Sterility in angiosperms, Biology

Assignment Help:

Sterility in Angiosperms

Sterility in angiosperms may arise due to several causes. Either the anther may not be formed, or anthers are formed but meiosis may be abnormal.

A. In situations where anthers are not formed, they may take abortive forms and appear like petals or sepals. These conditions are referred to as petaloid and phyllody respectively. There are even cases where anther formation may be suppressed altogether. These cases of pollen sterility have premeiotic determination.

B. There are other examples in which anthers are produced but meiosis is abnormal resulting in the formation of non-viable pollen.

C. Sometimes normal pollen grains are formed but they are not released. This results from failure of anther dehiscence. Such a situation is also described by the term contabiscent anther.

D. Sometimes meiosis is normal but abortion can take place due to premature dissolution of callose. This can occur at any stage during microsporogenesis.


Related Discussions:- Sterility in angiosperms

Protein percentage in lowry method, How to calculate protein percentage in ...

How to calculate protein percentage in Lowry method? Ans) By verification of optical density by coloimetric method

Anti-diuretic hormone, who discovered it? and what is it''s physiologic fun...

who discovered it? and what is it''s physiologic functions?

What does s-shaped pattern of population growth show, What does S-shaped pa...

What does S-shaped pattern of population growth show? How is J-shaped pattern dissimilar from it and why?

Stomatal resistance, Stomatal Resistance Stomatal resistance is most i...

Stomatal Resistance Stomatal resistance is most important because gas exchange between leaves and external atmosphere takes place entirely through stomatal pores. Stomatal res

Explain about the stilbenes, Explain about the Stilbenes? Stilbenes con...

Explain about the Stilbenes? Stilbenes contain 3 phenyl compounds connected by a 2-carbon methylene bridge and occur in nature in restricted distribution. In plants, they act a

Cardiomyocytes and motor neurons, Describe the mechanisms and genetic regul...

Describe the mechanisms and genetic regulations that underpin how two cells such as cardiomyocyte and a motor neuron have identical gnomes, yet are functionally and structurally di

Main prophylactic measures against schistosomiasis, What are the main proph...

What are the main prophylactic measures against schistosomiasis? The main measures to stop schistosomiasis are: information for infected individuals to look for treatment and t

Functions of protein, FUNCTION S OF PROTEIN Proteins from the collo...

FUNCTION S OF PROTEIN Proteins from the colloidal complex of the protoplasm and its organelles. Most Abundant Protein in Organic World is RUBISCO or Ribulose biphosp

How many grams of sodium dodecyl sulfate need, How many grams of sodium dod...

How many grams of sodium dodecyl sulfate (mw = 288.37) would you dissolve in 80mLs of water to make a 20% solution of SDS?

Rna secondary structure, Most  RNA  molecules  are  single-stranded  but  a...

Most  RNA  molecules  are  single-stranded  but  an  RNA  molecule  should  hold regions  that  can  form  complementary   base  pairing  where  the  RNA  strand loops  back  on  i

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd