Cytokinins

1. Cytokinins are

a) adenine derivatives

b) guanine derivatives

c) cytidine derivatives

d) thymine derivatives

2. Which of the following is a natural cytokinin

a) isopentanyl adenine

b) zeatin

c) 6-isopentanyl aenine

d) 6-amino purine

3. The first kinetin isolated by Miller was from

a) coconut endosperm

b) maize grains

c) herring sperm DNA

d) wheat grains

4. The first natural cytokinin isolated from liquid endosperm was

a) isopentanyl adenine

b) zeatin

c) 6-isopentanyl aenine

d) 6-amino purine

5. Agrobacterium tumefaciens Ti plasmids t-DNA has genes for

a) Auxin and giberrellins

b) cytokinins and ethylene

c) cytokinins and giberrellins

d) Auxin and cytokinins

6. Which of the following is the precursor of cytokinins

a) adenine

b) guanine

c) cytidine

d) thymine

7. Cytokinins are predominantly present in

a) permanent tissues

b) meristamatic tissues

c) endodermis

d) cortical region

8. All are bioassays for cytokinins except

a) chlorophyll preservation test

b) tobacco pith culture

c) rice seedling growth inhibition test

d) excised radish cotyledon enlargement test

9. All the statement are true regarding cytokinin except

a) promote cell division

b) delay senescence

c) induce dormancy

d) counteract apical dominance

10. Cytokinin treatment enhances

a) chlorophyll synthesis

b) chlorophyll degradation

c) protein degradation

d) water uptake

11. In tissue culture, high cytokinins to auxin ratio causes

Cytokinin: Auxin ratio

Cytokinin: Auxin ratio

a) root differentiation

b) shoot differentiation

c) both a and b

d) none of these

12. In tissue culture, low cytokinins to auxin ratio causes

a) root differentiation

b) shoot differentiation

c) both a and b

d) none of these

13. Translocation of cytokinin is polar and takes place through

a) xylem

b) phloem

c) both phloem and xylem

d) capillary rise

14. ‘Pomalin’ is effective in increasing apple size and is a combination of

a) Auxin and giberrellins

b) cytokinins and ethylene

c) cytokinins and giberrellins

d) Auxin and cytokinins

15. Which of the following hormone is involved in counteracting apical dominance induced by

auxin

a) cytokinin

b) ethylene

c) abscisic acid

d) brassinosteroids

Answers
1-a6-a11-b
2-b7-b12-a
3-c8-c13-a
4-b9-c14-c
5-d10-a15-a