Week 12 (exam 4) Flashcards
What are the parts of the upper digestive system?
Buccal or oral cavity
Pharynx
Esophagus
Stomach
What separates the upper and lower digestive system?
Pyloric sphincter
What are the parts of the lower digestive tract?
Small intestines
Cecum
Large intestine or colon
Rectum
Anus
What does mechanical mean?
Chewing up food
What is the buccal or oral cavity?
Mouth- entry site for digestive tract
Chewing or Mastication
What is mastication?
Pulmonary breakdown of the food
What are the order of the teeth front to back?
Incisors
Canines
Bicuspids
Molars
What are the incisors?
Front teeth
Chisel shaped
Chop off a piece of food
What are the canines?
Next to incisors
Piercing teeth
Work with incisors
Greatly reduced
Fangs in other species
Used as weapons and way to distinguish male and female
What are the bicuspids and molars?
Flat teeth in back of mouth
Grind/ pulverize food
Where is saliva produced?
Salivary glands
What does saliva do to the food?
Lubricates and moistens the food
Makes food into a solid ball of material- bolus
Contains enzyme amylase
What is a bolus?
When saliva turns food into a solid ball of material
What is amylase?
Starch digesting enzyme
Begins chemical digestion of starch to glucose (sugar)
What is salivary amylase?
Same thing as amylase but called this because it is found in your saliva
Where does the tongue flick the bolus?
Pharynx
What is a pharynx?
Place in throat where the food and air passage ways cross
What does your trachea or windpipe have?
Rings of cartilage
Air goes down where…?
Food goes down where…?
Trachea
Esophagus
What are the 3 parts of the pharynx and explain
1) Nasopharynx- back of nasal cavity
2) Oropharynx- behind mouth and where food and air passage cross
3) Laryngopharynx- outside your voice box (larynx)
What does deglutition mean?
Swallowing
When the bolus is flipped back with the tongue, what happens after?
Pressure of the food starts swallowing reflex
What does peristalsis mean and where is it seen first?
Waves of muscular contraction that propel food through digestive tract
Seen first in esophagus
What are the 2 basic layers of smooth muscle found in your esophagus?
1) circular (laid out)
2) longitudinal
What is the circular smooth muscle?
When they contract they squeeze esophagus and food goes down
What is longitudinal smooth muscle?
Fibers running up and down following the esophagus
Shortens the esophagus allowing good to go down faster
What does the circular and longitudinal muscles do together?
Push bolus into stomach
What does lumen mean?
Hollow interior
What are the functions of the stomach?
1) holding area for food you have eaten already
2) where chemical breakdown and some mechanical breakdown happens and food liquifies here (chyme)
3) where a good deal of protein digestion takes place
What does chyme mean?
Liquified food
What does emesis mean?
Vomit
What are the 3 parts of the stomach in order?
1) Cardiac region
2) Fundic region
3) Pyloric region
What kind of cells are in the cardiac and pyloric region?
Goblet cells
What kind of cells are in the fundic region?
Parietal cells and chief cells
What are proteolytic enzymes?
Enzymes that digest proteins
Where is pepsin found and what secrets it?
Found in stomach
Secreted by chief cells but not directly
What are chief cells?
Secret Pepsinogen into stomach then converted into Pepsin
What do parietal cells secret?
Hydrochloric Acid (HCl)
What does Hydrochloric acid (HCl) do?
Denatures protein molecules by unraveling knot and pepsin chops them into amino acids
What is the optimal pH for pepsin and amylase?
Pepsin- 2
Amylase- 7
What are goblet cells?
Secret mucin (mucus) which is basic
Coating lining of stomach with mucus
What is mucus used for?
Barrier so stomach won’t digest itself
Incredibly tough
Where is the cardiac sphincter located?
Between esophagus and stomach
What is the cardiac sphincter?
Not a true sphincter and not completely effective
When stomach acid and enzymes go up to the end of the esophagus what can that cause?
Heartburn or acid reflux
What is a sphincter?
Circular and smooth
Acts like a door
What does reflux do?
Eat away wall of esophagus
What is gastritis?
Inflammation of the stomach
Either too much acid, mucus of stomach wall not effective, or not producing enough mucus
What is a gastric ulcer?
A hole digested in the wall of the stomach
What does gastro mean?
Stomach
What are some things that get absorbed in the stomach?
Water
Milk
Aspirin
Alcohol (absorbed as soon as it hits your mouth)
What is the pyloric sphincter?
Between stomach and small intestine
Distinct circular smooth muscle
If it is closed nothing goes through it
If opened things can go through
Only something liquified or small particles can get through
A true sphincter
What is the dyodenum?
Beginning part of small intestine
Receives chyme from stomach
Digestive accessory structure
Pancreatic duct from pancreas
What is an accessory structure?
Organs that connect to digestive system and contribute to digestive process
What is pancreatic juice?
From pancreas goes into duodenum
Contains:
- bicarbonate
- lipase
- trypsin
- pancreatic amylase
What does bicarbonate do?
Neutralizes acid
What does lipase do?
Breaks down fat
Can only attack the surface of fat cells
Not effective
What is trypsin?
Protein digester
Releases amino acids
Works in different pH
What is pancreatic amylase?
Released for breakdown of starch
What does the pancreas do?
Exocrine and endocrine
Endocrine- secrets hormones directly into blood
What is another accessory structure?
Liver
What does the liver do?
Has bile ducts
Makes bile
Gall bladder stored bile
What are bile ducts?
Ducts connecting liver to duodenum
What is in bile?
Bile salts
What are bile salts?
Help lipase break down fats
One side is hydrophilic and other side hydrophobic
Hydrophobic part loves lipids and start breaking down big fat cell into smaller particles so lipase can break it down
What does emulsify mean?
Break down
What is the small intestine?
Primary place to absorb nutrients into your blood
More surface area better for absorption
Extremely long
Complex folding
Have villi
What are villi?
Finger like structures projecting out and increase surface area
Have microuilli
Arteries become what and then what?
Arteries—-> Arterioles (smaller vessels)——> capillaries (microscopic)
Found in small intestine
Veins become what?
Venules
Found in small intestine
Monosaccharides especially glucose is brought where? (In small intestine)
Into the blood
Fatty acids cannot be carried into the blood because? (In small intestine)
Hydrophobic
Carried in lymphatic system
Small things enter the blood through what…?
Large things like fatty acids enter the blood through what…?
Capillaries
Lymphatic system
What is the hepatic portal system?
Specialized system of veins
What does hepatic mean?
Liver
What are the standard order of veins?
Capillaries—-> venules——> veins——> heart
What is the portal system order of veins?
Capillaries—-> venules—-> veins—-> venules——> capillaries
What is a capillary bed?
System of veins that have capillaries on both sides
Picks up something from one bed
Let’s something go from other bed
What does the capillary in the intestines pick up?
What does the capillary in the liver absorb?
Chyme
Toxins
What does the liver store?
Store glycogen
Glycogen- polysaccharide
What are the 2 kinds of contractions in the small intestine?
1) peristalsis
2) segmentation
What is segmentation?
Simultaneous construction in small intestine at different places
To keep chyme mixed up periodically to get fresh chyme against the wall for absorption
What does the pressure difference do?
Move material from small to large intestine
What is the cecum?
Vastigle structure
Had vermiform appendix- the reduced tip of the cecum
What is appendicitis?
Appendix becomes inflamed and dumps fecal matter in abdominal cavity
What is the large intestine or colon?
Removes water out of chyme and end up with feces or fecal waste
What are the bile pigments?
Orange/ yellow in color
Make feces a certain color
What is the rectum?
Tube of anus
Last part of the tube
Anal sphincter- outer is skeletal muscle
Inner is smooth muscle
What is the anus?
Butthole
What does elimination mean?
Removal of digested material
What is the enteric nervous system?
Subdivision of autonomic nervous system
Build into digestive system
Capable of operating on its own
Parasympathetic and sympathetic connections
Brain of the gut
Controls digestive system
