which of the following characteristics that are involved to enhances the survival and reproduction of organisms that bear it ?

TLS Online TPP Program

#Question id: 34161

#Unit 7. System Physiology – Animal

Congenital defects in the enzymes lead to deficient cortisol secretion and the syndrome of congenital adrenal hyperplasia. A cause of severe congenital adrenal hyperplasia in newborns is a loss of function mutation of the gene for the: 

TLS Online TPP Program

#Question id: 34162

#Unit 7. System Physiology – Animal

Gonadal and adrenocortical steroids are of following types, EXCEPT? 

TLS Online TPP Program

#Question id: 34163

#Unit 7. System Physiology – Animal

Which of the following represents the correct sequential pathway for aldosterone synthesis from cholesterol, based on the enzyme-catalyzed steps?

TLS Online TPP Program

#Question id: 34164

#Unit 7. System Physiology – Animal

A newborn is diagnosed with 21β-hydroxylase deficiency. Which of the following downstream consequences is most likely due to impaired glucocorticoid production during fetal life?

TLS Online TPP Program

#Question id: 34165

#Unit 7. System Physiology – Animal

Following statements are regarding thyroid hormone biosynthesis?

I. The basolateral membranes of thyrocytes facing the capillaries contain a antiporter that transports two Na⁺ ions and one I^– ion into the cell with each cycle, against the electrochemical gradient for I^–.

II. Na⁺/I^– symporter (NIS) is capable of producing intracellular I^– concentrations that are 20–40 times as great as the concentration in plasma.

III. TSH induces both NIS expression and the retention of NIS in the basolateral membrane, where it can mediate sustained iodide uptake.

TLS Online TPP Program

#Question id: 34166

#Unit 7. System Physiology – Animal

I. Adrenocortical secretion is controlled primarily by ACTH, from the anterior pituitary, but mineralocorticoid secretion is also subject to independent control by circulating factors.

II. Adrenal medullary hormones work mostly to prepare the body for emergencies, the so-called “fight-or-flight” responses.

III. All three cortical zones secrete corticosterone, but the active enzymatic mechanism for aldosterone biosynthesis is not limited to the zona glomerulosa.

IV. An important function of the zona glomerulosa, in addition to aldosterone synthesis, is the formation of new cortical cells.