Which of the following has proved helpful in preserving pollens as fossils?

Pollen grains are able to withstand extremes of temperature and dessication because their exine is composed of

(1) cutin

(2) suberin

(3) sporopollenin

(4) callose

The pollen grains of rice and wheat lose their viability in ___ minutes of their release.

(1) 30

(2) 10

(3) 60

(4) 90

An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is

1. cuticle

2. sporopollenin

3. lignin

4. cellulose

The viability of pollen grains depends upon:
(1) Prevailing temperature

(2) Prevailing humidity

(3) Genetic potentiality of the concerned species

(4) All of the above

Which one of the following is resistant to enzyme action?

(1) Cork

(2) Wood fibre

(3) Pollen exine

(4) Leaf cuticle

Fossilization of pollen grains is helped by

(1) Compatible protein  

(2) Sporopollenin

(3) Cellulose

(4) Pectin

Which of the following has the least pollen viability?

(1) Cereals like wheat and rice          

(2) Members of Rosaceae

(3) Members of Leguminoseae           

(4) Members of Solanaceae

Pollen grains can be stored for several years in liquid nitrogen having a temperature of:

Which among the following is not true about pollen grain?

(1) Rich in nutrients.

(2) Many species cause severe allergies and bronchial afflictions in some people often leading to chronic respiratory disorders– asthma, bronchitis, etc.

(3) Pollen consumption has been claimed to increase the performance race horses.

(4) Parthenium is used against pollen allergy.