How is the sex of a newborn determined in humans?

Give the pair of contrasting traits of the following characters in pea plant and mention which is dominant and recessive (i) yellow seed

Mention three important features of fossils which help in the study of evolution.

Does the occurrence of diversity of animals on earth suggest their diverse ancestry also? Discuss this point in the light of evolution.

Why do all the gametes formed in human females have an X chromosome?

In human beings, the statistical probability of getting either a male or female child is 50 : 50. Give a suitable explanation.

Give the pair of contrasting traits of the following characters in pea plant and mention which is dominant and recessive (ii) round seed

What are homologous structures? Give an example. Is it necessary that homologous structures always have a common ancestor?

Do genetic combination of mothers play a significant role in determining the sex of a new born?

A woman has only daughters. Analyse the situation genetically and provide a suitable explanation.

Why did Mendel choose pea plant for his experiments?

A very small population of a species faces a greater threat of extinction than a larger population. Provide a suitable genetic explanation.