How do lungs help in excretion?

1

(a)

Carbon dioxide and water are the waste products removed by the lungs in the expired air

What is the ratio of the concentrated filtrate to that of the initial filtrate?

1

(a)

The concentrated urine(filtrate) is nearly four times concentrated than the initial filtrate formed.

What will be the effect on the amount of urine released when water is abundant in the body tissues in case of vertebrates?

1

(a)

Vertebrates excrete large quantities of dilute urine when water is abundant in the body tissues and vice-versa.

Write the mode of excretion performed by Xenopus.

1

(a)

Dual excretion (mainly ammonotelism and partly ureotelism).

Give the name of cells that are responsible for the formation of filtration slits or slit pores.

1

(a)

Podocytes (epithelial cells present in the inner wall of Bowman's capsule).

Give the name of the main components that play an important role in the counter-current mechanism.

1

(a)

Henle's loop and vasa recta

Give the name of the nitrogenous waste which is produced in birds.In what form is it eliminated from the body?What is the advantage of this type of excretion?

1

(a)

Birds excrete uric acid in the form of pellet or paste (semi-solid form). It helps is conservation of water.

What stimulates the release of aldosterone? How does aldosterone increase the blood pressure and regulate GFR?

1

(a)

Angiotensin-II

What is stimulus for the cells of JGA to release renin?

1

(a)

Glomerular blood pressure falls.

Why tubular secretion an important step in urine formation?

1

(a)

maintains ionic balance and pH of body fluids.