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245 Cards in this Set
- Front
- Back
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What is ingestion?
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Ingestion is the acquirement of food (placing food into your mouth).
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What is digestion?
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Digestion is the chemical and mechanical degradation of the food into nutrients that the body can absorb.
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What is absorption?
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Absorption occurs when the nutrients cross the epithelial layer and enter the cells and blood.
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What chemical reaction can break down fats, proteins, carbohydrates, and nucleic acids?
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Hydrolysis.
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Name the basic anatomical features of the digestive tract, starting from the mouth and working your way along the alimentary tract.
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Mouth, esophagus, stomach, small intestine (consisting of the duodenum, jejunum, and illeum), large intestine (consisting of the ascending colon, transverse colon, descending colon, and sigmoid colon), rectum, anus.
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What organs dispel chemicals into the duodenum via the pancreatic duct?
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The pancreas, liver, and gall bladder.
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Where does physical digestion begin?
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In the mouth (chewing).
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Where does chemical digestion begin?
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In the mouth, via the enzyme amylase.
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What does the enzyme amylase do?
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Amylase digests carbohydrates.
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What is physical digestion?
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The breakdown of food via reactions which don't break intramolecular or covalent bonds.
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What is a bolus?
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The bolus is the chewed food, moistened and rolled into a ball.
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What type of act is swallowing?
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Swallowing is a partially voluntary and partially involuntary act.
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Once the food is chewed, what does the tongue do?
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The tongue assists in making and swallowing the bolus.
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What covers the windpipe?
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The epiglottis, which is a small cartilaginous member.
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How does the bolus move into the stomach?
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The epiglottis covers the windpipe, the tongue pushes the bolus over the epiglottis and into the esophagus, peristaltic action in the esophagus moves the bolus into the stomach.
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What digestive enzymes does the esophagus release?
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The esophagus releases no digestive enzymes dumbass.
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What is the most important job of the stomach?
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The most important job of the stomach is to store food.
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Why is it important for the stomach to store food?
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It allows you to take in a lot of food and then go do something else while it releases little bits at a time into your intestines. If you didn't have a stomach, you'd have to eat far more often.
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How does the stomach physically digest the food?
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The stomach physically digests the food by squeezing it back and forth from one side to another.
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How does the stomach chemically digest the food?
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The pH in the stomach is very low; it denatures proteins.
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What does the enzyme pepsin do?
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The enzyme pepsin works on the midsections of exposed peptide chains.
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What are the four important cell types in the stomach?
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mucous cells, parietal cells, G cells, and chief cells
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What do mucous cells do?
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Mucous cells secrete a viscous, alkaline mucous to protect the stomach epithelium from the highly acidic environment of the lumen, and also from physical abrasion of food particles.
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What do parietal cells do?
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Parietal cells release HCl into the lumen of the stomach.
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What do G cells do?
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G cells release gastrin into the capillaries surrounding the stomach.
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What is gastrin and what does it do?
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Gastrin is a peptide hormone which stimulates parietal cells to secrete acid.
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What do chief cells do?
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Chief cells secrete pepsinogen.
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How is pepsinogen activated?
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Pepsinogen is activated by HCl, especially in the presence of previously-activated pepsin.
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What is the optimal pH for pepsin?
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~pH 2
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What does the stomach ultimately reduce food to?
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The stomach reduces food to a semi-fluid mass called chyme.
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What is the interior surface of the small intestines made up of?
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The interior surface of the small intestine is made up of millions of tiny, finger-like projections called villi.
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What is on the surface of each villus?
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The surface of each villus consists of many epithelial cells called enterocytes.
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What does apical mean?
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Apical means the side facing the lumen.
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What does the apical surface of each enterocyte contain?
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The apical surface of each enterocyte contains many microvilli.
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What is the function of the villi and microvilli?
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The function of the villi and microvilli is to increase the surface area of the small intestines.
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How do microvilli appear under a light microscope?
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Microvilli appear as a fuzzy surface under a light microscope; this surface is called the brush border.
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What does the brush border contain?
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The brush border contains numerous digestive enzymes.
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When the chyme is released from the stomach, what is the nature of the pH?
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The pH is pretty low when the chyme is released from the stomach.
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How is the solution in the small intestine buffered against the low pH of the incoming chyme?
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The pancreas secretes bicarbonate ion via the pancreatic duct to buffer the solution in the small intestine at ~pH 6.
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What other enzymes does the pancreas secrete?
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The pancreas also secretes the enzymes trypsin, chymotrypsin, amylase, lipase, and some nucleases.
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In what state are the pancreatic enzymes released?
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All these enzymes are released as zymogens.
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How is trypsinogen activated to trypsin?
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Trypsinogen is activated to trypsin by a brush border enzyme called enterokinase.
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What enzyme, released by the pancreas, activates the other pancreatic enzymes?
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Activated trypsin activates the others.
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What do trypsin and chymotrypsin do?
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Trypsin and chymotrypsin work on the middle of peptide chains to make small peptides-this is why they're called endopeptidases.
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What does amylase do?
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Amylase breaks down carbohydrates to disaccharides and trisaccharides.
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What does lipase do?
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Lipase breaks down lipids, especially triglycerides.
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What do nucleases do?
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Nucleases break down nucleic acids.
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In the absence of bile, why does lipase have a hard time breaking down lipids in the duodenum?
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Since it is an aqueous solution in the duodenum, the fat tends to coagulate, reducing the surface area exposed to lipase.
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What organs secrete bile?
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Bile is secreted by the liver and gall bladder.
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What type of process is emulsification?
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Emulsification is a physical process which separates the fat molecules, but doesn't break them down chemically.
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What organ(s) do/does mainly digestion?
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The duodenum does mainly digestion.
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What organ(s) do/does mainly absorption?
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The jejunum and illeum do most of the absorption.
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What is the major role of the large intestine/colon?
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The major role of the large intestine/colon is to absorb water (this is why diarrhea is a symptom of problems in the large intestine).
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What do bacteria such as E. coli in the large intestine provide humans in their mutualistic relationship?
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Bacteria provide humans with vitamins K, B12, thiamin, and riboflavin.
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What three local peptide hormones are secreted by the small intestine following a meal?
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Secretin, cholecystokinin, and gastric inhibitory peptide.
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What do the local peptide hormones secretin, cholecystokinin, and gastric inhibitory peptide do?
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These hormones increase blood insulin levels, especially in the presence of glucose.
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What causes secretin release?
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HCl in the duodenum causes secretin release.
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What does secretin do?
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Secretin stimulates sodium bicarbonate secretion by the pancreas.
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What causes cholecystokinin release?
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Food in the upper duodenum, especially fat digestates, cause the release of cholecystokinin.
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What does cholecystokinin do?
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Cholecystokinin causes gall bladder contraction and pancreatic enzyme secretion.
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What else does cholecystokinin do?
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Cholecystokinin also decreases the mobility of the stomach, allowing the duodenum more time to digest fat.
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What does gastric inhibitory peptide do?
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Gastric inhibitory peptide has a mild effect in decreasing the motor activity of the stomach.
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What causes the release of gastric inhibitory peptide?
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Gastric inhibitory peptide is released in response to fat and protein digestates in the duodenum, and to a lesser extent, in response to carbohydrates.
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What is the "goal" of digestion?
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The goal of digestion is to break down food into the basic nutrients.
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What are the most basic nutrients?
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The most basic nutrients are monosaccharides, amino acids, and fatty acids.
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Why must the body break down food into basic nutrients?
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Only if food is broken down into it's basic nutrients can it be absorbed (the body doesn't absorb polysaccharides, polypeptides, or triglycerides).
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Where are nutrients absorbed?
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Nutrients are absorbed into the enterocytes of the small intestines, mainly in the duodenum.
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What are enterocytes?
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Enterocytes are epithelial cells lining the intestine.
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What forms can polysaccharides take?
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Polysaccharides could be glycogen, starch, cellulose, and chitin.
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What are two common disaccharides?
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Sucrose and lactose.
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Pertaining to food, where is glycogen found?
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Glycogen is found in animal cells like meat and fish.
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Pertaining to food, where are starch and cellulose found?
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Starch and cellulose are found in plant cells.
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Where is chitin found?
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Chitin is found in the exoskeletons of insects and also in mushrooms.
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What polysaccharides can't animals digest?
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Animals can't digest cellulose or chitin.
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Where does the disaccharide sucrose come from?
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The disaccharide sucrose is beet or cane sugar.
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What monosaccharides compose sucrose?
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Glucose and fructose.
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What monosaccharides compose lactose?
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Glucose and galactose.
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What percentage of the carbohydrates in a typical diet are broken down into glucose?
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80% of the carbohydrates in a typical diet are broken down into glucose.
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What percentage of the monosaccharides in the blood are glucose?
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95% of the monosaccharides in the blood are glucose.
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Where does carbohydrate digestion begin?
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Carbohydrate digestion begins in the mouth with salivary amylase and continues in the duodenum with pancreatic amylase.
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Since enterocytes don't absorb di- or trisaccharides, how are these carbohydrates broken down further?
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Enzymes in the brush border break down the di- and trisaccharides to monosaccharides.
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How are glucose and galactose absorbed?
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Glucose and galactose are absorbed via a secondary active transport mechanism, down the concentration gradient of sodium.
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How is fructose absorbed?
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Fructose is absorbed via facilitated diffusion, so it can't be taken in against it's concentration gradient (not as efficient).
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How does the cell deal with "the fructose problem"?
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Enzymes inside the enterocyte begin converting fructose to glucose.
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How are glucose, galactose, and fructose moved out of the cell?
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Glucose, galactose, and fructose move out of the enterocyte, across the basolateral surface of the cell via facilitated diffusion, and are absorbed into the blood.
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Where do the capillaries around the intestine drain to?
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The capillaries around the intestine drain into the hepatic portal vein, which leads to the liver.
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What does the liver do with the monosaccharides?
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The liver continues to convert fructose and galactose to glucose, storing much of the glucose as glycogen.
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Where does digestion of proteins begin?
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Digestion of proteins begins in the stomach.
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How are proteins digested in the stomach?
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HCl denatures the proteins and pepsin begins attacking the middle of the polypeptide chains.
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Does protein absorption occur in the stomach?
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No.
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The protein digestates that enter the duodenum are....
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The protein digestates that enter the duodenum are polypeptide chains.
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What breaks down polypeptides into di- and tripeptides in the duodenum?
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Trypsin and chymotrypsin from the pancreas break down these polypeptides into di- and tripeptides.
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How are small polypeptides reduced to amino acids?
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Small polypeptides reach the brush border, where they are reduced to amino acids by brush border enzymes.
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For carbohydrate and protein digestion, ... are broken down into small pieces by the ... enzymes, but it is the enzymes of the brush border that complete the breakdown to basic nutrients.
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For carbohydrate and protein digestion, MACROMOLECULES are broken down into small pieces by the PANCREATIC enzymes, but it is the enzymes of the brush border that complete the breakdown to the basic nutrients.
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How do the enterocytes absorb amino acids and a few di- and tripeptides?
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The enterocyte absorbs amino acids and a few di- and tripeptides via secondary active transport down the concentration gradient of sodium, or, in the case of a few amino acids, via facilitated diffusion.
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The variety of amino acids require a variety of transport proteins and mechanisms. Why don't any di- or tripeptides reach the blood?
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No di- or tripeptides reach the blood because enzymes in the enterocyte break them down to amino acids before releasing them out the basolateral side of the cell and into the blood.
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What does most of dietary fat consist of?
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Most of dietary fat consists of triglycerides.
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What does emulsify mean?
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Emulsify = separate fat into small globules without breaking molecular bonds.
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What does lipase do to triglycerides?
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Lipase breaks triglycerides into monoglycerides and fatty acids.
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What shuttles the fat digestates to the brush border?
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Bile micelles shuttle the fat digestates to the brush border.
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How do fat digestates enter enterocytes?
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The fat digestates diffuse through the phospholipid bilayer of the enterocytes.
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Once inside the enterocyte, what happens to the fatty acids and monoglycerides?
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Once inside the enterocyte, the fatty acids and monoglycerides are turned back into triglycerides at the SER.
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What aggregates to form chylomicrons?
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Fat digestates, which have been turned back into triglycerides at the SER, along with cholesterol and phospholipids, aggregate to form chylomicrons.
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How are chylomicrons released out the basolateral surface of the enterocyte?
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Chylomicrons are released out the basolateral surface of the cell via exocytosis.
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Chylomicrons go into the lacteals instead of the blood. The lymph system then carries the chylomicrons to....
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The lymph system carries the chylomicrons to the thoracic duct, where they are emptied into the jugular vein in the neck.
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Once in the blood, where do most of the chylomicrons carry their digestates?
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Once in the blood, most of the chylomicrons carry their digestates to the liver, while some go directly to adipose tissue.
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What is the major role of the liver?
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The major role of the liver is to regulate the glucose concentration in the blood.
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Why must the glucose concentration remain fairly constant?
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The glucose concentration must remain fairly constant because most cells take in glucose by facilitated diffusion; if the glucose concentration of the blood were to fall below the glucose concentration of the cell, glucose would actually diffuse out of the cell.
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Where does the liver receive blood from?
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The liver receives blood directly from the intestines via the hepatic portal vein and also has a second blood supply via the hepatic artery from which it receives oxygen-rich blood.
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After a meal, the blood from the hepatic portal vein is.....
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After a meal, the blood from the hepatic portal vein is RICH IN NUTRIENTS.
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How do fat digestates enter enterocytes?
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The fat digestates diffuse through the phospholipid bilayer of the enterocytes.
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Once inside the enterocyte, what happens to the fatty acids and monoglycerides?
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Once inside the enterocyte, the fatty acids and monoglycerides are turned back into triglycerides at the SER.
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What aggregates to form chylomicrons?
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Fat digestates, which have been turned back into triglycerides at the SER, along with cholesterol and phospholipids, aggregate to form chylomicrons.
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How are chylomicrons released out the basolateral surface of the enterocyte?
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Chylomicrons are released out the basolateral surface of the cell via exocytosis.
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Chylomicrons go into the lacteals instead of the blood. The lymph system then carries the chylomicrons to....
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The lymph system carries the chylomicrons to the thoracic duct, where they are emptied into the jugular vein in the neck.
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Once in the blood, where do most of the chylomicrons carry their digestates?
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Once in the blood, most of the chylomicrons carry their digestates to the liver, while some go directly to adipose tissue.
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What is the major role of the liver?
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The major role of the liver is to regulate the glucose concentration in the blood.
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Why must the glucose concentration remain fairly constant?
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The glucose concentration must remain fairly constant because most cells take in glucose by facilitated diffusion; if the glucose concentration of the blood were to fall below the glucose concentration of the cell, glucose would actually diffuse out of the cell.
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Where does the liver receive blood from?
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The liver receives blood directly from the intestines via the hepatic portal vein and also has a second blood supply via the hepatic artery from which it receives oxygen-rich blood.
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After a meal, the blood from the hepatic portal vein is.....
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After a meal, the blood from the hepatic portal vein is RICH IN NUTRIENTS.
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Rather than capillaries, what does the liver have?
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The liver has sinusoids, which are flat sacks with increased surface area to facilitate gas and nutrient exchange.
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Besides gas/nutrient exchange, what can the sinusoids do?
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The sinusoids can expand and act as a blood storage reservoir for the body.
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The liver has Kupfer cells. WTF are Kupfer cells?
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Kupfer cells are specialized macrophages capable of phagocytizing bacteria that have entered the blood from the digestive tract. Kupfer cells can also destroy irregular RBCs.
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What does the liver metabolize?
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The liver metabolizes carbohydrates, fats, and proteins.
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What else does carbohydrate metabolism include?
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Carbohydrate metabolism includes gluconeogenesis.
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What is gluconeogenesis?
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Gluconeogenesis is the formation of glucose and glycogen from non-carbohydrate precursors.
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What does fat metabolism by the liver include?
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Fat metabolism by the liver includes synthesizing bile from cholesterol and converting excess carbohydrates and proteins into fat.
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What organ makes most of the body's lipoproteins?
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The liver makes most of the body's lipoproteins.
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What organ detoxifies chemicals?
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The liver detoxifies chemicals.
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What are the seven important functions performed by the liver? Don't F this up.
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Blood storage, blood filtration, erythrocyte destruction, carbohydrate metabolism, protein metabolism, fat metabolism, and detoxification. Good job asshat!
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What are the three functions of the kidney?
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Excretion of waste products, homeostasis of the body fluid volume and solute composition, and control of plasma pH. You better have gotten this one right, tool.
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What is homeostasis?
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Homeostasis is the maintenance of a constant internal environment.
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How big is a kidney?
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The kidney is about the size of a fist.
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The two main parts of the kidney are...
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The two main parts of the kidney are the cortex (bark) and medulla (middle).
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Where is urine created?
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Urine is created by the kidney in the medulla and emptied into the renal pelvis. Unless you got this wrong; then I'd say that urine is created by functionless mass you call a brain.
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Where does the renal pelvis drain?
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The renal pelvis drains into the ureter.
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What is the ureter?
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The ureter is a tubular vessel that carries the urine to the bladder.
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What is the function of the bladder?
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The bladder stores the urine until it can be "conveniently" drained out of the urethra.
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What is the functional unit of the kidney?
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The functional unit of the kidney is the nephron.
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The nephron that we're considering is the juxtamedullary nephron, so where is it?
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The juxtamedullary nephron is in the cortex, next to the medulla.
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What would be considered waste products of the kidney?
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Urea, ammonia, uric acid, and phosphate.
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What portion of the nephron dips into the medulla?
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The loop of Henle dips into the medulla.
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What does the renal corpuscle consist of?
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The renal corpuscle consists of the glomerulus and Bowman's capsule.
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What is the glomerulus?
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The glomerulus is a capillary bed: blood flows into the glomerulus and is filtered by tiny fenestrations leading into Bowman's capsule.
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How big are the glomerular fenestrations?
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The fenestrations are the size of medium-sized proteins, far too small for cells to fit through, but the aqueous solution of the blood and many things in it can fit through.
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What are factors in determining whether something can pass through glomerular fenestrations?
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Charge and size.
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What flows freely through glomerular fenestrations?
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Water, glucose, amino acids, and ions flow freely through the fenestrations.
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Albumin, a medium-sized, osmoregulatory protein, is about the size of a fenestration, but isn't filtered. Why?
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Albumin's polarity and charges prevent it from being filtered.
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What is the solution that forms in Bowman's capsule called?
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The resulting solution that forms in Bowman's capsule is called filtrate or pre-urine.
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What plays a major role in the amount of filtrate produced?
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Glomerular blood pressure plays a major role in the amount of filtrate produced by pushing the fluid into Bowman's capsule.
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Besides glomerular BP, what also affects filtration rate?
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Osmotic pressure also affects filtration rate.
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From Bowman's capsule, where does the filtrate move to?
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From Bowman's capsule, the filtrate moves to the proximal convoluted tubule.
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What happens at the proximal tubule?
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The proximal tubule is where most of the reabsorption and secretion takes place.
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What does "reabsorption" mean?
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Reabsorption means that the epithelial cells of the tubule absorb the solute from the filtrate.
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What does "secretion" mean?
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Secretion means that the epithelial cells secrete the solute into the filtrate.
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What solutes are reabsorbed in the proximal tubule?
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Solutes that are reabsorbed in the proximal tubule are the things that we don't want to waste: glucose, amino acids, and proteins.
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How are glucose and many amino acids reabsorbed in the proximal tubule?
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Like the enterocytes in the intestines, glucose and many amino acids are reabsorbed utilizing a sodium co-transport protein that carries glucose or amino acids into the cell along the concentration gradient of sodium.
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In the proximal tubule, why aren't all amino acids removed from the filtrate?
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Some amino acids are reabsorbed via facilitated diffusion, so not all of them can be reabsorbed.
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How are proteins reabsorbed?
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Proteins are reabsorbed via pinocytosis, which is considered active transport because it requires energy.
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After the proximal tubule, where does the fluid flow?
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The fluid flows into the loop of Henle.
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What are the three parts to the loop of Henle?
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Thin descending limb, thin ascending limb, thick ascending limb
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What is the thin descending limb in the loop of Henle permeable to?
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The thin descending limb is permeable to water but only moderately permeable to solutes.
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What happens to the water in the filtrate as the loop of Henle descends into the concentrated medulla?
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Water passively diffuses out of the filtrate as the loop of Henle descends into the concentrated medulla.
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What are the thick and thin ascending limbs impermeable to?
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The thick and thin ascending limbs are impermeable to water.
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What does the thick ascending limb do?
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The thick ascending limb actively reabsorbs solute.
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What happens to the filtrate concentration in the loop of Henle?
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The filtrate becomes more concentrated as it goes down one side of the loop of Henle, but becomes more dilute as it goes up the other side.
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Where does the loop of Henle concentrate solute?
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The loop of Henle concentrates solute in the medulla, not in the filtrate-this prepares the kidney to produce concentrated urine.
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What does the early distal tubule do?
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The early distal tubule dilutes the filtrate still more.
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What two hormones act on the distal tubule?
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Both ADH and aldosterone act on the distal tubule. In addition, ADH acts on the collecting ducts.
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What effect does aldosterone have in the distal tubule?
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Aldosterone causes the secretion of potassium (K) and the reabsorption of sodium (Na).
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What effect does ADH have in the distal tubule?
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ADH causes the absorption of water.
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What does the distal tubule drain into?
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The distal tubule drains into the collecting ducts.
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What hormone acts strongly in the collecting duct?
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ADH acts strongly in the collecting duct.
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The collecting duct dives deep into the medulla, which has been ....
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The collecting duct dives deep into the medulla, which has been CONCENTRATED BY THE LOOP OF HENLE.
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Anti-Diuretic Hormone (ADH), now referred to as Always Digging Holes. Why?
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Because ADH digs holes in the collecting duct, so that water may passively diffuse out of it.
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Since the ... is concentrated, water leaves the ... and moves into the medulla, causing the ... to become concentrated.
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Since the MEDULLA is concentrated, water leaves the FILTRATE and moves into the medulla, causing the URINE to become concentrated.
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The urine is concentrated in the collecting duct (in the presence of ADH), but in order to concentrate the urine, you need....
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A loop of Henle to concentrate the medulla.
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What are the vasa recta?
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The vasa recta are capillary beds around the loops of Henle.
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Describe the blood flow of the vasa recta.
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The blood flow of the vasa recta is in the opposite direction of the filtrate flow and allows for the maintenance of the concentration of the medulla.
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What does the juxtaglomerular apparatus do?
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The juxtaglomerular apparatus helps to control the glomerular filtration rate by changing renal arterial resistance (the juxtaglomerular apparatus controls the blood pressure in the glomerulus and thus the amount of filtrate).
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What do macula densa cells in the distal tubule do?
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Macula densa cells in the distal tubule monitor filtrate volume and sodium concentration.
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When filtrate volume is low, what do the macula densa cells do?
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When filtrate volume is low, the macula densa release a signal, probably a hormone, that lowers the resistance to the efferent arterioles of the glomerulus. This increases the hydrostatic pressure in the glomerulus, causing the filtrate rate to increase.
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What is renin?
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Renin is an enzyme that cleaves angiotensinogen to angiotensin-1, which is converted to angiotensin-2, which constricts the efferent arterioles, further increasing the glomerular pressure and filtration rate.
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What does angiotensin-2 also do?
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Angiotensin-2 also stimulates the release of aldosterone, which causes increased reabsorption of sodium in the distal tubule.
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When filtrate volume is low, there is more time to reabsorb sodium, so....
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Sodium concentration of the distal tubule decreases. In response, renin is released into the blood from the juxtaglomerular cells.
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In a nutshell, what does the juxtaglomerular apparatus do?
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The juxtaglomerular apparatus increases the glomerular filtration rate, when needed, and helps to conserve sodium, when needed. It does this via a cascade of renin, angiotensin-1, angiotensin-2, and aldosterone.
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What is the major osmoregulatory protein in the blood?
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Albumin is the major osmoregulatory protein in the blood.
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Name two important clotting factors.
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Prothrombin and fibrinogen.
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Globulins are a group of proteins that include antibodies; what makes antibodies?
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Antibodies are made by plasma cells.
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What are the eight interrelated functions of the liver?
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Blood storage, blood filtration, erythrocyte destruction, carbohydrate metabolism, protein metabolism, fat metabolism, detoxification, and vitamin storage.
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What vitamins does the liver store?
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The liver stores vitamins A, D, and B12. The liver also stores iron, combining it with the protein apoferritin to form ferritin.
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What cells of the liver filter blood?
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The Kupfer cells of the liver phagocytize bacteria picked up from the intestines.
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Briefly describe fat metabolism in the liver.
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The liver synthesizes bile from cholesterol and converts carbohydrates and proteins into fat. It oxidizes fatty acids for energy, and forms most lipoproteins.
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What cells in the liver are responsible for erythrocyte destruction?
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Kupfer cells destroy irregular erythrocytes, but most irregular erythrocytes are destroyed by the spleen.
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When the liver mobilizes fat for energy, what does it produce?
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When the liver mobilizes fat for energy, it produces acids called ketone bodies.
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What condition does the production of ketone bodies often result in?
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The production of ketone bodies often results in ketosis or acidosis.
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When the liver mobilizes fat or protein for energy, what happens to the acidity of the blood?
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The blood acidity increases (pH drops).
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Where does gluconeogenesis mainly take place.
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Gluconeogenesis occurs mainly in the liver.
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Where does fat storage take place?
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Fat storage takes place in adipocytes.
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How do most fat digestates enter the lymph?
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Most fat digestates enter the lymph as chylomicrons via lacteals.
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Where are triglycerides synthesized?
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Smooth endoplasmic reticulum synthesizes triglycerides.
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What is vasopressin?
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Vasopressin is an antidiuretic hormone which increases water retention.
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Each kidney is a fist-sized organ made up of an outer ______ and an inner _______.
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Each kidney is a fist-sized organ made up of an outer CORTEX and an inner MEDULLA.
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Urine is created by the _____ and emptied into the _________
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Urine is created by the KIDNEY and emptied into the RENAL PELVIS.
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The renal pelvis is emptied by the _______, which carries urine to the ______.
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The renal pelvis is emptied by the URETER, which carries urine to the BLADDER.
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The bladder is drained by the _____.
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The bladder is drained by the URETHRA.
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Where does filtration occur in the kidney?
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Filtration occurs in the renal corpuscle.
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Where do reabsorption and secretion occur in the kidney?
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Reabsorption and secretion occur mostly in the proximal tubule.
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What part of the kidney concentrates solute in the medulla?
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The loop of Henle concentrates solute in the medulla.
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Where does the distal tubule empty?
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The distal tubule empties into the collecting duct.
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What does the collecting duct of the kidney do?
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The collecting duct concentrates the urine.
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When the blood glucose level decreases, what process occurs in the liver that returns glucose to the blood?
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Glycogenolysis.
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When glycogen stores are full, what is glucose converted to?
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When glycogen stores are full, glucose is converted to fat.
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Where are most lipoproteins made?
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Most lipoproteins are made in the liver.
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What transports triglycerides from the liver to the adipose tissue?
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Very-low density lipoproteins transport triglycerides from the liver to the adipose tissue.
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What are the derivatives of the ectoderm?
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central and peripheral nervous systems; epidermis, hair, and nails of the skin; lens of the eye
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What are the derivatives of the endoderm?
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epithelial lining of all the major lumenal surfaces (GI and resp. tracts); liver, pancreas, gall bladder, accessory GI organs
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What are the derivatives of the mesoderm?
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cardiovascular system; muscular system; skeletal system; excretory system
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In fetal circulation, blood coming through the umbilical vein is shunted around the liver through...
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ductus venosus
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Upon birth, the ductus venosus closes off, and the adult remnant is called the...
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ligamentum venosum
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In an embryo, blood is shunted around the lungs two ways:
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the foramen ovale allows blood to flow from the right atrium into the left atrium, bypassing the ventricles; later in the circulation, the ductus arteriosus shunts blood from the pulmonary artery (coming out of the right ventricle) directly into the aorta
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Where is testosterone made and what does it do?
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Testosterone is made by the testes and is necessary for genital development and secondary sexual charateristics.
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Where is prolactin made and what does it do?
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Prolactin is the product of the anterior pituitary and stimulates breast milk synthesis.
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What produces epinephrine, which does what?
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Epinephrine is produced by the adrenal medulla to stimulate the "fight or flight" response in conjunction with the sympathetic nervous system
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What is the main function of the hypothalamus?
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maintain homeostasis-holding such factors as BP, body temp, fluid and electrolyte balance, and body weight at a precise "set-point"
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What is the medulla oblongata?
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a swollen upper tip of the spinal cord containing the breathing centers that control the rate of breathing by controlling the diaphragm
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What does the cerebellum do?
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coordinates balance and body movements during walking, running, etc-damage to the cerebellum results in jerky and uncoordinated movements
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What does erythropoietin do?
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activates the bone marrow to produce RBCs
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What does renin do?
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stimulates the adrenal gland to release aldosterone
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The autonomic nervous system is divided into two divisions; what are they?
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sympathetic and parasympathetic
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What does the parasympathetic system rely on as its main neurotransmitter?
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acetylcholine (ACh)
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As a whole, what does the parasympathetic system do?
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functions to "rest and digest"; promotes energy conservation by reducing the HR and BP, and facilitates digestion by stimulating the digestive tract and all accessory organs (like the pancreas)
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As a whole, what does the sympathetic system do?
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used during periods of "fight or flight"; causes an increase in BP and a decrease in GI function
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What is the neurotransmitter used by the sympathetic nervous system?
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norepinephrine
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What is the anatomy of the excretory system starting from the urethra and moving into the body?
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opening to the urethra, urethra, bladder, opening to the ureter, ureter, kidney renal pelvis
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Renal gross anatomy
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kidney, ureter, bladder, urethra
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Anatomy of the male reproductive system starting from the urethra and moving into the body
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opening to the urethra, urethra, prostate, ejaculatory duct, vas deferens, epididymis, seminiferous tubules
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What are the biological effects of epinephrine?
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epinephrine mediates a sympathetic nervous system "fight or flight" response; the biological effects include: increased BP, increased HR, pupil dilation, inhibition of GI system
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What is the digestive tract lined with?
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The digestive tract is lined with involuntary smooth muscle that is controlled by the autonomic nervous system.
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What does ADH act on?
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ADH acts on receptors of the collecting tubule or duct, to allow them to reabsorb more water. These cells are impermeable to water in the absence of ADH
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What does gastrin do?
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Gastrin stimulates the stomach to release HCl.
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What is intrinsic factor needed for?
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Intrinsic factor is needed for the absorption of vitamin B12.
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What two hormones regulate body volume and where are they made?
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ADH and aldosterone; ADH is made in the hypothalamus and stored in the posterior pituitary, aldosterone, stimulated by angiotensin II, is made in the adrenal cortex.
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What does dehydration cause?
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Dehydration causes both the release of renin from the kidneys and the stimulation of osmoreceptors in the hypothalamus
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What are the effects of ADH and aldosterone on the body?
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Together, the effects of ADH and aldosterone result in an increase of body fluids and an increase in BP
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