Which one is surrounded by callose wall
1. Male gamete
2. Pollen grain
3. Egg
4. Microspore mother cell

Male gametophyte in angiosperms produces:
1. Single sperm and a vegetative cell
2. Single sperm and two vegetative cells
3. Three sperms
4. Two sperms and a vegetative cell

Pollen tablets are available in the market for:
1. In vitro fertilization
2. Breeding programmes
3. Supplementing food
4. Ex situ conservation

Function of filiform apparutus is to :
1. Recognize the suitable pollen at stigma
2. Stimulate division of generative cell
3. Produce nectar
4. Guide the entry of pollen tube

Which one of the following statements is correct?
1. Sporogenous tissue is haploid
2. Endothecium produces the microspores
3. Tapetum nourishes the developing pollen
4. Hard outer layer of pollen is called intine

Which one of the following is resistant to enzyme action
1. Pollen exine
2. Leaf cuticle
3. Cork
4. Wood fibre

Pollen grains can be stored for several years in liquid nitrogen having a temperature of        
1. - 196$°$C
2. - 80$°$C
3. - 120$°$C
4. - 160$°$C 

Filiform apparatus is characteristic feature of:
1. Nucellar embryo
2. Aleurone cell
3. Synergids
4. Generative cell