(a) What is the law of dominance of traits? Explain with an example.
(b) Why are the traits acquired during the life time of an individual not inherited? Explain.
Answer:
(a)
The law of dominance of traits states that “When parents having pure contrasting characters are crossed then only one character expresses itself in F1 generation . This character is the dominant character and the character which cannot express itself is called a recessive character ”.
Example:
When purebred tall (TT) pea plants are crossed with purebred dwarf (tt) pea plants, all the plants in the F 1 progeny are tall(Tt) .
The appearance of all Tall plants in the F 1 generation shows that tallness is the dominant character while dwarfness is the recessive character.
(b)
Traits acquired during the lifetime of an individual do not reflect in the reproductive tissues .
Changes in the non-reproductive tissues are not passed on to the DNA of the germ cells and therefore not inherited by the next generation.