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!
Chromosomes and Their Organization
During division phase , the duplicated chromatin fibres become extremely shortened (= condensed), by coiling and folding ,into short think and microscopically visible rod like structures of various shapes and sizes, It is necessary to learn about these structures before dealing with the sequential changes of mitosis. These structures werer observed first by Naegeli 1842 and later by russow 1872 and Balbiani 1876 waldeyer 1888 named these, chromosomes gr.khroma =coloured + soma =body ) because these take a dark stain when treated with basis dyes.
Karyotype :Beneden 1888 discovered that the chromosomal pattern is a specific character .i.e. each species has its own chromosomal complement different from those of all other species ,This complement of a species is called its karyotype .It implies that in all cells membrane of a plant or animals species, not only the number of chromosomal is the same but even the shapes sizes, and structure of the various chromosomes in the set are the same .The chromosomal number varies from 10 to 50 in most of the species, The smallest number is however two found in a nematode subspecies ascaris megalocephala univalence, and the largest number is 1600 in aulacantha ( a radiolarian protozoan ) To quote a few examples the chromosomal number is 46 in man ( Homo sapiens ) 32 in Hydra vulgaris. 12 in housefly (Musca domestica ) 26 in frog (Rana pipiens ) in rabbit, (Oryctolagus cuniculus ) 38 in cat (Felish domesticus ) 78 in dog (cains familiaris) 80 in pigeon (Columba livia) 8 in fruitfly ( Drosophila melanogaster ) in mosquito ( Culex pipiens ) and so on.
S t r a tegic and tactic control of parasitic diseases The reduced performance of the animals in terms of decreased milk yield, draught power, breeding performance, poor bo
Q. Which respiratory adaptations or organs do aquatic and terrestrial arthropods respectively present? In crustaceans, typical aquatic beings, there are richly vascularized gil
Q. Why, even though they have an open circulatory system, can flying insects like flies beat their wings with great speed? In insects the circulatory system is open but this sy
Define the effect of Deficiency of Vitamin C? Severe ascorbic acid deficiency results in the development of the disease known as scurvy, three important manifestations of scur
Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
cymose
List three human activities which could cause the loss of a species. Human activities which threaten species with extinction are: (i) hunting of individual species, (ii) over-
Give an example of how two organisms are interdependent.
Evaluation of feedstuff In the feed manufacturing process evaluation of the feed ingredients is very important in achieving consistent quality throughout the year. If one is a
What is the function of vitamin E? In which foods can it be found? Vitamin E, or tocopherol, is a fat-soluble vitamin that participates as coenzyme in the respiratory chain, t
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