Topic 17: Excretory System (Osmoregulation and Excretion)

Question 1

Greater osmotic pressure occurs in areas of

Answer 1

higher solute concentration

Question 2

Osmoregulators hypotonic to environment constantly

Answer 2

lose water

Question 3

Examples of osmoregulators hypotonic to environment

Answer 3

sea animals and terrestrials

Question 4

Osmoregulators hypertonic to environment constantly

Answer 4

gain water

Question 5

Examples of osmoregulators hypertonic to environment

Answer 5

Freshwater fish, amphibians, etc.

Question 6

Number of nephrons in humans

Answer 6

1 M nephrons in humans

Question 7

expanded part of ureter that receives urine from kidney

Answer 7

Renal pelvis

Question 8

tuft of capillaries in kidney

Answer 8

Glomerulus

Question 9

expanded end of nephron tubule surrounding glomerulus

Answer 9

Bowman’s capsule

Question 10

returns 2/3 of water and NaCl from filtrate

tubule after bowman’s capsule; located in renal cortex

Answer 10

Proximal tubule

Question 11

creates hypertonic interstitial fluid in medulla

water leaves in descending loop

Na+ and Cl- actively pumped out in ascending loop

tubule loop into medulla, unique to mammals and birds

Answer 11

Loop of Henle

Question 12

H+, K+, other solutes actively pumped into filtrate from the blood

Water leaves filtrate because it’s hypertonicity compared to blood

tubule after loop of Henle; located in renal cortex

Answer 12

Distal tubule

Question 13

water leaves filtrate due to its hypertonicity compared to blood

water permeable

drains from tubule at cortex, merges with other ducts in medulla, empties urine to renal pelvis

Answer 13

collecting duct

Question 14

How much blood passes through kidneys each day

Answer 14

2000 L of blood

Question 15

How much fluid is taken from blood at glomerulus

Answer 15

180 L fluid

Question 16

Urine expelled each day

Answer 16

1-2 L

Question 17

Flow of glomerular filtrate

Answer 17

nephron tubule at Bowman’s capsule

passes through proximal tubule

loop of Henle

distal tubule

exits as urine into collecting duct

Question 18

Parts of nephron that are water permeable

Answer 18

distal tube and collecting duct

Question 19

How is ammonia obtained

Answer 19

when amino acids are catabolized

Question 20

method of excretion by secreting from gills

Answer 20

flushing

Question 21

method of excretion by cartilaginous fishes, adult amphibians, and mammals

Answer 21

Detoxification

Question 22

Method of excretion where ammonia is converted to urea

Answer 22

Detoxification

Question 23

method of excretion by reptiles and birds

Answer 23

Insolubilization

Question 24

Method of excretion where ammonia converted to uric acid (not water soluble, precipitates, little loss of water)

Answer 24

Insolubilization

Question 25

How is uric acid obtained

Answer 25

nucleic acid degradation

Question 26

enzyme that turns uric acid into allantoin

Answer 26

uricase

Question 27

These animals secrete uric acid because they have no uricase

Answer 27

Humans, apes, and dalmations

Question 28

what uric acid turns into after uricase enzyme

Answer 28

Allantoin

Question 29

hormone released by posterior pituitary

Answer 29

Antidiuretic hormone (ADH)

Question 30

Hormone that causes more water reabsorbed

Answer 30

Antidiuretic hormone (ADH)

Question 31

Hormone that increases number of opened water channels in membranes of collecting ducts

Answer 31

Antidiuretic hormone (ADH)

Question 32

hormone released in response to water conservation

Answer 32

Antidiuretic hormone (ADH)

Question 33

hormone released by adrenal cortex

Answer 33

Aldosterone

Question 34

hormone released in response to low [Na+] in blood

Answer 34

Aldosterone

Question 35

hormone that increases blood volume (greater retention of salt and water)

Answer 35

Aldosterone

Question 36

hormone that increases Na+ reabsorption in distal tubules

Answer 36

Aldosterone

Question 37

released by right atrium when stretched by increased blood volume

Answer 37

Atrial natriuretic hormone

Question 38

Decreases blood volume (greater excretion of salt and water)

Answer 38

Atrial natriuretic hormone