5.2 Excretion

Question 1

what products must be excreted

Answer 1

carbon dioxide
nitrogen-containing compounds e.g urea
other compounds, e.g bile pigment in faeces

Question 2

what are the 4 excretory organs?

Answer 2

lungs
liver
kidneys
skin

Question 3

page 25 sutff

Question 4

what is the formula for deamination

Answer 4

amino acid + oxygen = keto acid + ammonia

Question 5

what is the formula for urea

Answer 5

ammonia + carbon dioxide = urea + water

Question 6

what is the function of bile

Answer 6

used for digestion and excretion

Question 7

what is the route bile takes

Answer 7

liver > gall bladder where it is stored. bile pigments such as bilirubin will leave in faeces

Question 8

what are the holes in liver lobules

Answer 8

inter-lobular vessels

Question 9

what are the collumns of liver cells called

Answer 9

sinusoid

Question 10

what are kupffers and what do they do

Answer 10

specialised macrophages that breakdown and recycle old red blood cells, breakdown produces bilirubin

Question 11

what are the cells in the liver called

Answer 11

hepatocytes

Question 12

what are the metabolic functions of the liver

Answer 12

controls glucose levels
synthesis of bile, plasma proteins, cholersterol
synthesis of rbc
storage vitamins
detoxificaiton
breakdown of hormones
destruction of rbc

Question 13

enzymes used in detoxification

Answer 13

catalase - converts hydrogen peroxide to oxygen and water (high turnover number)
cytochrome P450 - cocaine and medicinal drugs

Question 14

how is alcohol broken down

Answer 14

enzyme ethanol dehydrogenase , final compound is ethanoate.

Question 15

page 29 ornitihine cycle or smthg

Question 16

label a kidney

Question 17

what are the tubules in the kidney called

Answer 17

nephrons

Question 18

what are the two labels for the arterioles in the bowmans capsule glomerular capillary

Answer 18

efferent and afferent

Question 19

what are the cells on the isnide of the bowmans capsule

Answer 19

podocytes

Question 20

what is the basement membrane made of

Answer 20

mesh of collagen fibres

Question 21

what are the 3 parts to the nephron

Answer 21

proximal convoluted tubules
loop of henle
distal convoluted tubule

Question 22

how does blood flow through the glomerulus

Answer 22

the afferent arteriole is smaller and has a higher pressure than efferent

Question 23

what is filtered out of the blood

Answer 23

water
amino acids
glucose
urea
inorganic mineral ions (NA, CL, K)

Question 24

What hapopens in the PCT

Answer 24

85% fluid reabsorbed which decreases water potential

Question 25

what happens in the descending limb

Answer 25

additional mineral ions and reduction of water

Question 26

what happens in the ascending limb

Answer 26

mineral ions activley transported out and water in

Question 27

what happens in collecting duct

Answer 27

removal of water leaves urine

Question 28

what happens at the cells idk

Answer 28

sodium in by active transport and cotransports glucose or amino acids which reduce water potential so water enters cells

Question 29

page 34 diagram

Question 30

what happens to the walls of the collecting duct on a cool day

Answer 30

become less permeable so less water is reabsorbed

Question 31

what happens to the walls of the collecting duct on a warm day

Answer 31

becomes more permeable so that more water is reabsorbed

Question 32

What is the hormone produced to signal permeability of the collecting duct

Answer 32

antidiuretic hormone (ADH)

Question 33

how does ADH afffect wall permeability

Answer 33

more adh signals for the vesicles containing aquaporins to fuse with cell surface membrane and becomes more permeable less is the opposite and removes aquaporins

Question 34

how does the body signal for more or less ADH

Answer 34

osmoreceptors in the hypothalamus shrivel when the water potential is low in the blood so signal for neurosecretory cells

Question 35

page 37 diagram