Urinary System Overview

Question 1

how many times do kidneys filter entire blood plasma volume each day?

Answer 1

60 times

Question 2

how much of body’s resting energy is used to excrete waste as urine

Answer 2

25%

Question 3

how much glomerular filtrate is initially removed from blood daily?

Answer 3

~ 47 gallons (99% is reabsorbed)

Question 4

how much filtrate enters collecting ducts per day?

Answer 4

~ 0.5 gal

Question 5

organs of urinary system (6)

Answer 5

• kidneys (2)
• ureters (2)
• bladder
• urethra

Question 6

pathway of waste out of body via urinary system

Answer 6

kidney –> corresponding ureter –> bladder –> urethra –> out of body

Question 7

functions of kidneys (3)

Answer 7

1. fluid homeostasis
2. filtration of waste
3. homeostasis of blood volume + chemical composition

Question 8

micturition

Answer 8

aka urination: act of emptying bladder

Question 9

3 processes necessary for body to filter blood + retain important materials

Answer 9

1. filtration (in glomerulus)
2. reabsorption (in renal tubules)
3. secretion (in renal tubules)

Question 10

urine gets color from

Answer 10

urochrome (pigment derived from metabolic breakdown of hemoglobin)

Question 11

normal appearance of urine (3)

Answer 11

• clear
• pale to deep yellow depending on body’s hydration
• slightly aromatic but not pungent unless stale

Question 12

2 categories of fluid in body

Answer 12

1. intracellular fluid

2. extracellular fluid

Question 13

intracellular fluid

Answer 13

• located inside cells

- makes up 60% of fluid in body (~25L for 150lb male)

Question 14

extracellular fluid

Answer 14

• located outside cells

- makes up 40% of fluid in body (~15L for 150lb male)

Question 15

2 types of extracellular fluid

Answer 15

1. plasma

2. interstitial fluid

Question 16

plasma

Answer 16

• fluid portion of blood

- makes up about 8% of fluid in body (~3L for 150lb male)

Question 17

interstitial fluid

Answer 17

• fluid in microscopic spaces between cells

- makes up about 32% of fluid in body (~12L for 150lb male)

Question 18

normal pH range of urine

Answer 18

4.5 - 8

Question 19

normal density range of urine

Answer 19

1.003 (dilute) - 1.035 (concentrated)

urine = 95% water, 5% solute

Question 20

most prevalent solute in urine

Answer 20

urea

Question 21

other common solutes in urine (10)

Answer 21

• uric acid
• creatinine
• ammonia
• Na +
• K+
• PO3-
• Ca
• Mg
• Cl
• HCO3-