top of page

POLLEN GRAIN

  • Study of Pollen is called Palynology.

  • Typical shape- Spherical

  • Size- 25-50 um (in diameter)

  • Pollen grain represents the male gametophyte i.e. it carries the male gametes to the female reproductive parts in Gymnosperms and Angiosperms.


STRUCTURE OF POLLEN

Structure of a Pollen Grain

1. POLLEN WALL
  • Pollen has a prominent two-layered wall i.e. Exine and Intine.

EXINE
  • Outermost protective layer of the pollen

  • Hard and thick layer

  • Discontinuous layer as exine has prominent apertures called Germ Pores

  • Exine exhibits fascinating array of patterns and designs

  • Made up of Sporopollenin (most resistant organic material known)

INTINE
  • Thin and elastic layer

  • Continuous layer

  • Made up of cellulose and pectin

2. CELLS
  • A mature pollen consist of two cells i.e. Vegetative cell and Generative cell

VEGETATIVE CELL
  • Large in size

  • Nucleus is large and irregularly shaped

  • Contains abundant food reserve

  • Fn- Helps in development of pollen tube

GENERATIVE CELL
  • Small in size

  • Floats in the cytoplasm of vegetative cell

  • Nucleus is Spindle shaped

  • Contains dense cytoplasm

  • Fn- Divides by mitosis to form two non-motile male gametes.


ADVANTAGES OF POLLEN


TO PLANTS
  • Carries male gametes to the female sex organ for fertilisation.

  • Enabled the higher plants (Gymnosperms and Angiosperms) to grow in a wide range of terrestrial habitat as pollen eliminated the dependence on water for fertilisation.

to HUMANS
  • Pollen are rich in nutrients and are used as food supplements.

  • Pollen consumption increases the performances of athletes and race horses.

  • Pollen can be preserved using liquid Nitrogen for future use (Cryopreservation)


DISADVANTAGES OF POLLEN

  • Pollen are small in size so can be inhaled during breathing.

  • Pollen of many species causes severe allergies and bronchial afflictions in some people.


29 views1 comment

Recent Posts

See All

1 Comment


Concise, lucid and informative. Keep it up and please keep posting such amazing content. I request for a dedicated series on genetics and biotechnology.

All the best team Biowiz!!!

Like

AD SPACE

bottom of page