Question

Read the given statements regarding the human excretory system and select the correct ones.
(i) Presence of glucose in urine is known as uremia.
(ii) Distal convoluted tubule (DCT) selectively secretes hydrogen ions, ammonia and potassium ions into the filtrate.
(iii) Macula densa formed bye cellular modifications in the distal convoluted tubule and the afferent arteriole at their contact location.
(iv) Atrial natriuretic factor (ANF) can cause vasoconstriction when blood flow is low to the atria of the heart.

• A. (i) and (ii)
• B. (i) and (iii)
• C. (ii) and (iii)
• D. (iii) and (iv)

Answer 1

The correct option is C (ii) and (iii)

$K^{+}$ , $H^{+}$ , $N{H}_3$ and $HC{O}_3$ ions are secreted by active transport into the filtrate in the DCT. Juxtaglomerular apparatus is a sensitive region formed by cellular modifications in the DCT and the afferent arteriole at their contact location. Juxtaglomerular apparatus consists of juxtaglomerular cells, macula densa and lacis cells. Presence of glucose in the urine is called glycosuria. ANF can cause vasodilation when blood flow is high to the atria of the heart.

So the correct answer is '(ii) and (iii)'.