Punjab Board Class 12 Biology — Flashcards for Quick Revision

A: A flower is a specialized reproductive organ of angiosperms that contains the sites of sexual reproduction. The two most important reproductive structures are: (1) Androecium - consisting of stamens (

A: A stamen is the male reproductive organ of a flower consisting of two main parts: (1) Filament - a long, slender stalk that attaches to the thalamus or petal, and (2) Anther - the terminal, typically

A: A microsporangium is a pollen sac within the anther that contains developing pollen grains. It is surrounded by four distinct wall layers from outer to inner: (1) Epidermis - provides protection, (2)

A: The male reproductive system consists of: (1) A pair of testes - the primary organs that produce sperms and androgens; (2) Male sex accessory ducts - rete testis, vasa efferentia, epididymis, and vas

A: The testes are housed in the scrotum, a pouch-like structure located outside the abdominal cavity, because they require a lower temperature than the normal body temperature for spermatogenesis (sperm

A: Seminiferous tubules are highly coiled tubules found inside the testis, with 250 testicular lobules each containing 1-3 tubules. The inner lining of seminiferous tubules contains two types of cells: (

A: Reproductive health refers to a total well-being in all aspects of reproduction—physical, emotional, behavioural, and social. It means having physically and functionally normal reproductive organs wit

A: The RCH programme is India's comprehensive national initiative launched to achieve total reproductive health as a social goal. Its main objectives include: (1) Creating awareness about reproduction-re

A: India's population grew explosively due to improved health facilities and better living conditions. The population increased from 350 million at independence to over 1.2 billion by 2011. The populatio