21.

Which one of the following contain agranal chloroplasts?

• C₃ plants

• Succulants

• C₄ plants

• Hydrophytes

Phycobilins absorb light of wavelength

• 670-700 nm

• 610-650 nm

• 500-650 nm

• 420-520 nm

For synthesis of one hexose sugar, how many times Calvin cycle is turned ?

• 12

• 2

• 6

• 3

The number of chlorophyll molecules in a quantasome is

• 50- 100

• 200- 250

• 300- 400

• 500- 600

A plant having seeds but lacking flowers and fruits belong to

• pteridophytes

• mosses

• ferns

• gymnosperms

Transpiration differ from evaporation in

• rate of water loss

• transpiration is a physiological process whereas evaporation is physical process

• transpiration is a physical process while evaporation is physiological process

• frequency of water loss

Pigments common to all algae are

• chlorophyll- a and phycobilins

• chlorophyll- a and carotenoids

• chlorophyll- a and chlorophyll- b

• chlorophyll- b and carotenoids

An antitranspirant is

• cobalt chloride

• mercury

• potassium

• phenyl mercuric acetate

Active K⁺ exchange mechanism for opening and closing of stomata was given by

• Darwin

• Levit

• Scarth

• Khorana

Quiescent centre is found in root apex and acts as

• permanent source of active initiates

• reservoir of resistant cells

• reservoir of passive cells to form new root apex if root apex is damaged/ killed

• all of the above