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!
SEXUAL REPRODUCTIONYou must be aware that reproduction is one of the distinguishing features of living beings. Reproduction is basically of two types: asexual and sexual. In asexual reproduction an organism propagates itself without the formation of sex cells or gametes. Sexual reproduction is more complex than the asexual type. It is based on the production of two kinds of gametes, the male and the female. The gametes are microscopic and in order that they fuse, certain specific conditions are required. This makes sexual reproduction so very specialised.
You may question why a complex and difficult mode of reproduction is found in nature when a simpler mode is available. It is because, an offspring that has been produced asexually has exactly the same genetic constitution Like that of its parents. Asexual reproduction necessarily involves mitosis which is a conservative process maintaining the status quo ante of the genetic material. On the other hand, sexual reproduction causes genetic variability in offspring. This is due to meiosis which is an essential component of sexual reproduction. Meiosis generates enormous variation through dependent assortment ofh omologous chromosomes and crossing-over. In addition, randam fusion of gametes at the time of fertilisation also contributes in generating variation.
You may recall that genetic.variability is a precondition for biological evolution. A species that is unable to evolve would sooner or later become extinct. Sexual reproduction hence is seen in a majority of existing forms of life to bring aboutvariability. To ensure a sexual mode of reproduction, most organisms have evolved different 'mating types' or 'sexes'.
In nature there is a vast array of diverse mechanisms of sex determination in different species.
Nuclear transport is an energy-dependent process mediated through saturable receptors. Export and Import receptors are by to distinguish and bind to nuclear localization signals or
Types of survivorship curves
What is a cytoskeleton? What are its main constituents in animal cells? Cytoskeleton is the cytoplasmic structure that handles the cell, keeps its shape and fixates and moves t
Describe the Advantages and Disadvantages of insulin pump Advantages - Insulin pumps deliver more precise amounts of insulin. This supports control over blood sugar level,
What is the excreatory organ of crab
Q. Common Disorders of Coronary Heart Diseases? We shall deal with different types of heart diseases, their- etiology, symptoms, complications, as well as, nutrition and dietar
Explain Temperate Deciduous Forests-Taiga and tundra? Temperate deciduous forests are typified by the type of forests predominantly found in the eastern and northeastern Unit
True or false, adaptations are the result of finding the best or only solution to a given problem a species faces.
Oxygen - Aquatic Ecosystem Oxygen is found in waters in dissolved form. It enters the aquatic ecosystem through the air water interface and by the photosynthetic activities of
Structural classification of bone Macroscopically, bone tissue can be classified into two types, compact and trabecular bone. Compact bone is dense, corticated and makes up the
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