IB Past Paper Question Analysis Topic: Biology - Heredity and Evolution
(1) How does the creation of variations in a species promote survival?
Solution:
The changes in the environment are happening every day.
With time the genetic variation in an organism helps them to adapt more due to natural selection.
These variations in a population enable the stability of various species.
It does that by preventing them from getting wiped out during adverse conditions.
Hence, the creation of variation helps in promoting survival.
(2) In evolutionary terms, we have more in common with
A. A Chinese school-boy
B. A chimpanzee
C. A spider
D. A bacterium
Solution
In terms of evolution, organisms belonging to the same species have more in common than organisms belonging to different species of the same genus or different genus. We have more in common with a Chinese school-boy because both belong to the same species of Homo sapiens, and thus, share a common ancestor.
(3) Why are traits acquired during the lifetime of an individual not inherited?
Solution:
This happens because an acquired trait involves change in non-reproductive tissues (somatic cells) which cannot be passed on to germ cells or the progeny. Therefore, these traits cannot be inherited.