Human Health and Disease — BIOLOGY STD 12 Science — Question

Name the type of evolution that has resulted in the development of structures like wings of butterfly and bird. What are such structures called?

In case of an infertile couple, the male partner can inseminate normally but the mobility of sperms is below 40 per cent. Judge, which kind of ART is suited in this situation to form an embryo in the laboratory, without involving a donor?

How many types of tumors are there? Write name.

Identify True/ False statements. Correct each false statement to make it true.
Leydig cells synthesise androgens. (True/ False)

Write the names of products obtained by using microbes in industries.

Name the main source of air pollution.

When a tall pea plant was self–pollinated, one–fourth of the progeny were dwarf. Give the genotype of the parent and dwarf progenies.

How does smoking tobacco in human lead to oxygen deficiency in their body?

Which of Mendel's Law of Inheritance is universally acceptable and without exception? State the law.

On what basis is skin colour in humans considered polygenic?