A metal is irradiated with light of wavelength 660 nm. Given that the work that the work function of the metal is
1.0 eV, the de Broglie wavelength of the ejected electron is close to
In the DNA of E. Coli the mole ratio of adenine to cytosine is 0.7. If the number of moles of adenine in the DNA is
350000, the number of moles of guanine is equal to –
(A) 350000 (B) 500000 (C) 225000 (D) 700000
A reflex action is a quick involuntary response to stimulus. Which of the following is an example of BOTH,
unconditioned and conditioned reflex ?
(A) knee Jerk reflex (B) secretion of saliva in response to the aroma of food
(C) sneezing reflex (D) contraction of the pupil in response to bright light
In Dengue virus infection, patients often develop haemorrhagic fever due to internal bleeding. This happens due to
the reduction of –
(A) platelets (B) RBCs (C) WBCs (D) lymphocytes
Vitamin A deficiency leads to night-blindness. Which of the following is the reason for the disease ?
(A) rod cells are not converted to cone cells
(B) rhodopsin pigment of rod cells is defective
(C) melanin pigment is not synthesized in cone cells
A hormone molecule binds to a specific protein on the plasma membrane inducing a signal. The protein it binds to
is called –
(A) ligand (B) antibody (C) receptor (D) histone
Which of the following is true for TCA cycle in eukaryotes ?
(A) takes place in mitochondrion (B) produces no ATP
(C) takes place in golgi complex (D) independent of electron transport chain
By which of the following mechanisms is glucose reabsorbed from the glomerular filtrate by the kidney tubule ?
(A) osmosis (B) diffusion (C) active transport (D) passive transport
Human chromosomes undergo structural changes during the cell cycle. Chromosomal structure can be best
visualized if a chromosome is isolated from a cell at –
(A) G1 phase (B) S phase (C) G2 phase (D) M phase
Some animals excrete uric acid in urine (uricotelic) as it requires very little water. This is an adaptation to conserve
water loss. Which animals among the following are most likely to be uricotelic ?
(A) fishes (B) amphibians (C) birds (D) mammals