Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Q. Conditions Necessary for Outbreak of staphylococcal food? The following conditions are necessary for an outbreak of staphylococcal food poisoning: 1. The food must conta
Define the term Archenteron ? The name given to the primitive gut, the first tube that runs through the developing embryo and is open to the external environment. Formed during
1- Describe the function of enzymes in catalyzing biological reactions ? 2-Descride enzymes ' role in reducign activation energy?
What is the physiological cause of the syndrome known as cretinism? Cretinism is caused by chronic deficiency of the thyroid hormones (T3 and T4) during childhood. The chronic
Ooplasmic Determinants and Somatic Cell Determination Eggs of tunicates go through typically mosaic development in which the various blastomeres become determined to follow th
Do you know what the recommendations for fibre are? Well, the crude fibre intake should be 14 g/1000 Kcal. For adult woman 25 g/day and for adult man 38 g/day is desirable.
Disaccharides can be understood as follows 1.Sugars made up of the two monosaccharides held together by the covalent bond; like sucrose and lactose . 2. Type of sugar (sacch
Computed Tomograpy Scan Developments in cross-sectional imaging techniques such as spiral tomography and reformatted computerized tomograms have become increasingly popular in
Q. What is ecological succession? The Ecological succession is the changing sequence of communities that live in an ecosystem during a given time period.
name five animals in it''s trinomial nomenclature.
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd