Midterm study cards

Question 1

Enterokinase

Answer 1

Brush border enzyme - peptidase - that activates trypsin (and indirectly other pancreatic juice enzymes) - deficiency results in protein malnutrition

Question 2

Phosphatases

Answer 2

Ca2+, Mg2+ and -ATPase needed for the absorption of dietary calcium
enzyme activity regulated by Vit D

alkaline phasphatases remove phosphate groups from organic mlcs

Question 3

Paneth cells

Answer 3

in the crypts of LIekehurn (intestinal crypts)
secrete antibacterial mlcs (lysozyme and antimicrobial peptides) to protect the intestine

Question 4

haustrum

Answer 4

part of the large intestine after the descending colon but before the sigmoid colon

Question 5

Why does diarrhea happen?

Answer 5

pathogenic bacteria take over the colon so it gaotta slought off the colon epithelium

Question 6

sinusoids

Answer 6

large capillaris in the liver (lined with hepatic cells)
also lined by endothelial cells
contain Kupffer cells (phagocytes)

Question 7

Kupffer cells

Answer 7

these phagocytes in the liver that wander around and pick up debris

Question 8

What are the two blood inputs of the liver?

Answer 8

portal vein (from intestines)
hepatic artery (blood from heart)

Question 9

exocrine functions of the liver

Answer 9

right and left hepatic ducts
make bile, stored in gallbladder
common bile duct goes into small intestines

Question 10

Major functions of the liver

Answer 10

1. detoxification of blood (phagocytosis by kupffwer cells, prod. of urea and less toxic mlc)
2. carbohydrate metabolism (glucose to glycogen and vice versa) also gluconeogenesis and release of glucose to blood
3. Lipid metabolism (synthesis of cholesterol and triglycerides. excretion of chelestero and production of ketone bodies
4. protein synthesis (production of albumin and plasma transport proteins
5. secretion of bile

Question 11

HOw does liver make bile?

Answer 11

• derivative of heme group (minus the iron) is converted to bilirubin
• biliruben is carried in blood on albumin proteins
• taken up by liver, mixed with glucoronic acid
• is now water soluble and can be secreted as bile
• converted by bacteria to urobilinogen

Question 12

Pancreas exocrine function

Answer 12

releases a cocktail of over 20 enzymes including:
- pancreatic amylase
- pancreatic lipase
- trypsin

Question 13

Pancrease endocrine function

Answer 13

makes insulin and glucagon yeah

Question 14

alpha dextrinase

Answer 14

takes small glucose polymers and breaks into multiple mlcs of glucose

Question 15

Ptyalin

Answer 15

salivary amylase - hydrolyses starch into maltose and other small glucose polymers

Question 16

What is the first pass effect?

Answer 16

as blood passes through plood vessels of liver, much of nutrient load is removed

Question 17

Is cholesterol absorbed without digestion?

Answer 17

YES

Question 18

Hepatic portal system

Answer 18

1. small intestine absorbs products of digestion -
2. nutrient molecules travel in hepatic portal vein to liver
3. liver monitors blood content
4. blood enters circulation by way of hepatic vein

Question 19

Cholesterol

Answer 19

85% produced in liver
15% from diet
is transported in the vlood associated with lipoproteins, HDLs
is a major component of cell membranes

Question 20

Why can’t enxymes access lipids?

Answer 20

Cause lipids aren’t water soluble so bile salts are required to emulsify them so enzymes like lipases (present in pancreatic juice) can access them

Question 21

pancreatic lipase

Answer 21

main enzyme that breaks down lipids - triglycerides into fatty acids and monoglycerides
why most of lipid digestion, if not all, happens in small intestine

Question 22

chylomicrons

Answer 22

Chylomicrons are large lipoprotein particles that transport dietary fat from the intestines to the liver and other tissues.
droplets of triglycerides that leave the cell by exocytosis and enter the lacteals of villi
secreted into the central lacteal
they reach the blood through the Thoracic Duct
in the vlood, they add ApoE protein which helps it bind to capillaries in target muscles and adipose tissue
after the triglycerides are broken up, the depleted chylomicron particle goes back through circulation to liver

Question 23

proteases

Answer 23

pepsin in the stomach
functions at pH of 2-3
inhibited at pH over 5
one of the only enzymes capable of digesting collagen (connective tissue in meats)
first enzyme that starts to break down polypeptides into smaller chains of AAs

Question 24

Proteolytic enxymes

Answer 24

• from pancreas (act in duoden. and jejenum)
• break down protein to smaller chains of AAs
• trypsin
• chymotrypsin
• carboxypeoptidase
• protelastase

Question 25

peptidases

Answer 25

brush border enzymes that break down polypeptides into their individual amino acids

Question 26

endopeptidases vs. exopeptidases

Answer 26

endo cleave internal protein bonds exo cleave off the ends

Question 27

How are water soluble vitamins absorbed?

Answer 27

diffuse in blood (vit B1, B2, B3, B6) except B12 this combines with intrinsic factor produced by stomach which intestine absorbs by endocytosis

Question 28

vasoconstriction

Answer 28

decreases blood flow to capillary bed

Question 29

vasodilation

Answer 29

increases bloodflow to capillary bed

Question 30

vocal chords

Answer 30

folded tissyes of the larynx

Question 31

lung compliance

Answer 31

= change in lunge volume over transpulmonary pressure - its the distendability of the lung

Question 32

pleural membranes

Answer 32

how the lungs stick to chest wall - 2 membranes with no space, technically pleural space and pleural fluid btw them tha

Question 33

pleural fluid

Answer 33

mucous rich lubricating fluid that holds the 2 membranes together lubricant allows lucgs to slide easily within thoracic cavity and inflate and deflate

Question 34

angia

Answer 34

chest pain

Question 35

myocardial infraction

Answer 35

results if there's a clot, not gonna depolarize and repolarize properly can lead to myochardeal ischeamia = heart attack

Question 36

brady cardia

Answer 36

low HR <60bpm

Question 37

tachycardia

Answer 37

high resting HR >100bpm

Question 38

Ca2+ induced Ca2+ release

Answer 38

Ca2+ from voltage gated ion channels between the ECF and cytoplasm = messenger for the release channels 1. Ca2+ diffuses from ECF to cytoplasm 2. Ca2+ release channels on SR open 3. Ca2+ released from SR binds to sarcomere, stimulates contraction 4. Ca2+ ATPase pumps calcium back into SR 5. Myocardial cell relaxes

Question 39

sarcomere

Answer 39

section of myofibril (muscle tissue) fibre between Z - discs

Question 40

Myosin

Answer 40

thick band with the heads

Question 41

Actin

Answer 41

thin filaments

Question 42

troponin

Answer 42

attatched to tropomyosin which attatches to actin and prevents myosin heads from binding attatchment of Ca2+ to troponin causes movement of the troponin-tropomyosin complex so myosin can now bind and do power stroke and crossover = contraction

Question 43

3 main differences between skeletal and cardiac muscle

Answer 43

1. skeletal muscle requires external stimulation by somatic motor nerves vs. cardiac muscle which provides action potentials automatically via SA node 2. Skeletal muscle = long and fibrous vs. myocardial - short, branched and interconnected 3. skeletal have direct contraction coupling btw tranverse tubules and SR vs. cardiac cellls have Ca2+ induced Ca2+ release

Question 44

Parasympathetic innervation

Answer 44

Is from cranial and saccral nerves cranial does everything except repro. organs, bladder, adrenal gland and kidney (which is what saccral innervates)

Question 45

Sympathetic innervation

Answer 45

from Thoracic and Lumbar thoracic does everything except adrenal, kidney, repro organs and bladder which is what lumbar does