Unit 6 Urine and Acid Base System

Question 1

Major Functions

Answer 1

1. Excretion of waste products from blood
2. Convservation of blood nutrients
3. regulation of blood ion levels
4. Regulation of blood pH
5. Regulation of blood volume, BP
6. Production of hormones into the blood

Question 2

Glomerular hydrostatic P

Answer 2

GHP - 50 mmHg

- pushes water and small solutes out via fenestrated capillaries and filtration slits

Question 3

Capsular hydrostatic P

Answer 3

CsHP - 15 mmHg

- pushes water and small solutes back into the blood

Question 4

Net hydrostatic P

Answer 4

NHP: GHP-CsHP

50 - 13 = 35

Question 5

Blood colloid osmotic P

Answer 5

BCOP - 25 mmHg

- pulls the water back into the blood it opposes filtration

Question 6

Filtration P

Answer 6

FP: NHP - BCOP

35 - 25 = 10

Question 7

Creatine clearance rate

Answer 7

decent index used ?????

Question 8

ANP - Hormones

BNP - Hormones

Answer 8

Atria natriuretic peptides - released by atria of heart
Brain natriuretic peptide - released by ventricles of heart

• released when increased blood volume or blood pressure stretches the wall of the heart
• increase in stretch leads to afferent VD& efferent VC which leads to increase in GFR
• also leads to a decrease in Na+ reabsorption which leads to increase loss of Na+ and H2O

Question 9

Renin-andiotensin-aldosterone RAA

Answer 9

Renin is released from the juxtaglomerular complex which in turn increases GFR

Question 10

Hormone

Answer 10

a compound that is secreted by one cell and that travels through he blood stream to affect the activities of cells in another portion of the body

Question 11

enzyme

Answer 11

a protein that catalyzes a specific biochemical reaction

Question 12

Three things that trigger the release of renin

Answer 12

1. Low glomerular BP
2. SNS stimulation of juxtaglomerulus cells
3. Low osmolarity at macula dense

Question 13

Angiotensinogen

Answer 13

renin converts the inactive protein antiotensinogen to AT1; AT1 is also inactive but is then converted to angiotensin 2 by converting enzyme called ACE (conversion takes place in capillaries of the lungs

Question 14

AT2

Answer 14

triggers increased aldosterone (ALDO) secretion by the adrenal glands with increases Na+ retention

-efferent VC, thirst, SNS, ADH (anti-diurectic hormone) makes you not pee so you can retain water.

Question 15

Cotransport

Answer 15

both in the same direction; follows the gradient for 1 solute

Question 16

Countertransport

Answer 16

follows the gradient for 1 solute; solutes travel in opposite directions

-specific, unidirectional, variable distribution, heterogenous distribution, saturable

Question 17

Transport maximum (Tm)

Answer 17

substance the saturates carrier capacity - highest load you can handle and absorb

Question 18

Renal threshold

Answer 18

plasma gradient at which compound starts to appear in the urine; varies by compound

Question 19

countercurrent

Answer 19

exchange occurs between fluids moving in opposite directions - occurs in the loop of henle
- significant reabsorption of remaining water Na+, CL-

Question 20

multiplier

Answer 20

effect of exchange amplified as fluid movement continues - occurs in the loop of hence
- significant reabsorption of remaining water Na+, CL-

Question 21

2 Major benefits of countercurrent multiplier system

Answer 21

• efficiently reabsorbs solutes, water before fluid reaches DCT, collecting ducts
• establishes [ ] gradient that permits passive reabsorption of water from collecting ducts

Question 22

Anti - diuretic hormone (ADH)

Answer 22

From pituitary gland

• stimulates aquaporin production
• permits/promotes water reabsorption
• low levels of ADH at normal rest

Dehydration increases ADH secretion - absorb lots of water
EtOH inhibits ADH secretion - you dehydrate quickly

Question 23

aquaporin

Answer 23

water channels