Answer to Question #111278 in Biology for Yogita sharma

Question #111278
List the characteristics of the pollen grains that are useful as taxonomic
evidences. Explain in detail.
1
Expert's answer
2020-04-22T08:07:07-0400

The characteristics of the pollen grains that are useful for the identification of the taxonomic features include:

  • size, shape, and symmetry. The pollen in modern flowering plants varies between 2.4 μm and 200 μm. The shapes of the pollan grains include circular, triangular, spheroidal, oblate, pro-late, etc. Grains may be symmetrical (radially, bilaterally symmetrical) or asymmetrical.
  • number and arrangement of pollen units. The pollen grains may be organized into tetrads, dyads, and polyads. The arrangement of pollen units can be categorized as tetrahedral, tetragonal, rhomboidal, linear, etc.
  • number, shape, and position of apertures. These are thin-walled in the outer pollen wall where the pollen tube emerges. The types of apertures include sulcus (elongated ectoaperture), ulcus (rounded aperture), colpus (long furrow-like aperture), etc. According to the position of the aperture, grains are classified as proximal, zonal, and global.
  • exine stratification. Exin is the outer layer covering the pollen. They can be distinguished by the presence and form of lectum, etc.

Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

Comments

No comments. Be the first!

Leave a comment

LATEST TUTORIALS
New on Blog
APPROVED BY CLIENTS