List of practice Questions

LCM of the numbers 12 and 20 will be :

During PCR, primers bind to the DNA strands in the __________ step.

Natural selection can lead to
(a) stabilisation
(b) genetic drift
(c) directional change
(d) disruption
Choose the correct answer from the options given below :

Which of the following statements are correct?
(a) Energy flow from producers to consumers is unidirectional
(b) Energy pyramid can never be inverted
(c) Transfer of energy follows the 1% law
Choose the correct answer from the options given below :

Which of the following are primary consumers in a food chain ?

Which of the following statements about the reabsorption process in Henle's loop are correct ?
(a) The descending limb of Henle's loop is permeable to water but almost impermeable to electrolytes.
(b) Urine gets concentrated in Henle's loop.
(c) Reabsorption of \(\text{Na}^+\) and water takes place in Henle's loop.
(d) Active or passive transport of electrolytes occurs in the ascending limb of Henle's loop.
Choose the correct answer from the options given below :

Which of the following is the correct order of arrangement of vertebrate column from the head to toe ?

If the diploid chromosome number of typical angiosperm is 36, what would be the chromosome number in its endosperm ?

Which of the following enzymes synthesizes precursor mRNA ?

Sperm motility is due to __________.

Consider a population of 10 million cells. Given the per-capita birth rate of 0.002 (per unit time) and the per-capita death rate of 0.002 (per unit time), the expected number of cells after 10 generations is __________.

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Forelimbs of human and bats are homologous.
Reason R: Forelimbs of humans and bats have similar anatomical structure.
In the light of the above statements, choose the most appropriate answer from the options given below:

Muscle contraction is initiated by a signal sent by the central nervous system by the release of __________.

Which of the following hormone is not secreted by human placenta ?

Which of the following statements is correct about Plasmodium ?

Colostrum, secreted by mother during initial days of lactation, is abundant in

Which of the following disease is not sexually transmitted ?

Which of the following statements about lac-operon is correct ?

A population of diploid organisms is at Hardy-Weinberg equilibrium. If the frequency of allele A is 0.1, the frequency of AA is

Which of the following is used as a clot buster ?

Which of the following structure is not a part of the male reproductive system ?

Given below are two statements:
Statement I: Ovulation is caused by LH surge leading to rupture of Graafian follicles.
Statement II: Graafian follicle remaining after ovulation transform into corpus luteum and secretes large amount of estrogen.
In the light of the above statements, choose the most appropriate answer from the options given below:

The opening between the right atrium and the right ventricle is guarded by

Which of the following is not evidence for evolution ?

The inactive form of Bt toxin is converted to the active form in the insect gut