Excretory

Question 1

Classification of animals based on chief excretory product

Answer 1

Ammonotelic - Requires more water. Highly toxic. Marine animals, crustaceans, tadpole larva, aquatic insects

Ureotelic - Less water and less toxic. Terrestrial animals. Osmoconformer animals like Marine elasmobranch fish

Uricoltelic - uric acid as solid crystals. Birds, land snails, reptiles

Aminotelic- Unio and all echinoderms

Question 2

What is the position of the kidneys

Answer 2

Either side of vertebrae at the level of T12, L1 and L2.
Dorsal surface attached to dorsal abdominal wall. Ventral surface covered by peritoneum
Lie outside the coelom. Retroperitoneal
Renal capsule made of tough fibrous connective tissue

Question 3

What are the renal columns of Bertini

Answer 3

8-15 pyramidal structures formed by the cortical tissue projections in the renal medulla

Question 4

What is the trigone

Answer 4

The three openings ( 2 ureters and 1 urethral) form this triangular area.

Urethral opening- 2 sphincters, internal (smooth muscles ) and external( striated muscles)

Ureter opening guarded by mucosal flaps.

Question 5

Define structure of Bowman’s capsule

Answer 5

Outer simple squamous epithelium

Inner invaginated structure is made of cells called podocytes with protoplasmic projections and minute pores.

Question 6

Functions of pct

Answer 6

Highly convoluted to reduce speed of filtrate and increase surface area.
Lined with brush border cuboidal epithelium with mitochondria which provide energy for active transport of salts

Question 7

What is duct of Bellini

Answer 7

Collecting tubules of various nephrons- collecting duct in the renal medulla- these join together to form the large duct. Opens at papilla of pyramid

Question 8

Two types of nephrons

Answer 8

Cortical

Juxtamedullary

Question 9

Name the three pressures in ultrafiltration

Answer 9

Glomerular hydrostatic pressure
Colloidal osmotic pressure
Capsular hydrostatic pressure

Question 10

What is active tubular secretion

Answer 10

Movement of substances from the peritubular capillary network to the lumen of nephron.

Question 11

Functions of kidneys

Answer 11

RBC production by releasing erythropoietin when oxygen concentration is reduced

Osmoregulation

Regulates salt balance and pH and bloos pressure

Homeostatis

Secretion of renin

Question 12

Causes of acute renal failure

Answer 12

Acute nephritis

Lack of blood supply due to circulatory shock

Poisoning due to lead mercury and ccl4

Fall in bp due to haemorrhage, diahrrea, cholera

Renal calculi