Advertisements
Advertisements
Question
Why are the traits acquired during the life time of an individual not inherited? Explain.
Advertisements
Solution
Acquired traits (like muscle built by exercise or a scar) arise from environmental effects on an individual’s somatic cells and do not change the DNA of gametes. Because inheritance depends on alterations in the germ line, somatic modifications are not passed to offspring, this is the Weismann barrier separating soma and germ line. Lamarck’s idea that acquired characters are inherited was thus disproved; only genetic changes (mutations) or stable germ-line epigenetic marks can be inherited, and these are rare. Therefore, traits acquired during life are generally not transmitted to the next generation.
RELATED QUESTIONS
How do Mendel's experiment show that traits are inherited independently?
In a monohybrid cross between tall pea plants (TT) and short pea plants (tt), a scientist obtained only tall pea plants (Tt) in the F1 generation. However, on selfing the F1 generation pea plants, he obtained both tall and short plants in F2 generation. On the basis of above observations with other angiosperms also, can the scientist arrive at a law? If yes, explain the law. If not, give justification for your answer.
Mendel crossed tall pea plants with dwarf pea plants in his experiment. Write his observations giving reason on the F1 and F2 generations.
A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as:
Outline a project which aims to find the dominant coat colour in dogs.
Give the contrasting traits of the following characters in pea plant and mention which is dominant and which is recessive :
Round seed
For his experiments on heredity, Mendel used :
papaya plants
potato plants
pea plants
pear plants
Explain the mechanism of hereditary changes.
What is genetics?
In the following figure showing a germinating gram seed, name the parts labelled as A, B and C:
Why is Part 'B' considered to be important during germination?
