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Review Questions For 3rd Midterm
Gastrointestinal Physiology
The kidney’s many functions include:
1. Elimination of soluble wastes (including nitrogen from proteins, which is eliminated in the form of _______________)
2. Maintenance of water and ___________ balance
3. Maintenance of acid/base balance by eliminating (name the molecules!) __________ and reabsorbing _________
Label the nephon and kidney below with the following labels (they’re not to scale):
Ascending Loop of Henle
Proximal Convoluted Tubule
Descending Loop of Henle
Distal Convoluted Tubule
Collecting Tubule
Glomerulus
Afferent Arteriole
Bowman’s Capsule
Efferent Arteriole
Podocytes
Urethra
Ureter
Bladder
Vasa Recta
Kidney
What parts of the nephron are in the cortex of the kidney, and what part is in the medulla? Label the drawing to orient you to cortex and medulla.
Review Questions For 3rd Midterm
Gastrointestinal Physiology
The 3 processes involved in urine formation are ________________ at the glomerulus and ________________ and ________________which happen along the tubules.
Calculating GFR
GFR stands for ________________________________, which is a measure of how much fluid leaves the glomerular capillaries and enters the nephron per minute.
______________is a synthetic carbohydrate that is used to calculate GFR. This carbohydrate is used because all the molecules that enter the glomerulus at the afferent
arteriole leave in the urine without being added into the tubule or taken out of the tubule. In other
words, it is freely ___________________ and not __________________ or __________________.
Using the concentrations of this molecule in the blood and urine, and the urine flow, an equation may be set up to calculate GFR. What is that equation?
Most healthy people have an average GFR = _________ml/min.
GFR changes
How would the following things affect GFR? (increase/decrease/stay the same)
Constricting the afferent arteriole:
Constricting the efferent arteriole:
A significant decrease in plasma proteins:
Very low blood pressure:
Clearance vs. GFR
Suppose you invent a new drug and you want to see how it is affected by the kidney. You can do an experiment to compare the clearance of the drug with the GFR.
This will tell you whether the drug is manipulated in the nephron by reabsorption or secretion.
Clearance > GFR means that (more/less) drug is in the urine than just what is filtered at the glomerulus, and the drug must be (reabsorbed / secreted).
Clearance < GFR means that (more/less) drug is in the urine than just what is filtered at the glomerulus and the drug must be (reabsorbed / secreted).
The Countercurrent Multiplier:
The descending Loop of Henle is permeable to __________but not to ____________
The ascending Loop of Henle is impermeable to _________ but pumps out ___________ using ATP powered pumps.
As filtrate moves through the descending LOH, it gets (diluted / concentrated) because of the (low / high) concentration of solute in the interstitial space around the
tubule.
Moving through the ascending LOH, it gets (diluted / concentrated).
The overall effect is reabsorption of ___________ and ____________ which concentrates the filtrate.
This mechanism causes a gradient of solutes from the cortex (approximately _________mosm/ml) to the medulla (approximately __________mosm/ml). This gradient
is due to both Na+ another molecule, _________, which is involved in a concentrating cycle mentioned in your lecture notes. This molecule, when found in high
concentration in the plasma, is a sign of renal failure.
Fill in the chart below about the three main hormones that regulate the kidney:
Hormone
Origin
posterior
pituitary
Trigger
Site of Action
Effect
Collecting tubule
Decrease Na+ reabsorption
Angiotensinogen is converted
to Angiotensin I.
Review Questions For 3rd Midterm
Gastrointestinal Physiology
Put the structures in the order in which your lunch might see them (it may help to draw):
Esophagus
Small intestine
Anus
Pharynx
Mouth
Stomach
Large intestine
Epiglottis
Appendix
Sphincter of oddi
Name the four main layers of the tissues in the digestive tract (from the inside out) and the main characteristics of each:
1.
2.
3.
4.
The stomach
The stomach has three regions: ______________, ________________, _______________
And three muscle layers: ________________, ________________, ________________
Two regions, the _______________ and the _______________ , contain deep narrow glands containing
1. acid-secreting _______________ cells
2. _________________ secreting chief cells
3. cells that secrete ____________.
The last region, the ______________ contains shallow wider glands _________________ secreting G cells.
The three phases of gastric motility are:
1.
______________________ : smell, taste, and thoughts of food
2.
______________________ : stretching and gastrin induced
3.
______________________ : duodenum stretching cause inhibitory nerve signals to stomach
hormones from the duodenum inhibit stomach
The three phases of gastric secretion are:
1.
Cephalic:________________________________________________
2.
Gastric: what is happening with G-cells and parietal cells in this stage?________________________________________________
3.
Intestinal: _______________________________________________
Two of the most widely used drugs in the world are used to inhibit the acid secreting cells in the stomach to treat “heartburn,” which is also known as GERD
(______________________________), and to treat gastric ulcers, which are associated with a bacteria called _______________________. The more recent drug,
Prilosec, is very effective because it actually inhibits the _____________ pumps in the parietal cells. An older group of drugs, H2 blockers, block parietal cell activation
by blocking __________________binding to H2 receptors.
Circle the things that are absorbed in the stomach:
Water
calcium
fat
alcohol
aspirin
Vitamin B12
The Pancreas
The pancreas is an exocrine gland, which secretes precursors of enzymes for digestion. The branching ducts end in grape-like clusters of _____________.
Review Questions For 3rd Midterm
Gastrointestinal Physiology
Fill in the following table for digestive enzymes/secretions:
Enzyme/Secretion
Source
Amylase
Salivary
Pancreatic
Function
HCl
HCO3Lipase
Trypsin
Enteropeptidase
Bile
Made in:
Stored in:
Nutrient Absorption:
The ________ intestine is the site of most absorption. It has circular folds, villi, and microvilli to maximize __________________________, which allows for more
contact of the intestinal cells with the nutrients inside the lumen.
The main function of the ________________ intestine is ________________ absorption. ____________________ here also help consume unabsorbed nutrients and
synthesize vitamin________.
Name the breakdown products of:
Carbohydrates:
Proteins:
Fats:
___________________is the coordinated waves of circular muscle contraction in the intestines.