Chapter 14 - Urinary System (Exam 3)

Question 1

Kidney Functions

Answer 1

Water balance, maintain osmolarity, qty and ECF ioins, Plasma volume (BP), pH, eliminates wastes, produces erythropoietin and renin, convert to vit d into active form

Question 2

Nephron

Answer 2

Functional unit of kidneys; Renal cortex (outer), Renal Medulla (inner); Vascular and tubular component

Question 3

Vascular Component

Answer 3

Renal a, afferent arterioles, glomerulus, efferent arterioles, peritubular capillaries

Question 4

Glomerulus

Answer 4

Tuff of capillaries, part of water and solutes filtered from blood, filtered fluid passes through tubular component to urine

Question 5

Tubular Component

Answer 5

Bowman’s capsule, Proximal tubule, Loop of Henle, Distal tubule, collecting duct

Question 6

Bowman’s Capsule

Answer 6

Cups around glomerulus

Question 7

Proximal tubule

Answer 7

Renal cortex, highly coiled or convoluted

Question 8

Loop of Henle

Answer 8

U-shaped, cortex and medulla, descending and ascending loops, passes between afferent and efferent arterioles, tubules and vascular=juxtaglomerular apparatus

Question 9

Distal tubule

Answer 9

Cortex, tightly coiled

Question 10

Renal Processes

Answer 10

Glomerular filtration, Tubular reabsorption, Tubular secretion (all involved in making urine)

Question 11

Glomerular Filtration

Answer 11

Capillaries very permeable except to plasma proteins, podocytes in Bowman’s capsule encircle (filtration slits), filtered fluid like plasma w/o proteins

Question 12

Filtration Driving Forces

Answer 12

*BP (hydrostatic P) in glomerular capillaries; plasma colloid osmotic P (unequal distribution of proteins across membrane) drives H2O back into blood and opposes BP; Bowman’s capsule hydrostatic P drives H2O out and opposes BP

Question 13

GFR

Answer 13

How well kidneys function; BP favors (55mmHg), Osmotic and hydrostatic P oppose (45mmHg), Net-10mmHg

Question 14

Tubular Reabsorption

Answer 14

Transepithelial transport (cross 5 barriers); Passive-moves down electrochemical or osmotic gradient; Active-nrg req, from lumen to plasma against electrochemical gradient (gluc, aa, Na, phosphate)

Question 15

Reabsorption Driving Forces

Answer 15

Na-K ATPase Pump needed for Na reabsorption

Question 16

Na Reabsorption-Proximal tube

Answer 16

Reabsorb glu, aa, H2O, Cl, urea; linked to K secretion

Question 17

Na Reab.-Loop of Henle

Answer 17

Along w Cl reab-critical ability to concentrate urine

Question 18

Na Reab-Distal and Collecting Ducts

Answer 18

Regulates ECF volume (BP)

Question 19

Aldosterone

Answer 19

Stimulates Na reab in distal and collecting ducts; depends on Na load in body; too much, little reab

Question 20

Renin-Angiotensin-Aldosterone

Answer 20

Dec in NaC, ECF vol, BP-juxtaglomerular apparatus secretes renin-angiotensin (plasma)-angiotensin I-angiotensin II (ACE in lung)-aldosterone (adrenal cortex)

Question 21

Atrial Natriuretic Peptide

Answer 21

Inhibits Na reab distal parts of nephron; when cardiac muscles in atria stretched, release ANP and BNP; Inc ECF vol stretches cardiac muscles

Question 22

Tubular Secretion

Answer 22

Transfer of materials from blood into lumen; H secretion impt in acid-base balance; K moves in different directions in different parts of tubule; Regulated by aldosterone (inc Na reab, inc K sec, inappropriate loss of K w dec ECF or dec BP)

Question 23

K Regulation

Answer 23

Key role in membrane electrical activity of excitable tissues; both inc and dec K concn can change membrane potential; cardiac excitability-dysrhythmia

Question 24

Plasma Clearance

Answer 24

Vol of plasma cleared of particular substance per min

Question 25

Creatinine Clearance

Answer 25

End product of muscle metabolism, freely filtered and not reabsorbed, rough estimate of GFR

Question 26

Vasopressin

Answer 26

ADH; For H2O sec across tubule (osmotic gradient, tubular segment must be permeable); Distal and collecting impermeable except in presence of ADH; Stored in post pituitary; Negative feedback

Question 27

Causes of Renal Failure

Answer 27

Infections, toxins, inappropriate immune response, obstruction to urinary flow, insufficient renal supply; lots of consequences