Exam 3 Flashcards
1
Q
Name layers of GI tract - innermost to outermost
A
Mucosa
Submucosa
Muscularis Externa
Serosa
2
Q
What is the function of the mucosa?
A
Secretes mucus, digestive enzymes, absorbs end products of digestion
3
Q
What is the function of the submucosa?
A
nerve plexus surrounding GI tract
4
Q
What is the function of the muscularis externa?
A
segmentation and peristalsis
5
Q
What is the function of the serosa?
A
reduces friction
6
Q
4 Types of Gastric Pit Cells
A
Mucous neck cells
parietal cells
chief cells
enteroendocrine cells
7
Q
What do mucous neck cells produce?
A
mucous
8
Q
What do parietal cells produce?
A
HCl Acid to denature proteins
Intrinsic Factor for vitamin b absorption
9
Q
What do chief cells produce?
A
Pepsinogen to avtivate pepsin
Liapses
10
Q
What do enteroendocrine cells produce?
A
Chemical messengers that act as paracrines - serotonin and histamine
Hormones - somatostatin and gastrin
11
Q
What is pepsinogen? Who is it produced by? How is it activated?
A
Produced by chief cells, precursor to pepsin, activated by HCl
12
Q
Bile - What is its purpose? Where is it produced?? Where is it stored ?? What nutrient class is it used to digest?
A
1) Bile is fat emulsifier and carry away waste,
2) produced in liver
3) stored in gallbladder
4) Fats
13
Q
Phases of Swallowing
A
Buccal
Pharyngeal-esophogeal
14
Q
What is the Buccal Phase of swallowing
A
Voluntary contraction of tongue
15
Q
What is the 2. Pharyngeal-esophageal phase of swallowing?
A
involuntary
16
Q
3 parts of the small intestine - top to bottom
A
Duodenum
Jejunum
Illeum
17
Q
Where is the duodenum? What happens there?
A
1) retroperitoneal cavity;
2) complete first phase of digestion,
3) food mixed with enzymes and bile to break down food
18
Q
Where is the jejunum? What happens there?
A
1) Intraperitoneal cavity
2) absorb nutrients (carbs, fats, minerals, proteins and vitamins) and water
19
Q
Where is the illeum? What happens there?
A
1) intraperitoneal;
2) final digestive phase, absorbs bile acids, fluid and b-12;
3) contains villi
20
Q
Where does the majority of absorption occur?
A
Small intestine
21
Q
What are the small intestine modifications?
A
- Circular Folds
- Villi
- Microvilli
22
Q
Parts of Large Intestine - in order
A
- Cecum
- Appendix
- Colon
- Rectum
- Anal Canal
23
Q
Parts of Colon
A
Ascending, transverse, descending, sigmoid
24
Q
What is unique about large intestine?
A
Not essential for life; No food breakdown happens here
25
Role of small intestine
26
4 nutrient classes
carbs
protein
lipids
nucleic acids
27
What enzyme breaks carbs? Into what? Where does it travel?
1. Broken down by salivary amylase and pancreatic amylase
2. Into monosaccharaide
3. Enter bloodstream
28
What enzyme breaks proteins? Into what? Where does it travel?
1. Pepsin and Pancreatic Enzymes
2. Into amino acids
3. Bloodstream
29
What enzyme breaks lipids? Into what? Where does it travel?
1. Bile and Bile Salts, Pancreatic Lipases
2. Triglycerides
3. Lymph
30
How is water absorbed?
Osmosis
31
What is mechanical digestion? Where does each part occur?
Physical breakdown
Chewing (mouth)
Churning (stomach)
Segmentation (small intestine)
32
What is chemical digestion? Where does it occur?
Acids, Enzymes and Secretions break food into building blocks for nutrient absorption
Starts in mouth, then stomach and into small intestine
33
Where are microvilli found and what are they good for?
Found in small intestine
Good for final protein and carb digestion
34
What happens in glycolysis?
Breakdown of glucose into pyruvic acid then enters 1 of 2 pahways - no oxygen or oxygen
35
What do you start with in glycolysis? What is the end product?
1. Start with glucose (6 carbon)
2. Broke into 2 carbon pyruvate acid molecules each with 3 carbon
2 ATP
36
What is the molecule that enters the Krebs Cycle?
Coeyzyme A hooked onto acetic acid
37
How do you oxidize glucose?
Glycolysis
Krebs Cycle
Electron Transport Cycle
38
Where does glycolysis occur?
Cytoplasm/cytosol
39
In glycolysis, if no oxygen is available, what happens?
1. mitochondria not invovled
| 2. lactic acid produced
40
In glycolysis, if oxygen is available, what happens?
Enters Krebs cycle and Electron transport chain
Enters mitochondria
41
Where does the krebs cycle occur?
mitochondria
42
What is the end product of the krebs cycle?
6 CO2
8 NADH + H
2 FADH2
2 ATP
43
What happens in the electron transport chain?
Uses energy from krebs cycle to pump H across membrane into proton gradient, some H combined with O to produce water
44
What happens when you're abundant in ATP?
Absorpative/Fed State
Anabolsim > Catabolism
Dominated by insulin
Excess nutrients stored as fat if not used
45
What happens when you don't have any ATP?
Fasting State/Post Absorpative
Dominated by glucagon
Catabolism of fat, glycogen and proteins
46
What are the macronutrients?
Carbs, Lipids, Proteins
47
How much ATP is produced from carbs/proteins vs lipids?
carbs/proteins - 4
| lipids - 9
48
What are essential nutrients?
Nutrients that must be eaten because the body cannot synthesize them from other nutrients
49
What is anabolism?
synthesis of large molecules from small ones (amino acids to proteins)
50
What is catabolism?
hydrolysis of complex structures to simpler ones (proteins to amino acids)
51
Glycogenesis
making glycogen with excess glucose, occurs in liver and skeletal muscle
52
Glycolysis
breakdown of glucose to pyruvic acid
53
Glycogenolysis
breaking down glycogen in response to low blood glucose
54
Gluconeogenesis
new glucose from non-carbs, occurs in liver
55
Lipolysis
breakdown of stored fats into glycerol and fatty acids
56
Lipogenesis
synthesis of fat
57
What are the fat soluble vitamins? Where are they Stored?
A - converted from beta carotene
D - skin
E - stored in liver and fat tissue
K - colon
58
What molecules make up triglycerides?
Glycerol + 3 fatty acids
59
Where is urea produced?
The Liver
60
Where is Angiotensin II produced?
The Kidneys during the renin-angiotensin complex
61
Where is renin produced?
Produced by kidneys in granular cells to raise blood pressure to initiate angiotensin-alderstone mechanism
62
What are corticol nephrons? How are they different from juxtamedullary nephrons? Where are they found?
1) 85% of all nephrons,
2) short nephron loop, glomerulus further from the cortex-medulla junction; efferent arteriole supplies pertibular capillaries
3) found in cortex;
63
What are juxtamedullary nephrons? How are they different from corticol nephrons? Where are they found?
1) long nephron loop, glomerulus closer to cortex-medulla junction,
2) efferent arteriole supplies vasa recta
3) Found in renal medulla
64
What substances SHOULD be found in initial glomerular filtrate
Blood plasma minus blood cells and protein
65
What is filtration? Where does it occur?
movement of water and solutes from plasma to renal tubule; occurs in rental corpuscle in glomerulus
66
What is Reabsorption?
movement of water and solutes from tubule back into plasma; occurs in proximal convoluted tubule in cortex
67
Where does secretion occur?
Distal convoluted tubule
68
Hormone Controlled Reabsorption
Distal Convoluted Tubule - Sodium/Aldosterone, Calcium (PTH), Chrloride follows sodium
Collecting Ducts - H20/Water
69
Granular Cell - What do they do? Where are they
Sense blood pressure and secrete renin
| Enlarged smooth muscle of arteriole
70
Macular Densa - Where are they? What do they do?
Ascending limb
| Chemoreceptor for NaCl content of filtrate
71
Extraglomelular - What is it?
Gap junction, pass signals between macula densa and granular cells
72
Which layer of the alimentary canal is responsible for the movements of segmentation and peristalsis?
Muscularis externa
73
The pancreas secretes a number of products into the duodenum in the pancreatic juice. What are the functions of pancreatic juice?
1) Acidifying the contents of the duodenum
| 2) Neutralizing the chyme entering the duodenum from the stomach
74
In which segment of the alimentary canal does the majority of nutrient absorption occur?
Jejunum and ileum
75
What is the primary function of the large intestine?
Water absorption and feces formation
76
Weakening of the ________________ sphincter can lead to heartburn and GERD.
Gastro-esophageal
77
The segment of the small intestine that is first in line after the stomach is the
Duodenum
78
What is true about the liver?
Plays role in detoxifying blood
Target organ for diseases such as Hep A and Hep C
Produces Bile
79
What is the site of “intrinsic factor” production?
The parietal cells of the gastric pits
80
What is the site of hydrochloric acid production?
The parietal cells of the gastric pits
81
hich of the following is the breakdown product of carbohydrates?
Monosaccharides
82
True or False: B vitamins and Vitamin K are produced by bacteria in the large intestine
True
83
A scarring of the liver tissue as a result on long term chronic inflammation such as alcoholism is
Cirrhosis
84
The vermiform appendix is a worm-like structure that is attached to the
Cecum
85
Which type of nutrient does not enter the bloodstream directly, but enters the lymphatics as chylomicrons and is then dumped into the blood by the lymph vessels?
Fats
86
Glycolysis is the breaking of the 6-carbon glucose molecule into
Two 3-carbon Pyruvic acid molecules
87
Which of the statements about Glycolysis only is FALSE?
It occurs in the mitochondria
It does not consume or need oxygen to take place
It occurs in the cytoplasm
It can produce lactic acid
It occurs in the mitochondria
88
How many ATP are produced from glycolysis of a single glucose molecule?
2
89
When there is abundant
| ATP available in the cell, what occurs?
Lipgenesis
Glyocgen is produced
Glucose catabolism is inhibited
90
Which of the three nutrient classes below yields the highest amount of energy per gram?
Lipids
91
What is special about essential amino acids?
They must be provided in the diet; the body cannot synthesize them
92
The breakdown of organic macromolecules into their smaller units is called
catabolism
93
Which of the following statements are TRUE about the Absorptive (fed) state?
A. Glucagon secretion is stimulated
B. Occurs during periods of fasting, not right after a meal
C. Catabolism exceeds anabolism
D. Insulin secretion is stimulated
D. Insulin secretion is stimulated
94
Which of the following terms means the formation of glucose from non-carbohydrate molecules
Gluconeogenesis
95
Which term below refers to the breaking apart of glycogen to yield glucose?
Glycogenolysis
96
Which of the following is TRUE about the Post-Absorptive (fasting) state?
Anabolism exceeds catabolism
Glucagon secretion is inhibited
Insulin secretion is stimulated
Energy is provided by catabolism of stored nutrients such as lipids and glycogen
Energy is provided by catabolism of stored nutrients such as lipids and glycogen
97
The electron transport chain and oxidative phosphorylation produces large amounts of energy for the cell to use in the form of ATP. What is the part of the electron transport chain and oxidative phosphorylation that yields this ATP in the actual ETC?
The movement of hydrogen ions back into the cell at the site of ATP synthase
98
Aerobic breakdown of pyruvate occurs in which organelle of the cell?
mitochondria
99
Oxygen is necessary for the life of cells. What exactly is oxygen used for?
Oxygen is the Hydrogen ion acceptor in the electron transport chain
100
Where is glycogen stored in the body?
liver and muscle
101
What does GFR stand for?
Glomerular filtration rate
102
Which of the following processes are functions of the kidney?
Activation of Vitamin D
Gluconeogenesis
Release of Renin
Release of erythropoietin
103
Which of the following structures may be found in the medulla of the kidney?
Glomerulus
Proximal convoluted tubule
Loop of Henle
Afferent arteriole
Loop of Henle
104
What is the role of the the juxtamedullary nephrons?
Forming concentrated urine
105
Which of the following substances WOULD be found in the initial
glomerular filtrate?
Glucose
Red blood cells
White blood cells
Proteins
Glucose
106
Which part of the nephron is the primary site of REABSORPTION?
roximal convoluted tubule
107
What is meant by the “co-transport” or “secondary active transport” by the PCT?
When Na+ is actively transported, glucose and amino acid come along too
108
What part of the tubule is the primary site of hormone controlled reabsorption?
Distal convoluted tubule
109
How does ADH work?
Triggers reabsorption of water in the collecting ducts
110
Which of the following is the standard substance used to measure GFR?
Inulin
111
A patient had a disease that damaged his kidney, and now has kidney damage. The GFR is calculated as 50 ml/minute. How would you describe this damage?
Chronic damage. This is in the range for chronic renal disease.
112
A significant consequence of renal disease and reduced GFR is
High levels of nitrogen waste in blood
