4/29- Urinary System (Exam 4)

Question 1

What are the 3 basic functions of the urinary system?

Answer 1

1) removal of nitrogenous waste
2) water balance (regulating water levels)
3) ion regulation or electrolyte balance of salt balance

Question 2

Where does nitrogenous waste come from?

Answer 2

Amino acids

Question 3

What is deamination?

Answer 3

Amino groups (NH2) is removed from amino acid

Takes place in liver

Produced waste product that is toxic and needs to be removed

Question 4

What are the 3 molecules that can be derived from the amino group (NH2)?

Answer 4

1) ammonia- highly toxic
2) uric acid
3) urea

Question 5

What is uric acid?

Answer 5

Insoluble in water

Crystallizes

Tiny amounts in humans

Question 6

What is gout?

Answer 6

When uric acid crystallizes in joint capsule of big toe

Need to cut down protein

Question 7

What is urea?

Answer 7

Human waste product

Insoluble in water

Must be removed from body

Question 8

What is the nephron and it’s 3 basic functions?

Answer 8

Basic functional unit of kidney

Microscopic

1) filtration- filters blood (Bowmans capsule)
2) reabsorption- proximal and distal convoluted tubule
3) secretion- Na+ out, K+ and H+ in

Question 9

What do mammals have and why?

Answer 9

Loop of Henle

Makes urine more concentrated that blood plasma

Question 10

What is the Bowmans capsule and it’s 2 layers?

Answer 10

Where filtration takes place

2 layers

1) parietal layer- outer
2) visceral layer- inner

Question 11

What are podocytes?

Answer 11

Cells visceral layer of bowmans capsule

Fit over glomerulus

Have pedicels

Question 12

What are pedicels?

Answer 12

Finger like process inside podocytes

Interfinger each other

Question 13

What are filtration slits?

Answer 13

Spaces between pedicels where water gets through

Question 14

What are fenestrated capillaries?

Answer 14

Found in glomerulus

Have pore like openings

Water goes out and into filtration slits than to hollow interior of bowmans capsule

Question 15

What is the proximal convoluted tubule?

Answer 15

Reabsorbs useful material

Cells that form wall- simple cuboidal epithelium

Microuilli increase absorption

Question 16

What is the counter- current exchange system?

Answer 16

Happens in loop of henle

Filtrate flowing in opposite direction

Question 17

What is the efferent arteriole?

Answer 17

Brings things in and out of nephron

Question 18

What is the peritubular capillaries?

Answer 18

Wraps around nephron leaving afferent arteriole

Pumping in from this blood supply

Pumping out goes to thia blood supply

Question 19

What is the vasa recta?

Answer 19

Capillary coming out of the efferent arteriole

Capillary loops around loop of henle and water is picked up by the blood

Question 20

What is the Antidiuretic hormone (ADH)?

Answer 20

Secretion of posterior pituitary gland

Cause kidney to conserve water

Affects collection duct to become more permeable to water- allows more water than usual to leave the urine and vasa recta conserves the water

Question 21

What is the glomerular hydrostatic pressure (GHP)?

Answer 21

Pushing water and dissolved material out of the blood into bowmans capsule

Greater pressure

Bp in glomerulus

Question 22

What is the capsular hydrostatic pressure (CsHP)?

Answer 22

Liquid that is collecting inside the bowmans capsule is generating a force of its own

Question 23

What is the net hydrostatic pressure (NHP)?

Answer 23

NHP= GHP- CsHP

Question 24

What is the blood colloid pressure (BCOP)?

Answer 24

Suspended plasma proteins

Draws water into the blood

Question 25

What is the filtration pressure (FP)?

Answer 25

Overall force moving material in or out of the blood FP = NHP- BCOP

Question 26

What is the glomerular filtration rate (GFR)?

Answer 26

Important measure of the health of the kidney Amount of filtrate the kidney produces each minute

Question 27

What is creatinine?

Answer 27

Breakdown of creatine phosphate Leaches out of the blood and is filtered out by kidneys

Question 28

What is the creatinine clearance test?

Answer 28

Combo of blood test and urine analysis Analyze blood to see how much creatinine is in the blood Measure how much is in the urine (collected over 24hrs)

Question 29

What are 3 ways to regulate the GFR?

Answer 29

1) auto regulation 2) hormonal or other chemical regulations 3) autonomic regulation

Question 30

What is auto regulation?

Answer 30

Self regulation in kidney Dilate afferent arteriole- more blood to rush in under high pressure in glomerulus Constrict efferent arteriole- builds up pressure when closed and raises GFR

Question 31

What is hormonal regulation?

Answer 31

Renin- angiotestin system Antiotensinogen—> angiotensin 1—> angiotensin 2 (vasoconstrictior)

Question 32

What is the juxtaglomerular apparatus?

Answer 32

Where renin comes from Consists of 2 things 1) juxtaglomerular cells 2) macula Densa Cells measure bp drops N-+ ion levels drop in filtrate ——-renin is produced

Question 33

What are juxtaglomerular cells?

Answer 33

Thick cells that surround walls of afferent arteriole Measures bp

Question 34

What is macula densa?

Answer 34

Columnar cells in wall of distal convoluted tubule Measure Na+ ion levels in filtrate

Question 35

What is autonomic regulation?

Answer 35

Visceral motor Sympathetic nerves connecting to arteries and raIses bp and GFR Bp raises GFR raises

Question 36

What does angiotensin 2 do?

Answer 36

Stimulates the zoma glomerulosa of the adrenal cortex Secretes aldosterone

Question 37

What is aldosterone?

Answer 37

Sodium regulator Causes rest of distal convoluted tubule to save even more sodium to the body and not lose it in the urine