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.
The dominant bonds holding together non-polar compounds that are immersed in aqueous solution are _________, and the forces that hold pure solutions of non-polar compounds are ____
What part do (a) nitrifying, (b) nitrogen-fixing and (c) denitrifying bacteria play in the nitrogen cycle? a) Nitrifying bacteria in the soil change ammonia and other nitrogeno
What is allele frequency? The Allele frequency is the percentage of appearances of an allele in the genotypes of a given population (compared to the other alleles of the studie
Explain about the Simple Proteins? Simple proteins are those that are made of amino acid units just joined by peptide bond. Upon hydrolysis they yield a mixture of amino acids
Explain Procedure for Analysis of Air of Processing Facility? Now conduct the experiment following the steps enumerated herewith: 1. Label the Petri plates with nutrient aga
STRUCTUR E OF PROTEINS Proteins which are mixed polymers of amino acids can have up to four structural levels - Primary, Secondary, Tertiary, Quaternary 1 . PRIMA
FUNCTIONS BASED ON MANAGEMENT PRINCIPLES: Planning: The objectives of nursing unit should be achieved through planning, good coordination and supervision. While planning nur
EYELID S - 3 in number. Dermis is thinnest in it. Upper and lower eye lid with eye lashes. Upper eye lid is more motile In reptiles lower eye lid is more motile. In cycl
what are the ecological importance of molluscus
SALI V A R Y GLAND - These are compound - Alveolar, tubular glands made up of columnar / cuboidal epithelium. Saliva is manufactured in them. In mammals these are pai
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