Biology - Study Mode

[#946] Ozone hole refers to
Correct Answer

(C) decrease in thickness of ozone layer in stratosphere

Explanation

Solution: The term 'ozone hole' refers to the depletion of the protective ozone layer in the upper atmosphere (stratosphere) over Earth's polar regions. Stratospheric ozone is constantly produced by the action of the sun's ultraviolet radiation on oxygen molecules (known as photochemical reactions).

[#947] Pine, fir, spruce, cedar, larch and cypress are the famous timber-yielding plants of which several also occur widely in the hilly regions of India. All these belong to
Correct Answer

(B) gymnosperms

Explanation

Solution: Pine, fir, spruce, cedar, larch and cypress are the famous timber-yielding plants of which several also occur widely in the hilly regions of India. All these belong to gymnosperms, a taxonomic class that includes plants whose seeds are not enclosed in an ovule.

[#948] Plants receive their nutrients mainly from
Correct Answer

(D) soil

Explanation

Solution: Plants receive their nutrients mainly from soil.

[#949] Photosynthesis generally takes place in which parts of the plant?
Correct Answer

(A) Leaf and other chloroplast bearing parts

Explanation

Solution: In plants, the process of photosynthesis takes place in the mesophyll of the leaves, inside the chloroplasts. Chloroplasts contain disc-shaped structures called thylakoids, which contain the pigment chlorophyll.

[#950] Most fish do not sink in water because of the presence of: I. swim bladder II. air bladder III. air sacs IV. air in spongy bones
Correct Answer

(A) I and II are correct

Explanation

Solution: Fishes have a swim bladder or air bladder which helps them to remain buoyant without sinking in water. They are present in the body cavity.