If a man with an X-linked dominant disease has six sons with a woman having a normal complement of
genes, then the sons will
(A) not show any symptoms of the disease
(B) show strong symptoms of the disease
(C) three will show a disease symptom, while three will not
(D) five will show a disease symptom, while one will not
Mendel showed that unit factors, now called alleles, exhibit a dominant/ recessive relationship. In a
monohybrid cross, the .................. trait disappears in the first filial generation
(A) dominant (B) co-dominant (C) recessive (D) semi-dominant
Vestigial organs such as the appendix exist because
(A) they had an important function during development which is not needed in the adult
(B) they have a redundant role to play if an organ with similar function fails
(C) nature cannot get rid of structures that have already formed
(D) they were inherited from an evolutionary ancestor in which they were functional
You remove four fresh tobacco leaves of similar size and age. Leave "leaf 1" as it is, smear "leaf 2" with
vaseline on the upper surface, "leaf 3" on the lower surface and "leaf 4" on both the surfaces. Hang the leaves
for a few hours and you observe that leaf 1 wilts the most, leaf 2 has wilted, leaf 3 wilted less than leaf 2 and
leaf 4 remains fresh. Which of the following conclusion is most logical ?
(A) tobacco leaf has more stomata on the upper surface
(B) tobacco leaf has more stomata on the lower surface
(C) stomata are equally distributed in upper and lower surfaces
(D) no conclusion on stomatal distribution can be drawn from this experiment
At 783 K in the reaction H2(g) + I2(g) 2HI (g), the molar concentrations (mol-1) of H2, I2 and HI at some instant of time are 0.1, 0.2 and 0.4, respectively. If the equilibrium constant is 46 at the same temperature, then as the reaction proceeds
option
(A) the amount of HI will increase
(B) the amount of HI will decrease
(C) the amount of H2 and I2 will increase
(D) the amount of H2 and I2 will not change
Among (i) [CO(NH3)6]Cl3, (ii) [Ni(NH3)6]Cl2, (iii) [Cr(H2O)6]Cl3, (iv) [Fe(H2O)6]Cl2 the complex which is diamagnetic is
option
(A) i
(B) ii
(C) iii
(D) iv
An aqueous buffer is prepared by adding 100 ml of 0.1 mol l-1 acetic acid to 50 ml of 0.2 mol l-1 of sodium acetate. If pKa of acetic acid is 4.76, the pH of the buffer is
option
(A) 4.26
(B) 5.76
(C) 3.76
(D) 4.76
A student sees the top edge and the bottom center C of a pool simultaneously from an angle i¸ above the horizontal as shown in the figure. The refraction index of water which fills up to the top edge of the pool is 4/3. If h/x = 7/4 then cos i¸ is
In a thermally isolated system, two boxes filled with an ideal gas are connected by a valve. When the valve is in closed position, states of the box 1 and 2, respectively, are (1 atm, V, T) and (0.5 atm, 4V, T). When the valve is opened, the final pressure of the system is approximately
option
(A) 0.5 atm
(B) 0.6 atm
(C) 0.75 atm
(D) 1.0 atm