Which form of nitrogenous waste is most toxic and requires maximum water for elimination?

Ammonia

True or False: Uric acid can be removed with minimal water loss.

True

Animals that excrete ammonia are called _____.

Ammonotelic animals

What are the excretory structures found in Platyhelminthes called?
A) Nephridia
B) Protonephridia
C) Malpighian tubules
D) Green glands

B) Protonephridia

Why do marine fish excrete urea instead of ammonia?

Urea is less toxic and conserves water in marine environment

Which animals have Malpighian tubules as excretory structures?

Insects like cockroaches

True or False: Kidneys play a significant role in ammonia removal in bony fishes.

False. Ammonia is excreted through gill surfaces by diffusion

What is the functional unit of kidney called?

Nephron

The cup-shaped structure that encloses glomerulus is called _____.

Bowman's capsule

How many nephrons are present in each human kidney approximately?
A) 500,000
B) 1 million
C) 2 million
D) 10 million

B) 1 million

What happens when loop of Henle extends deep into medulla?

Forms juxtamedullary nephrons which concentrate urine better

Which process involves filtering blood through three layers in kidney?

Glomerular filtration

True or False: Podocytes are epithelial cells of glomerular blood vessels.

False. Podocytes are epithelial cells of Bowman's capsule

Normal GFR in healthy individual is _____ ml/minute.

125

What does JGA release when GFR decreases?
A) ADH
B) Aldosterone
C) Renin
D) ANF

C) Renin

Why is only 1.5 liters urine excreted when 180 liters filtrate is formed?

99% of filtrate is reabsorbed by renal tubules

Which segment reabsorbs 70-80% of electrolytes and water?

Proximal convoluted tubule (PCT)

True or False: Descending limb of Henle's loop is impermeable to water.

False. It is permeable to water but impermeable to electrolytes

The countercurrent mechanism helps maintain osmolarity gradient from _____ to _____ mOsmolL⁻¹.

300 (cortex) to 1200 (inner medulla)

Which hormone facilitates water reabsorption from latter parts of renal tubule?
A) Renin
B) Aldosterone
C) ADH
D) ANF

C) ADH

What triggers release of ANF from heart atria?

Increased blood flow to atria

The neural mechanism controlling urine release is called _____.

Micturition reflex

True or False: Presence of glucose in urine indicates diabetes mellitus.

True

During hemodialysis, why is heparin added to blood?
A) To increase filtration
B) To prevent clotting
C) To remove toxins
D) To maintain pH

B) To prevent clotting