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!
Preformation Theory (1632-1723)
(i) Scientist 'Malpighi Swammerdam' propounded the preformation theory. This theory holds that the sex cells (sperm and ova) had the miniature copy of adults and the development of embryo was actually only the enlargement of parts that were already present in the sperm or egg.
(ii) This miniature form of the animal present in the gamete was called 'Homunculus'.
(iii) This theory was supported by Hartsoeker.
(iv) Those who considered homunculus to be present is sperms were called Spermist.
(v) Leeuwenhoek & Hartsoeker believed that miniature of organism was present in the head of the sperm.
(vi) Those who considered homunculus to be present in ova (eggs) were called Ovist.
(vii) The term preformation covers the both.
(viii) Malpighi, Swammerdam & Bonnet believed that miniature organism was present in the egg.
Ask question #Minimum 100 hhejejhjehjwords accepted#
Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
Define Causes of Vitamin A Deficiency - Inadequate diet? A child is born with poor stores of vitamins and minerals due to maternal malnutrition. Diets of pregnant women are def
Organogenesis - Plant Tissue and Organ Culture Organogenesis refers to the differentiation of organs such as roots, shoots or flowers. Shoot bud differentiation may occur dire
Biochemical Production: Plants are the foundation of a large variety of biochemical which are metabolites of both secondary and primary metabolism. But secondary metabolites ar
Alkaline Phosphatase is an enzyme which catalyzes the hydrolysis of the phosphomonoesters of the 5' nucleotides. It is used to dephosphorylate (remove phosphate groups from) the 5
Q. Explain Left Atrial Enlargement ? This chamber is oval in the frontal projection and flattened in lateral projection. On the PA view, its appendage makes a small contributio
Alterations occurring in nuts and oilseeds Some oilseeds have acquired a great significance in the large-scale industrial production of edible oils. You have already studied t
What is Mendel's second law? Mendel's second law postulates that two or more different traits are also conditioned by two or more pair of dissimilar factors and that each inhe
Q. Define Left Posterior Hemiblock? Bobbna and associated reported four cases in which they proposed that the left posterior hemi block was initiated by exercise. In their pa
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd