Q.1

Ozone hole refers to

  • hole in ozone layer
  • decrease in the ozone layer in troposphere
  • decrease in thickness of ozone layer in stratosphere
  • increase in the thickness of ozone layer in troposphere
Q.2

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

  • angiosperms
  • gymnosperms
  • monocotyledons
  • dicotyledons
Q.3

Pollination is best defined as

  • transfer of pollen from anther to stigma
  • germination of pollen grains
  • growth of pollen tube in ovule
  • visiting flowers by insects
Q.4

Plants receive their nutrients mainly from

  • chlorophyll
  • atmosphere
  • light
  • soil
Q.5

Movement of cell against concentration gradient is called

  • osmosis
  • active transport
  • diffusion
  • passive transport
0 h : 0 m : 1 s