Kidneys

Question 1

What is water movement faciitated by

Answer 1

channels, osmosis, filtration, and absorption

Question 2

U/P =1

Answer 2

isoOsmotic

Question 3

U/P > 1

Answer 3

Urine is hyperOsmotic ~ Urine releases solutes and solute content is decreased in plasma

Dehydration

Question 4

U/P < 1

Answer 4

Urine is hypoOsmotic ~ Urine excretes water and solute content is released into plasma

Over hydration

Question 5

3 reasons animals need water

Answer 5

respiratory water loss
fecal loss
urinary loss

Question 6

what 3 things does the kidney produce

Answer 6

filtrate, ultrafiltrate, primary urine

Question 7

what is the output from kidneys after processing

Answer 7

definitive Urine

Question 8

3 functions of kidney

Answer 8

Filtration - rate is regulated
Absorption - filtered components can be re-absorbed
Secretion - Components that arent filtered are then added to filtration

Question 9

What collects urine output?

Answer 9

Renal Pelvis, then drains to ureter which travels to bladder

Question 10

Where are nephrons located?

Answer 10

Cortex and Medulla

Question 11

What are nephrons composed of

Answer 11

1) Bowman’s capsule
2) Proximal Tubules
3) Loop of Henle
4) Distal Tubules
5) end at collecting duct

Question 12

2 capillary networks of Nephrons

Answer 12

Glomerular capillaries - Bowman’s capsule
Pertibular Capillaries - Loop of Henle

Question 13

Blood pathway in Kidney

Answer 13

1) Afferent Ateriole

2) Glomerular Capillaries (filtration step takes to bowman’s capsule)

3) Efferent Arteriole

4) Pertibular Capillaries (secretion can take to loop of Henle and absorption can take from Loop of henle to here)

5) Venules

Question 14

Structure and Function of glomerular filtration

Answer 14

Nephrons enclose around the Glomerular capillaries.

Filtration is extremely fast here compared to other capillaries, this is due to highly porous nature.

Question 15

Urine pathway in Kidneys

Answer 15

Glomerular Capillaries

Bowman’s Capsule

Proximal Tubule

Loop of Henle

Distal Tubule

Collecting Duct

Ureter

Bladder

Question 16

What drives glomerular filtration rate?

Answer 16

Hydrostatic pressure drives blood into capsule, Osomotic pressure and hydrostatic pressure within the capsule can resist this movement

Question 17

How can GFR be regulated?

Answer 17

contraction and dilation of arterioles to affect pressure

Question 18

What is the dominant activity to modify filtrate

Answer 18

Reabsorption

Question 19

What is the fate of filtered solutes?

Answer 19

majority are re absorbed

Glucose - 100%
Na+ and H2O nearly completely absorbed

Some are secreted into tubules like waste

Question 20

how does length of loop of henle affect urine concentration

Answer 20

longer makes higher conc urine

Question 21

Loop of henle function

Answer 21

Creates the osmotic gradient in the medulla that allows the kidney to make hyperosmotic (concentrated) urine when you need to save water.

Question 22

when is ADH secreted by posterior pituitary

Answer 22

High plasma osmolarity or low plasma volume

Question 23

what does ADH do

Answer 23

tell the kidney to absorb more water into the blood

Question 24

Descending Limb in loop of henle function

Answer 24

Permeable to water

NOT permeable to solutes

Water leaves → filtrate becomes more concentrated as it moves downward

Think: “Water OUT.”

Question 25

Ascending Limb

Answer 25

Impermeable to water Actively pumps out Na⁺, K⁺, Cl⁻ Filtrate becomes more dilute as it rises Think: “Salt OUT.

Question 26

what does the Atrial natriuertic peptide do in kidney regulation

Answer 26

inhibit sodium reabsorption and reduce fluid vol.

Question 27

Medullary thickness is a measure of what

Answer 27

length of the loops of henle

Question 28

What does the single effect do

Answer 28

ensures filtrate leaves loop of henle more dilute than plasma

Question 29

What does ANP do

Answer 29

reduce fluid volume and blood pressure

Question 30

How does ADH presence affect osmolarity between filtrate and interstitial fluid at the collecting duct.

Answer 30

becomes osmotic - generates hyper osmotic urine

Question 31

What does aldosterone do

Answer 31

increase fluid volume and blood pressure

Question 32

Renin-Angiotensin system

Answer 32

Juxtaglomerular cells secrete renin in response to low BP (low sodium reabsorption) and low osmolarity.

Question 33

What does Renin do

Answer 33

Cleaves angiotensin which ultimately increases volume and pressure.