physiology

Question 1

describe the structure of a capillary

Answer 1

single layer of endothelial cells

Question 1

role of terminal arterioles

Answer 1

regulate regional blood flow to the capillary bed

Question 2

role of precapillary sphincters

Answer 2

regulate flow in few tissues e.g. mesentary

Question 3

what is ultra-filtration

Answer 3

exchange across the capillary wall of protein free plasma

Question 4

how do lipid soluble substances diffuse into capillaries

Answer 4

through endothelial cells

Question 5

how do water soluble substances diffuse into capillaries

Answer 5

through water filled pores

Question 6

how do we calculate net filtration pressure

Answer 6

forces favouring filtration - forces opposing filtration

Question 7

what is the name of forces involved in transcapillary fluid flow

Answer 7

starling forces

Question 8

where is filtration favoured in a capillary

Answer 8

at the arteriolar end

Question 9

where is reabsorption favoured in a capillary

Answer 9

at the venular end

Question 10

what are the 2 forces that favour filtration

Answer 10

capillary hydrostatic pressure
interstitial fluid osmotic pressure

Question 11

what is capillary hydrostatic pressure

Answer 11

pressure due to the blood flow across the capillaries

Question 12

role of capillary hydrostatic pressure

Answer 12

forces water out of the capillary

Question 13

what is interstitial fluid osmotic pressure

Answer 13

pressure of the proteins in the interstitium

Question 14

role of interstitial fluid osmotic pressure

Answer 14

pulls fluid out of the capillary (negligible)

Question 15

name the 2 forces that oppose filtration

Answer 15

capillary osmotic pressure
interstitial fluid hydrostatic pressure

Question 16

what is capillary osmotic pressure

Answer 16

the pressure due to the presence of plasma proteins

Question 17

role of capillary osmotic pressure

Answer 17

draws water from the interstitium back into the capillary

Question 18

what is interstitial fluid hydrostatic pressure

Answer 18

pressure of the fluid in the interstitium

Question 19

role of interstitial fluid hydrostatic pressure

Answer 19

forces fluid back into the capillary (negligible)

Question 20

what do starling forces favour in pulmonary capillaries

Answer 20

reabsorption

Question 21

benefit of starling forces in pulmonary capillaries

Answer 21

prevents the accumulation of interstitial fluid in the lungs (would affect gas exchange)

Question 22

what is oedema

Answer 22

accumulation of fluid in the interstitial space

Question 23

where in the body is ammonia synthesised

Answer 23

in the liver

Question 24

what mediates bile excretion

Answer 24

ATP

Question 25

what happens during phase 1 of drug metabolism

Answer 25

oxidation, reduction and hydrolysis

Question 26

what is phase 1 of drug metabolism done by

Answer 26

CYP450 in the endoplasmic reticulum of hepatocytes

Question 27

what happens in phase 2 of drug metabolsim

Answer 27

conjugation in the cytoplasm of hepatocytes

Question 28

what happens in phase 3 of drug metabolism

Answer 28

secretion into the bile

Question 29

what is stored in the liver

Answer 29

fat soluble vitamins iron, copper glycogen

Question 30

role of kupffer cells in the liver

Answer 30

digest/destroy particulate matter

Question 31

where is bile produced

Answer 31

hepatocytes

Question 32

roles of bile

Answer 32

assist micelle formation, neutralise chyme, protection of mucosa

Question 33

role of the gallbladder in bile production

Answer 33

where it is stored and concentrated

Question 34

secretion of bile during a meal (3)

Answer 34

chyme in duodenum stimulates gall bladder smooth muscle contraction sphincter of oddi opens bile spurts into the duodenum

Question 35

how does bile enter the duodenum

Answer 35

via cystic and common bile ducts

Question 36

what is liver cirrhosis

Answer 36

bands of fibrosis separating regenerative nodules of hepatocytes

Question 37

what commonly causes liver cirrhosis

Answer 37

alcohol consumption and Hep C

Question 38

is liver cirrhosis reversible ?

Answer 38

NO

Question 39

pathophysiology of liver cirrhosis

Answer 39

chronic inflammation damages liver leading to activation of hepatic stellate cells in the space of dis increase fibrosis leading to cirrhosis

Question 40

name some clinical signs of compensated cirrhosis

Answer 40

spider naevi palmar erythema clubbing gynaecomastia

Question 41

clinical features of decompensated liver cirrhosis

Answer 41

jaundice ascites encephalopathy easy bruising

Question 42

investigations for liver cirrhosis

Answer 42

serum markers imaging biopsy

Question 43

what is used to determine the level of liver damage in cirrhosis

Answer 43

liver elastography

Question 44

serum markers in liver cirrhosis

Answer 44

decreased albumin increased prothrombin time increased bilirubin