4: reabsorption and secretion

Question 1

in ____ ____, water and solutes can travel thru the tubular epi, either thru the __ route (thru cell memb) or the __ route (bt cells via tight jxn)

Answer 1

tubular resorption
transcellular
paracellular

Question 2

in tubular resorption, water is always absorbed by ___ mechanism (osmosis)

Answer 2

passive

Question 3

__ __ is the limit to the rate at which a solute can be transported during active reabsorption or secretion

Answer 3

transport maximum

Question 4

some substances that are passively absorbed don’t demo a transport maximum, rate dep on other things, is then called __ __ transport

Answer 4

gradient time

Question 5

transport type in which the rate dep on:

• electrochem gradient
• perm of memb to substance
• time the fluid containing the substance in tubule

Answer 5

gradient time

Question 6

some actively transported substances can exhibit characteristics of gradient time transport , such as:

Answer 6

Na reabsorption in prox tubule

Question 7

sodium transport in the PROX tubules obey __ __ transport principles

• greater [Na] in prox tubule, greater reabsorp rate
• slower flow rate, more Na reabsorbed

Answer 7

gradient time

Question 8

65% of filtered water and Na are reabsorbed in ___ ___ before reaching the _ _ _

Answer 8

proximal tubule

loop of henle

Question 9

thin descending segment
thin ascending segment
thick ascending segment
–are the three parts of the :

Answer 9

loop of henle

Question 10

the THICK ASCENDING segment of loop of henle is made of thick epi cells and functions in active resorption of (3):

Answer 10

Na
Cl
K

Question 11

transport mechanism found in the thick ascending part of loop of henle

Answer 11

sodium-hydrogen counter-transport (mechanism)

Question 12

late distal tubule and cortical collecting tubule is composed of what 2 cell types

Answer 12

principal

intercalated

Question 13

in late distal tubule & cortical collecting tubule, reabsorp of Na and secretion of K is controlled by ____

Answer 13

aldosterone

Question 14

permeability to water in late distal tubule and cortical collecting tubule is dependent on __

Answer 14

ADH

Question 15

hormone that increases water reabsorp in resp to dehydration

Answer 15

ADH

Question 16

w/o ADH, distal tubule & collecting ducts aren’t v. permeable to ___, and we would excrete large quantities of __ ___

Answer 16

water

dilute urine

Question 17

two net reabsorptive forces that FAVOR reabsorption

Answer 17

plasma colloid OP (32mmHg)

hydrostatic P in interstitium (6mmHg)

Question 18

two net reabsorptive forces that OPPOSE reabsorption

Answer 18

peritubular hydrostatic P (13mmHg)

OP of the renal interstitium (15 mmHg)

Question 19

net reabsorptive forces AND glomerular cap net filtration forces both =

Answer 19

10mmHg

Question 20

Kf (filtration coefficient) influences movement of fluid across caps and involves ___ __ and ___ of the capillary

Answer 20

surface area

permeability

Question 21

Kf x net reabsorptive forces =

Answer 21

reabsorption

Question 22

-if peritubular capillary hydrostatic pressure is raised, reabsorption rate is ____. if it is lowered, reabsorption rate ___

Answer 22

decreased

increases

Question 23

Na+ excretion in urine is called ____, and water excretion to reg BP is called __ __

• increases arterial P
• increase in urinary excretion of Na & H2O

Answer 23

natriuresis

pressure diresis

Question 24

___ is secreted by the zona glomerulosa cells of adrenal corex, and regs Na reabsorption and K secretion

Answer 24

aldosterone

Question 25

___ is released in resp to increased extracell [K] and angiotensin II levels

Answer 25

aldosterone

Question 26

___ increases water permeability and its primary fxn is to conserve water when bod is dehydrated

Answer 26

ADH

Question 27

___ is released in the cardiac atria when distended, inhibits the reabsorp of Na & water, and counteracts the renin-angiotensin system

Answer 27

ANP

Question 28

hormone that increases Na & water reabsorp and increases when BP is low/low extracell vol

Answer 28

angiotensin II

Question 29

hormone that stim aldosterone secretion, constrict efferent arterioles

Answer 29

angiotensin II

Question 30

hormone that directly stim Na resabsorp in prox tubule, loop of henle, distal tubule, collecting tubule

Answer 30

angiotensin II