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प्रश्न
Explain Lamarck’s Principle.
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उत्तर
- Lamarckism is the theory of inheritance of acquired characters from one generation to another, given by Jean-Baptiste Lamarck.
- It states that the morphological changes occurring in living organisms are responsible for evolution. This concept was based on the principle of use and disuse of organs.
- Morphological changes may occur gradually, either due to specific activities or the laziness of a particular organism.
- For e.g. Browsing on leaves of tall plants caused the neck of the giraffe to become long; frequent hammering movements cause the shoulders of ironsmith to become strong; inactivity caused weakening of the wings of birds like emu; legs of swans and ducks have become useful for swimming due to living in water; due to burrowing habits, snakes have lost their legs; etc.
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संबंधित प्रश्न
a) Explain in brief - Lamarck’s principle of ‘use or disuse of organs’.
b) Give two examples.
c) What are ‘acquired characters’?
Mention the two principles through which Lamarck explained his ideas.
Explain the occurrence of vestigial organs on the basis of Lamarck's theory of use and disuse.
Given alongside are two figures (A and B) showing a phenomenon that was first observed in Manchester before and after the year 1850.
Answer the following:
Give the common name and the scientific name of the insect involved in this phenomenon.
Given alongside are two figures (A and B) showing a phenomenon that was first observed in Manchester before and after the year 1850.
Answer the following:
The following phenomenon provides a classical explanation of a scientific theory given by a certain scientist.
(i) Name and explain the said theory.
(ii) Give the name of the scientist who gave this theory.
Theory of evolution : Darwin : : ____________ : Lamarck
What is inheritance of acquired characters?
The ‘use and disuse theory’ was proposed by ______.
The characters developed by the animals during their life time, in response to the environmental changes are called ______.
Observe the following figure and explain the concept.
The theory proposed by Lamarck is ______.
In which work and year was Lamarck's theory of evolution published?
Which environmental change did Lamarck cite as driving the evolution of the horse?
How were webbed feet in swimming birds explained under Lamarck's evidences?
According to the scientific conclusion that rejected Lamarckism, modifications caused by the environment or the 'use and disuse' of organs only affect which cells?
For an acquired trait to be transmitted to the next generation, which of the following cell types would need to be altered?
A newborn rat in Weismann's experiment was born with a normal tail even though its parents' tails had been cut off. This outcome directly contradicts which postulate of Lamarckism?
