Urinary System

Question 1

Parts of kidneys (5)

Answer 1

Medulla (circular structures which intertubluar BVs go around), Cortex, Renal sinus (space), intertubular veins + arteries, ureter (connect kidneys to bladder)

Question 2

movement within calyx and medulla

Answer 2

Gloymeylus (bowman’s capsule)-> proximal convoluted tubule-> descencing limb-> loop of henle-> ascending limb-> distal convoluted tubule-> collecting duct

Question 3

What does the glomerulus do?

Answer 3

filter blood leaving only plasma

Question 4

What occurs in the proximal convoluted tube, descening limb and loop of henle?

Answer 4

reabsorption of water and solutes which helps produce concertrated urine

Question 5

what occurs at ascending limb?

Answer 5

further solutes reabsorped

Question 6

what occurs in distal convoluted tubule and collecting duct?

Answer 6

hormones control more reabsorption of water and solutes

Question 7

BVs serving kidneys

Answer 7

renal artery, renal vein

Question 8

overview of filtration process / urine production (3)

Answer 8

1. Filtration: all blood (except plasma) and some proteins exit at glomrular cappilaries and enter at bowman’s capsule, autoregulated
2. Tubular Reabsorption: return of water and solutes to blood via renal BVc which removes toxins and maintains hydration, can be active or passive
3. Movement of non-filtered substances from blood and be filtered further, can be active or passive

Question 9

Roles of kidneys (6)

Answer 9

1. Excretion: removing toxins, excess ions and metabolic waste from blood
2. Regulate BP & vol: control extr-celluar fluid volume regulating blood volume by how much urine is produced
3. Regulation of VitD level: control level of blood Ca++ which activates vit D
4. Regulates solute (ion) conc in blood
5. Regulate extracellular fluid pH: by varying amount of H+ lost
6. Control rate of RBC production: via secretion of erythropoietin hormone which stimulates bone marrow

Question 10

Mechanisms influencing kidney regulation

Answer 10

Renin-Angiotensin-Aldosterone Mechchanism :
renin production -> renin is transported to lungs where it acts with angiotensin to make angotensin 1 -> angiotensin-converting-enzyme (ACE) converts angotensin 1 to angiotensin 2 -> angiotensin 2 causes vasular contriction which increases BP causing aldosterone to be produced by adrenal gland -> aldosterone release will increase reabsorption of water into blood in kidneys, reducing urine level, so blood vol is increased and BP is increased.