Question

Question - 2 How did Lamarck experiment on Giraffes?
And How Weisman rejected Lamarck's Theory?

Answer 1

Lmarck said that during the life time of an organism new characters develop due to internal vital forces, effect of environment, new needs and use and disuse of organs. According to him these acquired characters are inherited from one generation to another. By continuous inheritance through many generation these acquired characters tend to make new generation quite different from its ancestors resulting in the formation of new species.

In support of his hypothesis he presented the case of giraffe. He said that present day giraffe has evolved from a deer like ancestor with small neck and small forelimbs. This ancestor happens to live in barren place, where leaves of trees were the only food available to it. In making effort to reach the leaves, it continuously stretched its neck and forelimbs. This resulted in slight elongation of these parts. The increase acquired in one generation was transmitted to the next generation, in which further elongation occured due to similar efforts. This process after a number of generations, produced the present-day giraffe with long neck and long forelimbs.

Answer 2

Now my frnd Weisman on my suggestion conducted an experiment on rats (poor rats). He cut off there tails for about 22 generations but there was no reduction in the size of tail. On the basis of this experiment (which was suggested by me) he proposed the theory of continuity of germplasm and rejected (actually kicked his #$%% ) Lamarck's theory.

Answer 3

Got it v?

Answer 4

And Germplasm Theory says human body has two types of cells:
(a) Somatic meaning body cells
(b) Germplasm meaning sex cells??

Answer 5

Yeah I am getting it buddy. :)

Answer 6

yes and any change in germplasm is inherited while changes in somatic cells are not inherited. So suppose if i hit the gym hard and get a 6 pack ab (which i already have), it doesn't mean that my son or daughter will inherit that too because those changes are somatic changes.

Answer 7

Yeah Germplasm or sex cells will take it to chromosomes, so it is inherited.

Answer 8

Thanks abhisar. :)

Answer 9

ur welcome :)