Renal Anatomy and Physiology

Question 1

what is the urinary system made up of?

Answer 1

2 kidneys, 2 ureters, a bladder and a urethra.

The kidneys produce urine which is transported by the ureters to the bladder to be stored and then excreted from the body via the urethra.

Question 2

What is the functional units of the kidney?

Answer 2

nephrons

The nephron is composed of
the glomerulus (tangled cluster of capillaries surrounded by the Bowman’s capsule) and the tubules.

Question 3

Blood enters the kidneys through the _______.

Answer 3

renal artery

The artery eventually branches off into capillaries.

Kidneys are important in maintaining good health because they filter fluid, wastes, & extra electrolytes from the capillaries into the tubules.

Question 4

The amount of urine produced is partially affected by the __________.

Answer 4

antidiuretic hormone (ADH).

This hormone affects the healthy kidney by reducing the excretion of urine.

Question 5

What are the 4 functions of the kidney?

Answer 5

Excretory:
Regulatory:
Filtration:
Endocrine:

Question 6

Excretory:

Answer 6

kidneys rid the body of waste products and excess fluid and electrolytes.

When waste products build up in the blood it is called uremia.

If waste products are not removed, it adversely affects every system of the body.

Question 7

Regulatory:

Answer 7

kidneys maintain acid/base balance (done by excreting H+ and reabsorbing bicarbonate), fluid balance and electrolyte balance.

Each electrolyte must be kept within a certain range in order for the body to function correctly.

Electrolytes send impulses along the nerves to muscles – for instance high potassium (hyperkalemia) causes muscle weakness and cardiac arrhythmias, possibly leading to heart attack and death.

So it’s important that electrolytes be kept within certain ranges. This balance is called homeostasis.

Question 8

Filtration:

Answer 8

nephrons retain some things and filter out and reabsorb others.

Question 9

Endocrine:

Answer 9

Kidneys produce several Hormones including renin , erythropoietin, the kidneys also convert the storage form of Vitamin D to its active form (Calcitriol). Active vitamin D is needed to absorb calcium from the gut.

Without it bones become weak and brittle (renal osteodrystrophy).

Hormone production cannot be replaced by dialysis.

Question 10

renin

Answer 10

which constricts blood vessels resulting in increasing BP

Question 11

erythropoietin

Answer 11

which signal bone marrow to produce RBCs

(lack of this hormone is the major reason End Stage Renal Disease {ESRD} patients are anemic);