Chapter 23 EXAM PORTION Flashcards
Define metabolism?
All chemical reactions in the body
What are the 3 main functions of digestiom?
Take in food, break it down into nutrient molecules, absorb molecules into the bloodstream
6 Step Process of digestion
- Ingestion
- Propulsion
- Mechanical breakdown
- Digestion
- Absorption
- Defecation
What is the difference between digestion and metabolism?
Digestion is breakdown of food in the GI tract whereas metabolism is all the chemical reactions in the entire body
What important functions do bile salts perform?
Lipid emulsification
What is the difference between long and short reflexive pathways?
Long is outside the GI tract and short is inside the GI tract
What are the organs of the digestive system?
Mouth, pharynx, esophagus, stomach, small intestine, large intestine, anus
What are the accessory organs of the digestive system?
Teeth, tongue, gallbladder, salivary glands, liver, pancreas
Where does carbohydrate breakdown begin and what does it break down into?
Starts in mouth and breaks down into galactose, glucose, fructose
Where does protein digestion start and what does it break down into?
Starts in stomach and breaks down into polypeptides, peptides and amino acids
Where does lipid digestion begin and where does major emulsification occur?
Starts in mouth and ME occurs in liver
What are the divisions of the small intestine in order?
Duodenum, jejunum, ileum
4 tunic layers in order
Mucosa, submucosa, muscularis externa, serosa
What are the 4 main parts of the urinary system in order from most superior organ?
Kidney, ureter, bladder, urethra
Describe location of the kidney using anatomical terminology
Retroperitoneal, between T12 and L5.
What structure reduces the spread of infection to the kidney?
Fibrous capsule
What is the flow of urine?
Renal pyramid, minor calyx, major calyx, renal pevlis, ureter
What is an important function of JGC
Regulate rate of filtrate formation and BP
What are the 3 JGC cells?
Macula densa, JG cells and extraglomerular mesangial cells
Glomerular filtration rate is directly proportional to?
Net filtration pressure, total surface area, filtration membrane permeability, intrinsic controls
What is different about the glomerulus vs other capillary systems?
It is drained by an efferent arteriole
What establishes the medullary osmotic gradient?
Mostly the permeability properties of the nephron loop.
List the salivary glands
Parotid, submandibular, sublingual.
What is the digestive function of the liver?
Production of bile.
What is the digestive function of the gallbladder?
Storage of bile.
What is the digestive function of the pancreas?
Supplies most of the enzymes needed to digest chyme as well as bicarbonate to neutralize stomach acid
What is the digestive function of the mouth?
Food is chewed and mixed with enzyme containing saliva that begins process of digestion and swallowing process is initiated
Digestive function of the pharynx
Food passes from the mouth into the oropharynx and then into the laryngopharynx
What is the digestive function of the esophagus?
Allows for the passage of material from the mouth and throat to the stomach
What is the digestive function of the stomach?
Termporary storage tank that starts chemical breakdown of protein digestion. Converts bolus of food to paste-like chyme, empty is 50mL volume but can expand to 4L.
What is the major digestive function of the large intestine?
Propulsion of feces to anus and defecation
What is the name of the GI tracts nervous system?
Enteric nervous system also called the gut brain. Contains more neurons than the spinal cord.
Parasympathetic system ____ digestive process
Enhances
Sympathetic system ____ digestion
Inhibits
What is the enteric nervous system made up of?
Enteric neurons that communicate extensively with eachother
What are the 3 types of mucosa layers?
Epithelium, lamina propria, muscularis mucosae
What are the 2 types of circulation for the digestive system?
Sphlanchnic circulation and hepatic portal circulation
What does sphlanchnic circulation include?
Arteries that branch off the aorta to serve digestive organs. (Hepatic, splenic, left gastric, inferior and superior mesenteric arteries)
What does hepatic portal circulation do?
Drains nutrient rich blood from digestive organs and delivers blood to liver for processing
What type of muscle is in the internal anal sphincter?
Smooth muscle
What type of muscle is in the external anal sphincter?
Skeletal muscle
What does the gastroesophageal sphincter surround and what is it’s purpose?
Cardial orifice and it keeps it closed when food is not being swallowed, mucus cells on each side protect esophagus from acid reflux
What is the purpose of the upper esophageal sphincter?
Allows food to enter esophagus
Where is the pyloric sphincter?
Bottom of the stomach
What is the purpose of the ileocecal sphincter?
Relax and admit chyme into large intestine - small intestine
What are the subdivisions of the large intestine?
- Cecum
- Appenxid
- Colon
- Rectum
- Anal canal
What is the cecum?
First part of the large intestine?
What is the appendix and what is it’s function?
Masses of lymphoid tissue. Part of MALT of immune system. Stores bacteria capable of recolonizing gut when necessary.
Why is the appendix susceptible to blockages?
Twisted shape
What are the 2 types of colon and where do they run?
Descending (down left side of abdominal cavity). Sigmoid (S-shaped portion that travels through pelvis)
What is peristalsis?
Major means of propulsion of food that involves alternating waves of contraction and relaxation
What is segmentation?
Local constriction of intestine that mixes food with digestive juices
What is haustral contractions?
Most contractions of colon, where haustra sequentially contract in response to distension.
What is the location and function of the parotid salivary gland?
Anterior to ear and external to masseter muscle. Parotid duct opens into oral vestibule next to second upper molar.
What is the location and function of the submandibular salivary gland?
Medial to body of mandible. Duct opens at base of lingual frenulum
What is the location and function of the sublingual salivary gland?
Anterior to submandibular gland under tongue. Opens via 10-12 ducts into floor of mouth
