The Renal System

Question 1

What is the function of the ureters?

Answer 1

Move urine to the bladder via peristalsis

Question 2

What is the bladder composed of?

Answer 2

Smooth Muscle

Question 3

How much fluid can the bladder hold?

Answer 3

400-600mL

but can hold double if necessary

Question 4

The urethra contains 2 sphincters. Name them and discuss the type of muscle they are composed of.

Answer 4

INTERNAL URETHRAL SPHINCTER:
Smooth muscle - autonomic

EXTERNAL URETHRAL SPHINCTER:
Skeletal muscle - voluntary

BOTH MUST BE RELAXED FOR URINE TO BE EXPELLED

Question 5

Name the 3 layers of the Adrenal Cortex

Answer 5

Zona glomerulosa
Zona fasciculata
Zona reticularis

Question 6

What hormone(s) does the zona glomerulosa produce?

Answer 6

Aldosterone

Question 7

What hormone(s) does the zona fasciculata produce?

Answer 7

Cortisol

Question 8

What hormone(s) does the zona reticularis produce?

Answer 8

Sex Hormones

DHEA, progesterone, oestrogen, testosterone

Question 9

What is produced by the Adrenal Medulla?

Answer 9

Catecholamines

adrenaline & noradrenaline

Question 10

Give the dimensions of a standard kidney

Answer 10

10 cm LONG
5.5 cm WIDE
3 cm THICK

Question 11

Provide some examples of what the kidney controls

Answer 11

WHOLE BODY HOMEOSTASIS

• salt & H20
• acid
• blood P
• removal of by-products, toxins, drugs

Question 12

Why is the kidney also considered an endocrine gland?

Answer 12

Secretes renin
(regulates blood pressure [with other substances])

Produces erythropoietin
(stimulates red blood cell production)

Regulates Vit. D activation & deactivation

Question 13

What is the function of the nephron?

Answer 13

• Filtrates plasma
• Concentrates urine
• Removes toxins & by-products

Question 14

Name the 2 COMPONENTS of the nephron.

Answer 14

Tubular

Vascular
efferent arteriole becomes peritubular capillaries

Question 15

What at the 3 FUNCTIONS of the nephron?

Answer 15

(Glomerular) Filtration

(Tubular) Reabsorption

(Tubular) Secretion

Question 16

What is the function of Juxtaglomerular Granular Cells (and where are they located)?

Answer 16

Synthesises, Stores & Secretes RENIN
(renin secretion in response to):
 -low blood P
 -low NaCl in tubules
 -SNS innervation

Location: Butts up against Macula Densa (afferent arteriole)

Question 17

What is the function of RENIN?

Answer 17

Increase conversion of Angiotensinogen to Angiotensin 1

Angiotensin 1 converted into Angiotensin 2
(by ACE in lung)
ACE is a strong vasoconstrictor;
thus increases Aldosterone release from Adrenal Gland

Both lead to INCREASE BLOOD P.

Question 18

When are symptoms of Chronic Renal Failure (CRF) noticeable?

Answer 18

When only 10-20% kidney function is left

CRF can affects EVERY ORGAN SYSTEM
i.e. neurological syst., GI syst. etc.