of the heart do?
Receives oxygen-poor blood from tissues
Pumps blood to lungs to get rid of CO2, pick up O2, via pulmonary circuit.
What does the left side of the heart do?
Left side receives oxygenated blood from lungs.
Pumps blood to body tissues via systemic circuit.
What are the receiving chambers of the heart?
Right atrium: Receives blood returning from systemic circuit
Left atrium: Receives blood returning from pulmonary circuit
What are the pumping chambers of the heart?
Right ventricle: pumps blood through pulmonary circuit
Left ventricle: pumps blood through systemic circuit
What separates the right ventrical from the left ventricle interiorly?
The interventricular septum
What is the heart’s position in the thoracic cavity?
left of midline, deep to sternum, mediastinum
What forms the base of the heart?
Left atrium, superior border (great vessels and superior vena cava)
What forms the apex of the heart?
Tip of left ventrical and the inferior border = right ventrical
What is the purpose of the pericardium?
Encloses the heart. Restricts movement (allows slight amount).
What are the two parts of the pericardium?
The fibrous pericardium and the serous pericardium.
Describe the serous pericardium.
One part of the pericardium. Composed on the parietal and visceral epicardium layers: pericardial cavity in between.
Where are auricles found?
In the atria. They are muscular extensions of atria. They are small, wrinkled, protruding appendages called auricles (or′ĭ-klz; auricle = little ear), which increase the atrial volume somewhat
Where is posterior sulcus located?
between the right and left ventricles
What are the functions of heart valves?
- Ensure unidirectional blood flow through heart.
- Open and close in response to pressure changes.
Why are there no valves between major veins and atria?
- Inertia of incoming blood prevents backflow.
- Heart contractions compress venous openings.
What are the two major types of heart valves?
Atrioventricular valves and semilunar valves.
Where are atrioventricular valves located?
Between atria and ventricles.
Where are semilunar valves located?
between ventricles and major arteries.
Name 2 atrioventricular valves and outline where they are located.
The tricuspid valve is the right atrioventricular valve and is between the right atria and ventricle. The mitral valve is the left AV valve, and is bicuspid. It is located between the left atria and ventricle.
What is the purpose of the atrioventricular valve? Explain how the AV valves open.
Prevent backflow into atria. When blood returning to the heart fills the atria, it presses against the AV valves. This increased pressure forces AV valves open. As the ventricles fill, the AV flaps hang limply into the ventricles. The atria contract, forcing additional blood into ventricles.
Name two structures associated with the AV valves.
Chordae tendineae (heart strings) and papillary muscles.
Describe the general systemic and pulmonary circulation.
The right side of the heart receives oxygen-poor blood from body tissues and then pumps this blood to the lungs to pick up oxygen and dispel carbon dioxide. The blood vessels that carry blood to and from the lungs form the pulmonary circuit (pulmo = lung).
The left side of the heart receives the oxygenated blood returning from the lungs and pumps this blood throughout the body to supply oxygen and nutrients to body tissues. The blood vessels that carry blood to and from all body tissues form the systemic circuit.
What is the heart wall comprised of (from superficial to deep)?
Epicardium, myocardium, and endocardium
How does blood enter the right atrium?
The superior vena cava returns blood from body regions superior to the diaphragm.
The inferior vena cava returns blood from body areas below the diaphragm.
The coronary sinus collects blood draining from the myocardium.
Define pulmonary veins.
Vessels that deliver freshly oxygenated blood from the respiratory zones of the lung to the heart.
Do the atria or the ventricles make up the most of the volume of the heart?
Ventricles
Why are the walls of the ventricles more massive than atria walls?
The ventricles are the discharging chambers, the actual pumps of the heart. Their walls are much more massive than the atrial walls, reflecting the difference in function between the atria and ventricles. When the ventricles contract, they propel blood out of the heart into the circulation.
Where does the right ventricle pump blood into?
Into the pulmonary trunk, which routes the blood to the lungs where gas exchange occurs
Where does the left ventricle eject blood into?
The aorta, the largest artery in the body.
The heart is in the mediastinum. Just what is the mediastinum?
The mediastinum is the medial cavity of the thorax within which the heart, great vessels, thymus, and parts of the trachea, bronchi, and esophagus are found.
From inside to outside, list the layers of the heart wall and the coverings of the heart.
The layers of the heart wall are the endocardium, the myocardium, and the epicardium. The epicardium is also called the visceral layer of the serous pericardium. This is surrounded by the parietal layer of the serous pericardium and the fibrous pericardium.
What is the purpose of the serous fluid inside the pericardial cavity?
The serous fluid decreases friction caused by movement of the layers against one another.
What are two heart valve disorders? What is their result and how can they be fixed?
Incompetent valve is a valve that does not close tightly, forces the heart to repump the same blood over and over because the valve does not close properly and blood backflows.
In valvular stenosis the valves become hardened. the valve flaps become stiff and constrict the opening. The constricted opening compels the heart to contract more forcibly than normal.
Both types of valve problems increase the heart’s workload and may weaken the heart severely over time. The mitral and aortic valves are most often affected.
Can be replaced by mechanical, animal or cadaver valves.
What is the function of the papillary muscles and chordae tendineae?
The papillary muscles and chordae tendineae keep the AV valve flaps from everting into the atria as the ventricles contract.
Name the valve that has just two cusps.
The mitral (left atrioventricular) valve has two cusps.
Describe the workload difference between the right and left vetricle.
Equal volumes of blood are pumped to the pulmonary and systemic circuits at any moment, but the two ventricles have very unequal workloads. The pulmonary circuit, served by the right ventricle, is a short, low-pressure circulation. In contrast, the systemic circuit, associated with the left ventricle, takes a long pathway through the entire body and encounters about five times as much friction, or resistance to blood flow.
Describe the structural differences between the left and right ventricles.
The walls of the left ventricle are three times thicker than those of the right ventricle, and its cavity is nearly circular.
The right ventricular cavity is flattened into a crescent shape that partially encloses the left ventricle, much the way a hand might loosely grasp a clenched fist.
Describe the pathway of blood through through the right side of the heart.
- Superior vena cava, inferior vena cava, coronary sinus
- right atrium
- tricuspid valve
- right ventricle
- pulmonary semilunar valve
- pulmonary trunk
- pulmonary arteries
- lungs
Describe a cardiac cycle.
Start of one heartbeat to initiation of the next. Contraction = systole and Relaxation = diastole.
Describe the pathway through the left side of the heart.
- Four pulmonary veins
- Left atrium
- Mitral valve
- Left ventricle
- Aortic semilunar valve
- Aorta
= systemic circulation
True or false? Equal volumes of blood are pumped to pulmonary and systemic circuits?
True
Which circuit involves short, low-pressure circulation?
Pulmonary circuit
Which circuit involves long, high friction circulation?
Systemic circuit
How does the heart get nourishment?
Through coronary circulation
What is coronary circulation?
The functional blood supply of the heart and the shortest circulation in the body.
What is the function of the coronary sinus?
deoxygenated blood into the right atrium.
Describe the location and function of the coronary sulcus.
The left and right coronary arteries both arise from the base of the aorta and encircle the heart in the coronary sulcus. They provide the arterial supply of the coronary circulation.
What is a myocardial infarction and what is the result?
results from the blockage in one of these vessels. results in death of tissue (heart muscle) and heart attack.
What are the two parts of the serous pericardium?
parietal and visceral layers
What are the names and locations of the four heart valves?
Atrioventricular valves: Tricuspid valve (right AV valve): between right atria and ventricle Mitral valve (left AV valve): between left atria and ventricle
Semilunar valves:
pulmonary semilunar valve: between right ventricle and pulmonary trunk
aortic semilunar valve: between left ventricle and aorta
Name the three classes of blood vessels:
arteries, veins and capillaries
Define ‘great vessels’.
The arteries and veins entering and leaving the heart.
What are the coverings of blood vessels called?
The walls of all blood vessels, except the very smallest, have three distinct layers, or tunics (“coverings”), that surround a central blood-containing space, the vessel lumen.
Describe the innermost tunic.
The innermost tunic is the tunica intima (in′tĭ-mah). The name is easy to remember once you know that this tunic is in intimate contact with the blood in the lumen. The tunica intima contains the endothelium, the simple squamous epithelium that lines the lumen of all vessels.
Describe the middle tunic.
The middle tunic, the tunica media (me′de-ah), is mostly circularly arranged smooth muscle cells and sheets of elastin.
Describe the outermost tunic of the blood vessel wall.
The outermost layer of a blood vessel wall, the tunica externa (also called the tunica adventitia; ad″ven-tish′e-ah; “coming from outside”), is composed largely of loosely woven collagen fibers that protect and reinforce the vessel, and anchor it to surrounding structures. The tunica externa is infiltrated with nerve fibers, lymphatic vessels, and, in larger veins, a network of elastic fibers. In larger vessels, the tunica externa contains a system of tiny blood vessels, the vasa vasorum (va′sah va-sor′um)—literally, “vessels of the vessels”—that nourish the more external tissues of the blood vessel wall.
Name three types of arteries.
elastic, muscular, arterioles
Which type if artery is the largest in diameter?
elastic
What does an artery do?
takes blood away from the heart
What does a vein do?
in carries blood to the heart
Which type of artery has the smallest diameter?
arterioles
Describe elastic arteries.
Largest in diameter, near the heart (the aorta and its major branches), has elastic fibers due to high pressure so needs some give; branches into muscular arteries. Elastic arteries are pressure reservoirs, expanding and recoiling as the heart ejects blood.
Describe muscular arteries.
Medium-sized; elastic fibers in two concentric rings between the three tunics: internal elastic lamina and external elastic lamina; muscular arteries have thicker tunica media.
Describe arterioles.
smallest artery type; less than six cell layers of smooth muscle in tunice media; sympathetic innervation to tunica media, which causes constriction; parasympathetic innervation causes vasodilation and lowers blood pressure.
What are the smallest blood vessels?
capillaries
Name the type of artery that matches each description: major role in dampening the pulsatile pressure of heart contractions; vasodilation or constriction determines blood flow to individual capillary beds; have the thickest tunica media relative to their lumen size.
Elastic arteries play a major role in dampening the pulsatile pressure of heart contractions. Dilation or constriction of arterioles determines blood flow to individual capillary beds. Muscular arteries have the thickest tunica media relative to their lumen size.
Which tunica does capillaries have?
Tunica intima (single layer) - need for diffusion
What leaves and what enters the capillary blood through metabolic exchange?
Oxygen, nutrients and hormones leave the capillary blood and CO2, nitrogenous wastes and other wastes enter the capillary blood.
What are the arteries and the veins entering and leaving the heart known as?
great vessels
What provides larger blood vessels with their own supply?
Vasa vasorum (tunica external)
Which branch of the autonomic nervous system innervates blood vessels? Which layer of the blood vessel wall do these nerves innervate? What are the effectors (cells that carry out the response)?
The sympathetic nervous system innervates blood vessels. The sympathetic nerves innervate the tunica media. The effector cells in the tunica media are smooth muscle cells.
When vascular smooth muscle contracts, what happens to the diameter of the blood vessel? What is this called?
When vascular smooth muscle contracts, the diameter of the blood vessel becomes smaller. This is called vasoconstriction.
Which type of artery determines blood flow to capillary beds?
Minute-to-minute blood flow into the capillary beds is determined by arteriolar diameter, which varies in response to changing neural, hormonal, and local chemical influences.
Define continuous capillaries.
Most common and least permeable. They form a complete lining. (e.g. skin, muscles and lungs)
Define fenestrated capillaries.
They contain pores that increase permeability and allow for fluid exchange (e.g. kidneys)
Define sinusoid capillaries.
The most permeable and occur in limited locations. Allows for cell and large molecule transport (e.g. spleen primarily (rbc breakdown and immune cells need to get out), bone marrow)
In the systemic circuit, which contains more blood—arteries or veins—or is it the same?
In the systemic circuit, veins contain more blood than arteries.
What is the primary function of the respiratory system?
inhalation and exhalation: exchange of O2 and CO2
What other functions does the respiratory system have besides its primary?
gas conditioning, sound production, olfaction, and defense
What sections is the upper respiratory tract divided into?
Nose and nasal cavities, paranasal sinuses and pharynx
What does the nose and nasal cavity do?
warms and humidifies the air
What do the paranasal sinuses do?
warms and humidifies the air, lightens skull and provides a resonance chamber
What two regions share the pharynx?
respiratory and digestive
What three regions is the pharynx divided into?
nasopharynx (nasal), oropharynx (oral) and laryngopharynx (‘larynx’) (listed from superior to inferior)
Where is the nasopharynx located?
continuous with nasal cavity, superior to the soft palate
Where are the pharyngotympanic (Eustacian) tubes found and what is their purpose?
In the lateral walls of the nasopharynx. Their purpose is drainage and equalizing pressure.
What is located in the posterior region of the nasopharynx and what does it contain?
The pharyngeal tonsil. It contains immune cells.
What is a tonsil?
A mass of lymphoid tissue.
What is the location of the oropharynx?
It is one region of the pharynx and is located between the soft palate and the hyoid bone.
What is located in the lateral wall of the oropharynx?
The palatine tonsils.
What is located in the oropharynx at the base of the tongue?
The lingual tonsils.
What lines the laryngopharynx?
tough epithelial
Where is the laryngopharynx located?
from the hyoid to the top of the esophagus.
Is the laryngopharynx located posteriorly or anteriorly to the larynx?
posteriorly
What is the conducting portion of the lower respiratory tract?
larynx, trachea, bronchi and bronchioles
What is the respiratory portion of the lower respiratory tract?
respiratory bronchioles, alveolar ducts, alveoli
What are the functions of the larynx?
air, blocks ingested material from respiratory tract, sound, increases pressure in the abdominal cavity and sneeze and cough reflex
What else is the larynx known as?
voice box
What is the laryngeal prominence and is the same in both genders?
It is the Adam’s apple. More prominent in men due to testosterone during development.
List the order of the anatomy of the larynx.
Epiglottis, Thyroid cartilage, laryngeal prominence, cricoid cartilage
What happens when we swallow food?
The epiglottis acts as a flap and saves you from choking on food.
What else is the trachea known as and what does it branch into?
It is known as the windpipe and branches into primary bronchi
How many C-shaped cartilages are found in the trachea and how are they connected?
16 - 20 and they are connected by anular ligaments
Why is the trachea lined with mucous-producing cells?
Prevents pathogens from entering the lungs.
Why is the bronchial tree highly branched?
To increase surface area.
Where does the bronchial tree start and end?
The bronchial tree originates in the main bronchi and terminates in the terminal bronchioles.
What is the secondary bronchi called?
lobar bronchi
What is the tertiary bronchi called?
segmental bronchi
List some characteristics of bronchioles.
- lack cartilage
- simple squamous/columnar epithelial
- < 1 mm in diameter
- walls are thick layers of smooth muscle to dilate bronchioles to bring more air in
- they branch into terminal bronchioles
Describe the structure of the trachea and its role in the body.
It branches into primary bronchi and has 16-20 C-shaped cartilages connected by anular ligaments. It acts as an air passageway, cleans, warms and moistens the incoming air.
What is the function of the bronchiole tree?
Air passageways connecting trachea with alveoli; cleans and warms the incoming air as well as moistens it
Describe the structure and function of alveoli.
Microscopic chambers at the termini of the bronchiole tree. Walls of simple squamous epithelium overlie thin basement membrane. External surfaces are intimately associated with pulmonary capillaries. They are the main site of gas exchange.
What is the path after the terminal bronchioles?
respiratory bronchioles, alveolar ducts then alveoli
Air moving from the nose to the larynx passes by a number of structures. List (in order) as many of these structures as you can.
The structures that air passes by are the nasal cavity, nasopharynx, oropharynx, and laryngopharynx.
Define the respiratory zone.
The respiratory zone, the actual site of gas exchange, is composed of the respiratory bronchioles, alveolar ducts, and alveoli, all microscopic structures.
Define the conducting zone.
The conducting zone consists of all of the respiratory passageways from the nose to the respiratory bronchioles. These provide fairly rigid conduits for air to reach the gas exchange sites. The conducting zone organs also cleanse, humidify, and warm incoming air.
What forms the respiratory membrane?
capillary and alveolar Type 1) walls and their fused basement membranes
What is the function of the respiratory membrane?
Gas exchanges occur readily by simple diffusion across the respiratory membrane—O2 passes from the alveolus into the blood, and CO2 leaves the blood to enter the gas-filled alveolus.
What are Type 1 alveolar cells?
are squamous epithelial cells that form the major part of the alveolar walls.
What are Type 2 alveolar cells?
cuboidal epithelial cells that are scattered among the type I cells. They secrete a fluid containing a detergent-like substance called surfactant that coats the gas-exposed alveolar surfaces. Breaks up water and reduces surface tension. Type II alveolar cells also secrete a number of antimicrobial proteins that are important elements of innate immunity.
Which structure seals the larynx when we swallow?
The epiglottis seals the larynx when we swallow.
Which structural features of the trachea allow it to expand and contract, yet keep it from collapsing?
The incomplete, C-shaped cartilage rings of the trachea allow it to expand and contract and yet keep it from collapsing.
What features of the alveoli and their respiratory membranes suit them to their function of exchanging gases by diffusion?
The many tiny alveoli together have a large surface area. This and the thinness of their respiratory membranes make them ideal for gas exchange.
What are the layers of the pleural membranes?
The visceral pleura tightly adheres to the outside of lung, parietal pleura lines the pleural cavity and the space in between the is the pleural cavity.
Why does the pleural cavity have negative pressure?
Although the pleurae slide easily across each other, the surface tension of the pleural fluid strongly resists their separation. Consequently, the lungs cling tightly to the thorax wall and expand and recoil passively as the volume of the thoracic cavity alternately increases and decreases during breathing. (keeps the lungs expanded)
Describe the location of the lungs.
- The anterior, lateral, and posterior lung surfaces lie in close contact with the ribs and form the continuously curving costal surface.
- Just deep to the clavicle is the apex, the narrow superior tip of the lung.
The concave, inferior surface that rests on the diaphragm is the base.
What separates the lobes of the lungs?
Fissures
How many lobes does the right lung have?
3
What are the names of the fissures in the right lung?
horizontal fissure, oblique fissure
How many lobes does the left lung have?
2
What are/is the name(s) of the fissures in the left lung?
oblique fissure
What is the hilum?
An indentation through which pulmonary and systemic blood vessels, bronchi, lymphatic vessels, and nerves enter and leave the lungs. Each main bronchus plunges into the hilum on its own side and begins to branch almost immediately.
What are all of the structures within the hilum called?
the root
Why do the two lungs differ slightly in size?
The two lungs differ slightly in shape and size because the apex of the heart is slightly to the left of the median plane. The left lung is smaller than the right, and the cardiac notch—a concavity in its medial aspect—is molded to and accommodates the heart.
What blood vessels supply and drain the lungs?
- Systemic venous blood that is to be oxygenated in the lungs is delivered by the pulmonary arteries, which lie anterior to the main bronchi.
- In the lungs, the pulmonary arteries branch profusely along with the bronchi and finally feed into the pulmonary capillary networks surrounding the alveoli
- The pulmonary veins convey the freshly oxygenated blood from the respiratory zone of the lungs to the heart. Their tributaries course back to the hilum both with the corresponding bronchi and in the connective tissue septa separating the bronchopulmonary segments.
What are the main functions of the digestive system?
- take in food
- break food down into nutrients
- absorb molecules into the bloodstream
- rid body of any indigestible remains
What organs make up the alimentary canal?
It is the muscular tube that runs from the mouth to the anus and is comprised of:
- mouth
- pharynx
- esophagus
- stomach
- small intestine
- large intestine
- anus
What are the accessory digestive organs?
- teeth
- tongue
- gallbladder
- digestive glands
Define the digestive glands and give three examples.
They produce secretions that help break down foodstuffs and include salivary glands, liver, and pancreas
Which essential activities are involved in processing food?
ingestion, propulsion, digestions, absorption, defecation (elimination)
What is propulsion?
The movement of food through the alimentary canal. swallowing in the oropharynx, peristalsis in the esophagus, stomach, small intestine and large intestine
What is absorption in the digestive system?
passage of digested fragments from lumen of GI tract into blood or lymph
What is defecation?
elimination of indigestible substances via anus in the form of feces
What is the name of the serous membranes that line the abdominopelvic cavity?
- parietal peritoneum
- visceral peritoneum
Name one organ of the alimentary canal found in the thorax. Name three organs located in the abdominal cavity.
The esophagus is found in the thorax. Three alimentary canal organs found in the abdominal cavity include the stomach, small intestine, and large intestine.
What is the usual site of ingestion?
The usual site of ingestion is the mouth.
Which digestive system activity actually moves nutrients from the outside to the inside of the body?
The process of absorption moves nutrients into the body.
What are the mesenteries and their function in the digestive system?
A mesentery (mes′en-ter″e) is a double layer of peritoneum—a sheet of two serous membranes fused back to back—that extends to the digestive organs from the body wall. Mesenteries have the following functions:
- They provide routes for blood vessels, lymphatics, and nerves to reach the digestive viscera.
- They hold organs in place.
- They store fat.
List the mesenteries.
- greater and lesser omentum (Stomach and other organs)
- mesentery proper (small intestine)
- mesocolon (large intestine)
From deep to superficial, what are the tunics of the alimentary canal?
mucosa, submucosa, muscularis, serosa (surrounded by peritoneum) or adventitia (connective tissue)
What type of muscle moves food through the alimentary canal?
smooth muscle
True or false? Digestion is both mechanical and chemical?
True
What are two examples of mechanical digestion?
chewing and churning (stomach)
What are the organs associated with the mouth?
mouth, tongue, salivary glands, teeth
Describe the mouth.
Bounded by lips anteriorly, cheeks laterally, soft and hard palate superiorly and the tongue inferiorily
What is the uvula and what does it help with?
It is a projection on the soft palate and it help block food from going back up into the nasal cavity.
What kind of cells line the walls of the mouth?
stratified squamous epithelial
What does the tongue do?
taste, aids in chewing, swallowing
What attaches the tongue to the floor of the mouth?
lingual frenulum
What connects the upper and lower lips to the mouth?
superior and inferior labial frenulum
How many teeth do we have?
32
What is the hardest substance in the body and where can it be found?
Enamel, covering the teeth.
Which teeth are chisel shaped and anterior?
incisors
Which teeth are fanglike
canines
What makes up the crown of the tooth?
enamel, dentin and pulp cavity (contains blood vessels and nerves)
What makes up the root of the tooth?
cement, periodontal ligament
What maintains the dentin of teeth?
The odontoblasts of the pulp cavity
List the three major pairs of salivary glands.
parotid glands, submandibular glands, sublingual glands
What are the functions of saliva?
cleanses mouth, dissolve food chemicals for taste, moistens food and packs it into a bolus, begins chemical breakdown
Why does the gastroesophageal sphincter close when food is not being swallowed?
- prevents stomach acid from coming up
- prevents air from entering the stomach
How does the location of the visceral peritoneum differ from that of the parietal peritoneum?
The visceral peritoneum is the outermost layer of the digestive organ; the parietal peritoneum is the serous membrane covering the wall of the abdominal cavity.
Which structure forms the roof of the mouth?
The palate forms the roof of the mouth. The hard palate supported by bone is anterior to the soft palate (no bony support).
What functions does the stomach have?
Mechanical and chemical digestion, holding area for food and turning processed bolus into chyme
List two chemical digestion chemicals associated with the stomach.
Hydrochloric acid denatures protein and pepsin digests proteins
What are the three muscular layers of the stomach?
longitudinal, circular, and oblique
List the 4 regions of the stomach.
- cardia
- fundus
- body
- pyloris
Where are the gastric folds located and what is their purpose?
They are on the internal surface of the stomach. They increase surface area and allow for greater stretch.
What layer does the surface mucosal cell belong to and what does it produce?
Mucosal layer. Produced alkaline mucous, which helps to protect the walls of the stomach from acid.
List the cells of the mucosal layer in the stomach wall.
- surface mucous cells
- mucous neck cells
- parietal cells
- chief cells
- enteroendocrine cells
What are four different types of cells in the stomach mucosa and what are their functions?
- surface mucous cells: produce alkaline mucous, which helps protect the wall of the stomach from acid
- parietal cells: produce HCl and intrinsic factor
- chief cells: produces pepsinogen and lipase
- enteroendocrine cells: produces gastrin hormone
What is the only thing in the stomach that you would die from if it didn’t happen? (maybe bonus question)
not having intrinsic factor - need it for your blood cells to be produced
List the name and a brief location description of the regions of the small intestine.
- duodenum: curves around the head of the pancreas
- jejunum: attached posteriorly by mesentery
- ileum: attached posteriorly by mesentery; joins large intestine at ileocecal valve
What 3 ways is the tissue of the small intestine modified to maximize surface area and absorption?
- circular folds (force chyme to slowly spiral through lumen)
- villi: fingerlike projections of mucosa
- microvilli: cytoplasmic extensions (brush border) of mucosal cells on villi
List three functions of the large intestine.
- absorbs remaining water
- contains mutualistic bacteria that aids in digestion
- storage and elimination of undigested food (poop)
Zach is hit in the lower back by an errant baseball. What protects his kidneys from this mechanical trauma?
The lower part of his rib cage and the perirenal fat capsule protect his kidneys from blows.
From inside to outside, list the three layers of supportive tissue that surround each kidney. Where is the parietal peritoneum in relation to these layers?
The layers of supportive tissue around each kidney are the fibrous capsule, the perirenal fat capsule, and the renal fascia. The parietal peritoneum overlies the anterior renal fascia.
The lumen of the ureter is continuous with a space inside the kidney. This space has branching extensions. What are the names of this space and its extensions?
The renal pelvis, which has extensions called calyces, is continuous with the ureter.
Name the tubular components of a nephron in the order that filtrate passes through them.
Filtrate is formed in the glomerular capsule and then passes through the proximal convoluted tubule (PCT), the descending and ascending limbs of the nephron loop, and the distal convoluted tubule (DCT).
What type of capillaries are the glomerular capillaries? What is their function?
The glomerular capillaries are fenestrated capillaries. Their function is to filter large amounts of plasma into the glomerular capsule.
Name the tubular structures in the testes that act as “sperm factories.”
The seminiferous tubules act as the sperm factories.
Name the organs of the male duct system in order, from the epididymis to the body exterior. Which of these organs runs from the scrotum into the pelvic cavity?
The organs of the male duct system in order from the epididymis to the body exterior are the ductus deferens, ejaculatory duct, prostatic urethra, intermediate part of the urethra, and spongy urethra. The ductus deferens runs from the scrotum into the pelvic cavity.
What name is given to the external region where the penis and scrotum are suspended?
The male perineum is the external region where the penis and scrotum are suspended.
What is the name of the valve that connects the small and large intestines?
Ileocecal valve
Which is longer, the small or large intesting?
Small intestine; large intestine is called large due to its diameter
What connects the small intestine to the large intestine?
The cecum connects to the ileum
What is the appendix and where is it located?
It is a mass of lymphoid tissue and is located in the large intestine.
What are the different parts of the colon?
ascending, transverse, descending and sigmoid
What is the purpose of the rectal valves?
To stop feces from being passed with gas.
How many sphincters are in the anus?
2: internal and external anal sphincters
List three accessory digestive organs and the part of the digestive system they are associated with.
Liver, gall bladder, pancreas. They are associated with the small intestine.
What are the 4 lobes of the liver? Which one extends most inferiorly?
- right lobe
- caudate lobe
- quadrate lobe
- left lobe
The right lobe extends most inferiorly.
Which lobe in the liver is more superior, the caudate lobe or the quadrate lobe?
Caudate lobe
List 4 functions of the liver.
- produced bile
- stores/processes nutrients
- detoxification (e.g. alcohol)
- hepatic portal circulation: veins from small intestine
What does bile do?
Helps digest lipids
Where is the gall bladder located?
Inferior surface of the liver
What are the functions of the gallbladder?
stores bile and concentrates bile
What connects the gallbladder to the bile duct? What does the bile duct then merge into?
Cystic duct. Bile duct merges into common hepatic duct.
What are the exocrine functions of the pancreas?
- it secretes into ducts digestive enzymes including:
- proteases
- amylase
- lipases
- nucleases
bicarbonate
What is the function of bicarbonate in the pancreas?
- it is basic
it neutralizes acid or it will damage the small intestine
What are the endocrine functions of the pancreas?
- secretes into the blood
- produces insulin and glucagon
Where do the bile duct and the pancreatic duct unite?
in the wall of the duodenum
What is the structure called where the bile duct and pancreatic duct fuse together?
hepatopancreatic ampulla
What controls entry from the hepatopancreatic ampulla into the small intestine?
the hepatopancreatic sphincter
How does the small intestine maximize surface area?
By having circular folds that make chyme spiral through the lumen. The circular folds have villi and the villi have microvilli, cytoplasmic extensions that help increase the surface area.
What digestive compounds are produced by the liver and the pancreas?
bile, lipase, protease, bicarbonate, amylase, nucleases
What may result from a blockage of the ileocecal valve?
It would back up the small intestine; nothing could enter the large intestine.
List 5 functions of the urinary system.
- storage of urine
- excretion of urine
- regulation of blood volume
- regulation of erythrocyte formation
- regulation of ion balance/acid-base balance
Why do we want to get rid of urine?
Want to get rid of urea, because it has cellular waste, specifically ones with nitrogenous waste.
Explain the location of the kidneys.
The left kidneys is at about T12 and the right kidney is 2 cm lower. The liver crowds the right kidney slightly whereas the left kidney doesn’t need to accommodate it.
What protects the kidneys?
To some extent the lower rib cage, the fibrous capsule which is connective tissue around the kidneys, and the fat that surrounds it.
Where do the vessels, nerves and ureters enter the kidneys?
the hilum
What is contained within the renal sinus?
minor calyx, major calyx, renal pelvis and ureter
True or false: the cortex is the inner part of the kidneys.
False. The cortex is the outer part and the medulla is the inner part. The exception to this is the cortical extensions called renal columns that reach from the outer cortex deep into the kidney.
What does the medulla of the kidneys form?
The renal pyramids.
What is at the apex of the renal pyramids and what does it connect with?
Renal papilla and they are in contact with the minor calyces. Urine drains out of the renal papilla and into the minor calyces.
Describe the blood supply path from the heart to the glomerulus (capillaries) in the kidney.
Abdominal aorta - renal artery - segmental artery - interlobar artery - arcuate artery - cortical radiate artery - afferent arterioles - glomerulus (capillaries)
Describe the path of blood from the glomerulus (capillaries) in the kidney to the heart.
Glomerulus (capillaries) - efferent arterioles - peritubular capillaries or vasa recta - cortical radiate vein - arcuate vein - interlobal vein - renal vein - inferior vena cava - right atrium
What are the nephrons and how many are there?
They are the functional filtration unit of the kidney and a kidney contains about 1 million.
What are some of the main functions of the kidneys?
- filters the blood
- regulates blood volume
- regulates erythrocyte production
- regulates ion balance/acid-base balance
List the high level components of the nephron.
- renal corpuscle
- proximal convoluted tubule
- a nephron loop
a distal convoluted tubule
Where are the nephrons located within the kidney?
The nephron loop is in the medulla but everything else is mostly in the cortex.
What the nephrons lined with?
epithelial cells; they do reabsorbing into blood and secreting into filtrate.
List and describe the two parts of the renal corpuscle.
The glomerulus is highly porous capillaries covered by podocytes and forms filtrate.
The glomerular (Bowman’s) capsule surrounds the glomerulus and allows filtrate to enter.
What type of capillaries are in the glomerulus?
fenestrated - keeps large things like rbcs out
What kind of pressure drives filtration in the glomerulus?
hydrostatic pressure
What brings the blood to and from the glomerulus?
afferent arteriole bring blood to and efferent arterioles bring blood away
Which tubule is closest to the renal corpuscle?
the proximal convoluted tubule
Which tubule is the site of most molecule reabsorption.
the proximal convoluted tubule
What kinds of molecules does the proximal convoluted tubule reabsorb?
- all nutrients (glucose, amino acids, etc.)
- most sodium and water)
- many ions
What are the two parts of the nephron loop and what do they do?
- descending and ascending limbs
- both facilitate reabsorption of water and solutes
True or false. The collecting duct is considered part of the nephron.
False. Not technically part of the nephron.
What does the distal convoluted tubule secrete?
potassium and hydrogen from peritubular capillaries into tubular fluid. It also responds to hormones.
What is the urinary tract composed of?
- ureters
- urinary bladder
- urethra
What does the urinary tract do and not do?
It does transport, store and eliminate urine from the body.
It does not reabsorb anything.
Where do the ureters originate?
at renal pelvis
Where do the ureters go after they exit the hilum?
descend and enter the base of the urinary bladder
What are the layers of the ureters and what kinds if cells are associated with each layer?
- mucosa (transitional epithelium, basement membrane (lamina propria)
- muscularis (smooth muscles - longitudinal layer and circular layer)
- adventitia: outer layer
What is the function of the urinary bladder?
stored urine (temporary)
What is located in the trigone of the bladder?
- two ureteral openings
- one urethral opening
What are the four tunics of the urinary bladder?
- mucosa
- submucosa
- muscularis
- adventitia
What feature of the mucosa layer of the urinary bladder allows for distension of the bladder?
the rugae
What is the purpose of the sub mucosal layer in the urinary bladder?
supports the urinary bladder wall
Describe the muscularis layer of the urinary bladder.
It is three layers of smooth muscle. Collectively they are known as the detrusor muscle.
Describe transitional epithelium.
Its appearance changes depending upon the level of stretch. Appear squamous when stretched and columnar when not stretched.
What is the urethra?
Tube from neck of the urinary bladder to the exterior of the body.
How many sphincters does the urethra have and what are they called?
- internal urethral sphincter and external urethral phincter.
Where does urine actually exit from?
The external urethral oriface
What are 3 major functions of the kidneys?
- regulates blood volume
- production of erythrocytes
- filtration and reabsorption of nutrients and ions; helps regulate pH in blood
Where is blood filtered in the nephron? How does this process occur?
Glomerulus. Comes in through the pores (hydrostatic pressure) then into the glomerulus capsule and then on to the tubules (proximal convoluted tubule first).
What types of substances are reabsorbed in the nephron?
Na, K, water, other ions, nutrients - most things get reabsorbed that the body needs
What are the four tunics surrounding the urinary bladder?
mucosa, submucosa, muscularis and adventitial
What are the gonads (primarily sex organs) called in the male and female reproductive systems?
ovaries in females, testes in males
What do the gonads produce?
sex cells called gametes
oocytes in the female
sperm in the male
What are the accessory sex organs in the female body?
- uterine tubes
- uterus
- vagina
- clitoris
- mammary glands
What are the parts within the external genitalia of the female (the vulva)?
- mons pubis
- clitoris
- external urethral orifice
- greater vestibular gland
- labium majora
- labia minora
- vaginal orifice
How are the ovaries anchored into the pelvic cavity?
Anchored in by cords and sheets of connective tissue and the broad ligament.
What surrounds the ovaries on the surface?
Simple cuboidal cells called the surface (germinal) epithelium.
What is deep to the surface (germinal) epithelium?
tunica albuginea
What does the cortex of the ovary contain?
ovarian follicles
What does the medulla of the ovary contain?
connective tissue, blood vessels, lymph vessels, and nerves
What part of the ovary contains the oocytes?
The follicles
Where is the secondary oocyte usually fertilized?
In the lateral part of the uterine tube called to ampulla
How many days does it usually take the pre-embryo to travel the length of the uterine tube and meet the lumen of the uterus?
approximately 3 days
List the components of the uterine tube.
- fimbriae
- infundibulum
- isthmus
- ampulla
- uterine part
Describe the infundibulum of the uterine tube.
Margin of tube with projections called fimbriae.
Describe the ampulla of the uterine tube.
Medial to the infundibulum and where fertilization typically occurs.
Describe the isthmus.
Part of the uterine tube that accounts for one third of the entire length.
True or false - the uterine part is continuous with the uterus.
True. It connects to the uterus and the isthmus.
Describe the uterus.
Pear-shaped, thick-walled, muscular organ; lumen of the uterus is continuous with the uterine tubes and vagina.
What are the functions of the uterus?
- site of implantation
- supports and protects the developing embryo/fetus
- ejects the fetus during labour
From superior to inferior, list the regions of the uterus.
- fundus
- body
- isthmus
- cervix
What region of the uterus is the major part with thick walls?
body
What region of the uterus is a constricted segment?
The isthmus. It is located between the body and the cervix.
What region of the uterus is narrow and projects into the vagina?
the cervix
What are the three layers of the uterine wall, from deep to superficial?
- endometrium
- myometrium
- perimetrium
What are the three layers of the uterine wall composed of?
- perimetrium: composed of serosa
- myometrium: composed of smooth muscle
- endometrium: mucosa with 2 layers:
- basal layer: doesn’t change much during the uterine cycle
- functional layer: changes thickness during the uterine cycle and is shed if not fertilized
Which layer of the endometrium thickens during the uterine cycle?
The functional layer
Describe the vagina.
A fibromuscular tube about 10 cm in length.
What is found near the opening of the vagina (the vaginal orifice)?
Folds of the mucosa form a membranous barrier called the hymen.
What is the mons pubis?
It is part of the external genitalia of the female. It is skin and subcutaneous connective tissue immediately anterior to the pubic symphysis.
What are the labial majora and the labia minora?
The labia majora are paired, thickened folds of skin. The labia minora are also paired folds of skin and they are medial to the labia majora.
What is the space between the labia minora called?
the vestibule
What is found within the vestibule of the vulva?
urethral opening and the vaginal orifice
How is the vagina lubricated?
By a pair of glands called the greater vestibular glands. They secrete mucin to lubricate the vagina. They are located more posteriorly.
Where is the clitoris located and explain its structure.
The clitoris is located at anterior regions of the labia minora. Two small erectile bodies called the corpora cavernosa form the body of the clitoris. It fills with blood similar to the penis.
What are mammary glands?
Exocrine glands that function to produce and secrete milk.
What do the lobules of the mammary glands contain and what do they do?
The lobules contain secretory units called alveoli that produce milk.
How does the milk move out from the alveoli in the lobules?
The milk drains from the alveoli into lactiferous ducts, which then expand into lactiferous sinuses as they approach the nipple.
What does the cortex of the ovaries contain? What is the purpose of these cells?
The cortex contains the ovarian follicles. The purpose of the follicles is to contain the oocytes, the female gamete, and release one per month.
Which layer of the uterus is shed during mentruation?
the endometrium (the functional layer)
What are the different parts of the uterine tube? Which part does fertilization usually occur?
fimbriae, infundibulum, ampulla, isthmus, and uterine part. Fertilization usually happens in the ampulla section.
What structure does milk enter directly before it reaches the nipple?
lactiferous sinuses
What is the primary male sex organ?
testes
What is the major function of the male reproductive system?
produce gametes and also produces hormones
Where are the testes located?
In the scrotum
Why are the testes located external to the body?
Sperm develop best at ~2-3 degrees Celsius below body temperature; this is best achieved by being close to the body but not in the body
What surrounds the testes?
peritoneum: the tunica albuginea is the inner layer and the tunica vaginalis is the outer layer
What do the testes divide into?
Lobules with convoluted seminiferous tubules.
Where are sperm made?
In the seminiferous tubules.
What is sperm production in the seminiferous tubules called?
spermatogenesis
What types of cell do the seminiferous tubules contain and what is their function?
- Sustentacular cells (sustentocytes): support cells
- Germ cells: dividing cells that continuously produce sperm beginning at puberty
What part of the male reproductive system receives the sperm from the seminiferous tubules and where does it send it to?
The rete testis receive sperm from the seminiferous tubules and sends it to the epididymis.
Where are the sperm cells stored and mature?
The epididymis
Where does the sperm go after leaving the epididymis?
Sperm enters the thick-walled ductus deferens (vas deferens).
What does the ductus deferens (vas deferens) enlarge to form?
The ampulla of the ductus deferens
What accessory organ produces ~70% of semen?
The seminal glands (lateral to the ampulla of the dctus deferens)
What is semen?
Alkaline fluid containing sugars for sperm. The sugars are to provide energy for movement.
Where to the ampulla of the ductus deferens unite?
They unite when they reach the ejaculatory duct (superior to the prostatic duct)
After the ejaculatory duct, where does the sperm and seminal secretions go?
the prostatic urethra
What gland accounts for 30% of semen and secretes fluid to help activate sperm?
prostate gland. It secretes into the prostatic urethra
After the prostatic urethra, where does semen travel through?
The intermediate (membranous) urethra
What do the bulbourethral glands do?
They secrete clear, viscous mucin to lubricate the urethra prior to ejaculation.
What section follows the intermediate part of the urethra?
The spongy urethra
How much ejaculate is typical?
3-5 mL and contains 200 - 500 million sperm
What forms the external genitalia in males?
the penis and the scrotum
What is the elongated portion of the penis called?
the body (shaft)
What is the tip of the penis called and what does it surround?
The tip is called the glans and it surrounds the external urethral orifice.
What is the prepuce?
The foreskin of an uncircumcised penis.
Name the three parallel, cylindrical erectile bodies contained within the shaft of the penis.
- paired corpora cavernosa are located dorsolaterally
- A single corpus spongiosum is located ventrally
What fills the parallel, cylindrical erectile bodies during erection?
Blood
What leads to ejaculation?
Waves of muscular contractions/
Please trace the pathway of blood from the heart to the hand, listing the major arteries along the way.
Ascending aorta, brachiocephalic artery, subclavian artery, axillary, brachial, ulna & radial
Which veins bring blood back from the lower limbs to the inferior vena cava?
great saphenous and femoral veins, which merge into the common iliac vein, then the inferior vena cava
If there was a blockage of the brachiocephalic trunk, which major areas of the body would be affected?
right arm and brain/head
