List of practice Questions

Identify the correct combination.
A. Agrobacterium tumefaciens – vector for transgenic plant.
B. Escherichia coli – selectable marker.
C.Thermus aquaticus – Taq polymerase.
D.Bacillus thuringiensis – BT. Toxin.

The introduction of nematode-specific genes into host using Agrobacterium vectors causes the following action:
I. Formation of dsRNA.
II. Production of sense and antisense RNAs in the host cells.
III. RNA intermediate not formed.
IV. Silencing of specific mRNA of the nematode.

Assertion (A): Trichoderma polysporum produces cyclosporin A, an immunosuppressive agent.
Reason (R): It is used in organ transplant patients.

Assertion (A): Epidermis of hydrophytes is useful for absorption and assimilation.
Reason (R): In hydrophytes, epidermal cells are devoid of cuticle and contain chloroplasts.

Assertion (A): Beggiatoa changes its shape.
Reason (R): Some bacteria change their shapes depending upon the type of environment.

Assertion (A): Loss or gain of a segment of DNA results in alteration in chromosomes.
Reason (R): Alterations in chromosomes do not result in abnormalities.

Genotype of dominant trait of plant can be determined by crossing $F_{1}$ hybrid with the parent and the genotypic ratio is

Give the nucleotide sequence in the mRNA for this sequence of amino acids given below
Met – Phe – Arg – Gly – Phe

In the above reaction, a and b are
$2NH_{3} + 3O_{2}$ → a + $2NO_{2} + O_{2}$ → b → $2NO_{3}$

Choose the correct statements
a. Inability of seed germination due to immature embryo is called Quiescence.
b. Seed coats of Fabaceae do not absorb $O_{2}$ and $H_{2}O$.
c. Germination of tomato seeds is inhibited by chemical compounds.
d. Seeds of polygonum require exposure to low temperature.

Arrange the following in a sequence in primary succession in water:
A: Sedges and grasses
B: Trees
C: Phytoplankton
D: Free floating plants