Practice Questions

TLS Online TPP Program

#Question id: 7264

The Dictyostelia social amoebas are found in a wide range of soil habitats. They can come together to form a fruiting structure, in which a proportion of cells are sacrificed to build the stalk and the remainder differentiate into resilient dormant spores. This multicellular life cycle is common to all Dictyostelids. It consists of an interconnected programme of cell movement and cell differentiation, and has been intensively studied in the model organism D. discoideum. Few mutants (Column A) and phenotypes (Column B) are listed in the table given below.

Column A

Column B

A. Loss of function of cAMP-dependent protein kinase (PKA)

i. cell develop normally but unable to germinate

B. Loss of function of RegA

ii. Loose aggregate form

C. Loss of function of adenylate cyclase B

iii. No aggregation

D. Loss of function of gp80

iv. accumulation of cAMP and PKA activation

Match the correct mutant with the observed phenotype.

#Unit 5. Developmental Biology

A-iv, B-ii, C-iii, D-i
A-iv, B-iii, C-i, D-ii
A-ii, B-iii, C-iv, D-i
A-iii, B-iv, C-i, D-ii

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TLS Online TPP Program

#Question id: 20274

#Unit 7. System Physiology – Animal

ADH has two actions, one on the kidney and the other on vascular smooth muscle, these actions are mediated by different receptors, different intracellular mechanisms, and different secondary messengers.

a. The major action of ADH is to increase the water permeability of principal cells in the late distal tubule and collecting duct.

b. The receptor for ADH on the principal cells is a V2 receptor, which is coupled to adenylyl cyclase via a Gs protein.

c. The second messenger is cAMP, via phosphorylation steps, directs the insertion of water channels, aquaporin 2 (AQP2), in luminal membranes.

d. The receptor for ADH on the principal cells is a V1 receptor, which is coupled to phospholipase C via Gq protein.

Which one of the following combination of above statements is correct?

TLS Online TPP Program

#Question id: 20275

#Unit 7. System Physiology – Animal

Vasopressin has two actions, one on the kidney and the other on vascular smooth muscle, Contraction of vascular smooth muscle are mediated by different receptors, different intracellular mechanisms, and different second messengers,

a. The receptor for ADH on vascular smooth muscle is a V1 receptor

b. The receptor for ADH on the vascular smooth muscle is a V2 receptor

c. The second messenger for this action is IP3/Ca2+

d. The second messenger is cAMP.

Which of the above is/are correct?

TLS Online TPP Program

#Question id: 20276

#Unit 7. System Physiology – Animal

Central diabetes insipidus is caused by failure of the posterior pituitary to secrete ADH and the following statements pertain to that disorder:

A. excretion of large volumes of dilute urine

B. the urine cannot be concentrated

C. produces large volumes of dilute urine

D. increased serum osmolarity

E. circulating levels of ADH are high

Which of the following is the correct combination of the statements given above?

TLS Online TPP Program

#Question id: 20277

#Unit 7. System Physiology – Animal

Which is structurally similar to growth hormone?

d. Bromocriptine

Which of the above is/are correct?

TLS Online TPP Program

#Question id: 20278

#Unit 7. System Physiology – Animal

What type of protein is human growth hormone?

TLS Online TPP Program

#Question id: 20279

#Unit 7. System Physiology – Animal

Which one of the following statements is true with regard to Growth Hormone Secretion?

a. Growth hormone is secreted in a pulsatile pattern.

b. Growth hormone secretory rates are constant over a lifetime.

c. After puberty, the rate of growth hormone secretion declines to a stable level.

d. The highest rates of growth hormone secretion occur during puberty, and the lowest rates occur in senescence.

Which of the following is the correct combination of the statements given above?