Multiple Choice Questions

Advertisement

What is the effect of GnRH produced by hypothalamus?

  • Stimulates the synthesis and secretion of androgens

  • Stimulates secretion of milk in mammary glands

  • Stimulates foetal ejection reflex

  • Stimulates synthesis of carbohydrates from non- carbohydrates in liver


A.

Stimulates the synthesis and secretion of androgens

Gonadotropin Releasing Hormone (GnRH) is a releasing hormone. It stimulates the anterior lobe of the pituitary gland to secrete two gonadotropic hormones- FSH (Follicle Stimulating Hormone) and LH (Luteinising Hormone). 

In males, LH stimulates testosterone production from the interstitial cells of the testes (leydig cells). FSH stimulates testicular growth and enhances the production of an androgen- binding protein by the Sertoli cells, which are a component of the testicular tubule necessary for sustaining the maturing sperm cells.

In females, FSH stimulates the growth of ovarian follicles in the ovary before the release of an egg from one follicle at ovulation. It also increases oestradiol production. LH triggers ovulation and development of the corpus luteum.


Advertisement

Chemosensitive area of respiratory centre in medulla is affected by

  • less CO2 and H+ ions

  • less O2 and Hions

  • excess CO2 and H+ ions

  • excess O2 and Hions


Cyclic photophosphorylation involves

  • PS I

  • PS II

  • PS I and PS II

  • P680


The taxon which includes related species is

  • class

  • order

  • family

  • genus


The type of epithelial cells which line the inner surface of Fallopian tubes, bronchioles and bronchi are known as

  • squamous epithelium

  • ciliated epithelium

  • columnar epithelium

  • cubical epithelium


Advertisement

Animals take phosphorus from

  • water

  • plants

  • rock

  • soil


Which one is correct regarding electrocardiograph (ECG)?

  • P- wave represents the electrical excitation of the ventricle.

  • QRS complex represents repolarisation of the ventricles

  • T- wave represents repolarisation of the atria

  • By counting the number of QRS complexes one can determine the pulse rate


Which of the following have porous body and are diploblastic?

  • Aurelia and Obelia

  • Adamsia and Euplectella

  • Leucosolenia and Spongilla

  • Sycon and Hydra


Microvilli of intestinal epithelium are similar in function with 

  • typhlosole in earthworm

  • hepatic caecae in cockroach

  • intestinal caecum in earthworm

  • Malpighian tubules in coackroach


Advertisement

What are Singer and Nicolson known for?

  • One-gene-one-enzyme hypothesis

  • Plasma membrane modifications

  • Fluid-mosaic model of plasma membrane

  • Structure of DNA