List of practice Questions

Consider an endothermic reaction $X\, \to \,Y$ with the activation energies $E_b$ and $E_f$ for the backward and forward reactions respectively. In general :
The rate constant of a reaction depends on:
The temperature coefficient of a reaction is 2. If the velocity of the reaction is 5 at 25�C, then, the velocity of the reaction at 55�C is
If $2.0 \,g$ of a radioactive isotope has a half-life of $20\, h$, the half-life of $0.25 \,g$ of the same substance is:
If $\sin A , \sin B , \cos A$ are in GP, then roots of $x ^{2}+2 x \cot B +1=0$ are always
In Chlamydomonas the meiosis occurs in :
Negatively geotropic roots are found in
Algae which form motile colony is
First vascular plant group is
Which pteridophyte is called horse-tail ?
Dominant generation in bryophytes is
Selaginella leaf possesses an adaxial out growth proximally
Having capacity of absorbing water, used to replace cotton and used as fuel
The edible dry fruit 'Chilgoza' is
Pteridophytes are also called
The integument of Cycas ovule is hard on account of
To which of the groups would you assign plant lacks ovules and reproduces by means of spores ?
A typical gymnospermous plant has 8 chromosomes in leaf cells. What will be number of chromosomes in the cells of the gametophyte ?
The pigment phycoerythrin is characteristic of
During fertilization in ferns, male gamete reaches the female gamete through the agency of
Fucoxanthin is present in
In gymnosperms how many male gametes are produced by each pollen grain ?
Which of the following is known as `resurrection plant??
Most primitive members in which roots are not present, is :
Law of multiple proportions is illustrated by one of the following pairs: