Urinary

Question 1

what is excretion?

Answer 1

separating wastes from body fluids and eliminating them

Question 2

how does the respiratory system carry out excretion?

Answer 2

CO2, small amounts of other gases, and water

Question 3

how does the integumentary system carry out excretion?

Answer 3

water, inorganic salts, lactic acid, urea in sweat

Question 4

how does the digestive system carry out excretion?

Answer 4

water, salts, CO2, lipids, bile pigments, cholesterol and other metabolic waste

Question 5

how does the urinary system carry out excretion?

Answer 5

many metabolic wastes, toxins, drugs, hormones, salts, H+, and water

Question 6

what is metabolic waste?

Answer 6

waste produced by the body

Question 7

how is urea formed?

Answer 7

proteins -> amino acids -> NH2 removed -> forms ammonia (NH3)
then the liver converts NH3 to urea

Question 8

what is uric acid?

Answer 8

product of nucleic acid catabolism

Question 9

what is creatinine?

Answer 9

produce of creatine phosphate catabolism.

Question 10

what does glomerular filtration make?

Answer 10

creates plasmalike filtrate of blood

Question 11

what is tubular reabsorption?

Answer 11

removes useful solutes from filtrates and returns them to the blood

Question 12

what is tubular secretion?

Answer 12

removes waste from blood and adds them to filtrate

Question 13

how does water conservation occur?

Answer 13

the renal tubule removes water from the urine and returns it to the blood.

Question 14

what are the three barriers to fluid movement?

Answer 14

endothelial cell of glomerular capillary, basement membrane, and filtration slit.

Question 15

what are the forces in glomerular filtration?

Answer 15

blood hydrostatic pressure, colloid osmotic pressure, and capsular pressure.

Question 16

how is the glomerular filtration rate controlled?

Answer 16

by homeostatic mechanisms: renal autoregulation, sympathetic control, and hormonal control.

Question 17

how does the kidney autoregulate?

Answer 17

by myogenic mechanisms (smooth muscles), and tubuloglomerular feedback

Question 18

what does the PCT do?

Answer 18

reabsorbs ~65% of the glomerular filtrate

Question 19

when is the transport maximum reached?

Answer 19

when the transporters are saturated

Question 20

what is tubular secretion important for?

Answer 20

acid-base balance, waste removal, and clearance of drugs and contaminants

Question 21

which hormones are the DCT and collecting duct regulated by?

Answer 21

aldosterone, atrial natriuretic peptide, antidiuretic hormone.

Question 22

what is renal clearance?

Answer 22

volume of blood plasma from which a particular waste is completely removed in 1 min.

Question 23

what is osmoregulation?

Answer 23

maintenance of nearly constant osmotic pressure in the body

Question 24

what is isotonic?

Answer 24

two solutions with the same osmotic pressure

Question 25

what is hyperosmotic?

Answer 25

one solution has greater osmotic pressure than another

Question 26

what is hyposmotic?

Answer 26

one solution has lower osmotic pressure than another

Question 27

how does water move through the body?

Answer 27

digestive tract -> bloodstream -> tissues -> lymph nodes -> bloodstream

Question 28

what do osmoreceptors respond to?

Answer 28

rising osmolarity of the ECF, reduced blood pressure, and angiotensin II.

Question 29

what is aldosterone?

Answer 29

makes the kidney retain salt (comes from adrenal cortex)

Question 30

what does ADH respond to?

Answer 30

dehydration, loss of blood volume, and rising blood osmolarity.

Question 31

what is hypovolemia?

Answer 31

volume depletion of water and sodium but osmolarity remains normal

Question 32

which hormones regulate sodium?

Answer 32

aldosterone and ADH