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

Explain nutritional and functional role of calcium, Minerals :- Calcium    ...

Minerals :- Calcium      Food Source      Dairy products, leafy vegetables, tofu, fish bones green Nutritional/Functional role Essential nutrient: Deficiency lead

Which of the vertebrate classes are warm-blooded, Which of the vertebrate c...

Which of the vertebrate classes (a) are 'warm-blooded', (b) reproduce by laying eggs?   (a) Birds and mammals are 'warm-blooded'. (b) Fish, Amphibia, Reptiles

Autoradiography, Autoradiography is the process to detect radioactively la...

Autoradiography is the process to detect radioactively labeled molecules (which commonly have been separated in an SDS-PAGE or agarose gel) based on their ability to develop an im

Illustrate about the neuropsychological assessment, Illustrate about the ne...

Illustrate about the neuropsychological assessment A neuropsychological assessment is a clinical examination of both the working brain and dysfunctional brain. Neuropsychologic

The final concentration of the solution, Assume that you have 1 ml of a sol...

Assume that you have 1 ml of a solution of amylase (an enzyme) at a concentration of 15 mg protein/ml. Calculate the volume of diluting buffer that you would have to add to 1.0 ml

What is the formula of the net primary production, Q. What is the formula o...

Q. What is the formula of the net primary production (NPP)? How does NPP relate to the energy pyramids? The Net primary production is the gross primary productivity less the or

Define disadvantages of using bacteria as source of protein, Define Disadva...

Define Disadvantages of using Bacteria as a source of protein? Disadvantages of using Bacteria as a source of protein are as follow: a) If the bacterial strain is very small

Describe the theory of darwins, Describe the theory of Darwin's? Most s...

Describe the theory of Darwin's? Most scientists today accept the theory that living organisms have evolved according to the concept that was first proposed by Charles Darwin i

Peroxisome and lysosome, e use itwhat is difference between peroxisme and l...

e use itwhat is difference between peroxisme and lysosome what is function of it and where w

1.notochord, general character and classification of platyhelminthes

general character and classification of platyhelminthes

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