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.
Define need of vitamin E and K during pregnancy period? Vitamin E needs are believed to increase during pregnancy but deficiency in humans rarely occurs. Vitamin E in the infan
Seed A seed is a mature ovule enclosing an embryonic plant, stored food material (in endosperm, persistent nucellus or embryo itself) and a seed coat formed by one or two inte
Define Factors Contribute to the Malabsorption - Radiation Damage? Malabsorption of water, fats, bile salts, carbohydrates, calcium, magnesium, iron and vitamin B 12 occur dur
What is the role of platelet plug formation in hemostasis? What events occur during platelet plug formation? Describe the circumstances that may induce inappropriate platelet plug
GOLGI APPARATUS Camillo Golgi in 1898 discovered a reticular structure in the cytoplasm of nerve cells with the help of metal impregnation technique using silver nitrate for whic
We are told that every surface we touch is teeming with bacterial cells, and bacteria are found in the pools we swim in, the water we wash with, and on the hands of friends. Why ar
Pre-conditions for GTT You are advised to carry out the GTT (OGTT) test to confirm a diagnosis of diabetes mellitus for a person with: a) The history of glycosuria (glucose
Q. How do arthropods grow? Due to the presence of exoskeleton the growth of an arthropod is periodical during the growth period the animal loses the exoskeleton, develops and g
Principles of Isolated soybean proteins The basic principles of ISP production are simple. Soybean protein isolates are obtained by selective solubilisation of the protein (e.
Coronary Arteries The right coronary artery originates form the right aortic valvular cusp, its, SA nodal branch supplies the SA node and AV nodal branch supply the AV nod
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