Important Question for class 12 Biology Academic team of entrancei prepared selected questions for class 12 Biology download your free copy of class 12 biology questions from entrancei . do find NCERT solutions for class 12 Biology Prob 1.
How does plant morphology help in classification?
Sol.
Morphology provides distinguishing features of stem type, leaf type, inflorescence, flower structure, fruit type etc in classification.
Prob 2.
What is the function of vegetative organs of a plant?
Sol.
Vegetative organs take part in nutrition, growth and maintenance of plant body.
Prob 3.
What is the type of origin of root branches?
Sol.
Endogenous
Prob 4.
Pneumatophores are covered by cork. How do these roots help in gaseous exchange?
Sol.
They bear small pores called lenticles (=pneumathodes) near their tips.
Prob 5.
How can a plant stem protect against grazing?
Sol.
The stem provides protection against grazing animals when modified into thorns (e.g. Duranta) or bears prickles (e.g. Rose).
Prob 6.
How is a phyllode helpful to a plant?
Sol.
Formation of phyllode is a mechanism to reduce transpiration.
Prob 7.
Amongst pea tendrils, Opuntia spines, lemon thorns and cucurbit tendrils, which ones are homologous structures? Give reason.
Sol.
Pea-tendrils and Opuntia spines are the homologous organs because they have same origin (nodes) and are modifications of leaves but perform different functions. Lemon thorns and cucurbit tendrils are both stem modifications, and are homologous organs.
Prob 8.
Amongst opuntia spines, lemon thorns, rose prickles and gourd tendrils, which ones are homologous organs and why?
Sol.
Lemon thorns and gourd tendrils are homologous organs as they have the same origin, are structurally stem branches but perform different functions.
Prob 9.
Name any one plant in which adventitious roots develop chlorophyll and perform photosynthesis.
Sol.
Tinospora
Prob 10. Which part of the plant leaf is modified to form the spines of Acacia and the sheath covering the leaf of Ficus elastica? Sol.
Stipules.
Entrancei