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40 Cards in this Set
- Front
- Back
Anatomy of the digestive tract:
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1. mouth
2. esophagus 3. stomach 4. small intestines (duodenum, ileum, jejunum) 5. large intestines (ascending colon, transverse colon, descending colon, sigmoid colon) 6. rectum 7. anus |
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Alpha-amylase
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Contained in saliva
Begins the process of starch digestion. It takes starch chains and breaks them into smaller pieces with two or three glucose units |
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Peristaltic Action
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A wave motion performed by smooth muscle
It's similar to squeezing a tube of toothpaste at bottom and sliding fingers toward top to expel toothpaste |
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Chyme
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The semifluid, creamy material produced by digestion of food
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What are the four major cell types in the stomach?
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1. mucous cell
2. chief (peptic) cell 3. parietal (oxyntic cells) 4. G cell |
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Where does protein digestion begin?
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In the stomach
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What is the function of a mucous cell?
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-Contains rough ER and golgi to make mucus, composed of glycoprotein and electrolytes
-Lubricates the stomach wall so that food can slide along its surface without causing damage -Mucous protects the protect the cell wall from the stomachs acidic environment -Some secrete pepsinogen |
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Chief Cells
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Secrete pepsinogen, the precursor to pepsin
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How is Pepsinogen activated to pepsin?
What does this activation cause? |
It's activated to pepsin by a low pH in the stomach.
Once activated, pepsin begins digestion. |
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What is the function of parietal cells?
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Secrete hydrochloric acid (HCl) which goes from the original location of the parietal cells, in the exocrine glands, to the lumen of the stomach
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G cells
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Secrete gastrin into the interstitial fluid.
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Gastrin
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A large peptide hormone which is released from G cells
Gastrin is then absorbed into the blood and stimulates parietal cells to secrete HCl |
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Villi (sing, Villus)
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Tiny, finger-like projections that enable the small intestine to absorb nutrients from food.
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Lacteal
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The lymph vessel within a villus that absorbs nutrients which pass through the small intestine
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Brush Border
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A fuzzy covering of microvilli over villi which contain membrane bound digestive enzymes such as carbohydrates, proteins, nucleotides
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Goblet Cells
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Secrete mucus to lubricate intestines and help protect brush border from mechanical and chemical damage
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What are 6 major enzymes that are released by the pancreas?
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trypsin, chymotrypsin, pancreatic amylase, lipase, ribonuclease and deoxyribonuclease
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The purpose of Trypsin and Chymotrypsin in the small intestine?
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They degrade proteins into small polypeptides
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Where does 90% of digestion and absorption occur?
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In the small intestine
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Pancreatic amylase
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-Like salivary alpha-amylase, but more powerful
-Hydrolyzes polysaccharides to disaccharides and trisaccharides -Degrades carbohydrates of chyme to small glucose polymers |
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Lipase
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Degrades fat, specifically triglycerides
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Bile
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Produced by liver and stored in gall bladder
Bile breaks up fat into small particles without changing it chemically |
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Large intestine
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Help with water reabsorption and electrolyte absorption.
When there's a problem with the large intestine, diarrhea results |
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1. The body eats to gain ________ in the form of food.
2. The digestive system breaks down the food so it can be ___________ into the body. |
1. Energy
2. Absorbed |
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Zymogen
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The inactive precursor of an enzyme
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Hydrolysis
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The rupture of chemical bonds by the addition of water
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Urea
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The major end product of nitrogen metabolism in humans and mammals that is found in urine
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Nearly all _________ is converted to urea by the ________ and then excreted in the urine by the kidney.
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1. Ammonia
2. Liver |
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Albumin
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A type of protein which is water soluble
It helps move many small molecules through the blood |
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For the MCAT you should associate fat with two things:
1. 2. |
1. Efficient long-term energy storage
2. Lots of calories (energy) with little weight |
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Name the 8 functions of the liver
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1. blood storage
2. blood filtration 3. carbohydrate metabolism (gluconeogenesis, glycogenesis, storage of glycogen) 4. fat metabolism 5. protein metabolism (urea) 6. detoxification 7. erythrocyte destruction 8. vitamin storage |
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What happens to the pH of the blood when the liver mobilizes fat or protein for energy?
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The acidity of the blood increases
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Name 3 functions of the kidney
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1. excrete waste products (urea, uric acid, ammonia and phosphate)
2. maintain homeostasis of body fluid volume and solute composition 3. help control plasma pH |
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The functional unit of the kidney is the __________.
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Nephron
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Bowman's Capsule
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A cup-shaped structure around the glomerulus of each nephron of the vertebrate kidney.
It serves as a filter to remove organic wastes, excess inorganic salts, and water |
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Glomerulus
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The first capillary bed of the nephron that blood flows into
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Renal Corpuscle
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The capsule that contains Bowman's capsule and a glomerulus
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The fluid that finds its way into the Bowman's capsule is called _________ or __________ _______.
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1. Filtrate
2. Primary urine |
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Where does most reabsorption take place?
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The proximal tubule
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Juxtaglomerular apparatus
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Monitors filtrate pressure in the distal tube
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