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

Proteins of plant origin - seed proteins, Proteins of Plant Origin - Seed P...

Proteins of Plant Origin - Seed Proteins Seed Proteins: Although a large number of plants produce seeds having protein contents in excess of 15%, only a few are utilized for fo

Describe three ways that rna differs from dna, Describe three ways that RNA...

Describe three ways that RNA differs from DNA. RNA is single stranded; DNA is double stranded all of the codons from the deletion point to the end of the transcript would be s

Significance of fertilization, SIGNIFICANCE OF FERTILIZATION - 1.      ...

SIGNIFICANCE OF FERTILIZATION - 1.      In fertilization process number of chromosome are diploid in zygote. 2.      During fertilization male & female chromosomes are combi

Sex-limited traits, Sex-Limited Traits Sex Limited Traits are traits ex...

Sex-Limited Traits Sex Limited Traits are traits expressed only in one sex, although the genes controlling thcm arc prcscnt as wcll as transmitted to both thc sexes. Therefore,

Sequence for the beta actin gene, The sequence for the Beta Actin gene (ACT...

The sequence for the Beta Actin gene (ACTB) is given below. Which pair of primers (designed to amplify the entire sequence below) could be used to successfully produce the beta act

Breathing and exchanges of gases , What happens to respiratory system in a ...

What happens to respiratory system in a man going up a hill?

Explain the secretary phase - menstrual cycle, Explain the Secretary Phase ...

Explain the Secretary Phase - Menstrual Cycle After ovulation, the lining of ovarian follicle is stimulated by LH to develop corpus luteum which produces progesterone. The endo

Breeder select for in a cereal crop, What characteristics might a breeder s...

What characteristics might a breeder select for in (i) a cereal crop, (ii) a farm animal? (i) In a cereal variety, a breeder might select for high yield; disease-, frost- or dr

Dietetic foods for diabetes, Dietetic Foods for diabetes: With advances...

Dietetic Foods for diabetes: With advances in food technology, foods for special use by diabetics are now available in the global market, they are emerging in India also. These

Explain beef extract and yeast extract, Explain Beef Extract and Yeast Extr...

Explain Beef Extract and Yeast Extract These are aqueous extracts of lean beef and brewer's yeast, respectively. Beef extract provides amino acids, peptides, nucleotides, organ

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