Science Class 7th

161. In sexual reproduction offspring may have _______from the parent’s physical features.

A) Variations

B) Identical

C) None of these

162. The transfer of pollen grains to the stigma of the carpel is called ________.

A) Pollination

B) Layering

C) Grafting

163. ___________ is the transfer of pollen grains from the stamen to the stigma of the same flower or to the different flower of the same plant.

A) Self-pollination

B) Cross-pollination

C) None of these

164. _______ is the transfer of pollen grains from the another to the stigma of a flower on another plant of same species.

A) Self-pollination

B) Cross-pollination

C) None of these

165. A benefit of __________ is the development of plants which are stronger and grow more vigorously in their environment.

A) Self-pollination

B) Cross-pollination

C) None of these

166. During the ________ process, pollen grains stick to insects and the insects carry the pollen grain to next flower.

A) Pollination by insect

B) Pollination by birds

C) Pollination by winds

167. ___________ flowers are usually brightly coloured with large amount of nectar and are tube-shaped.

A) Birds pollination

B) Wind pollination

C) Water pollination

168. ____________flowers are produced by the plants living in water.

A) Birds pollination

B) Wind pollination

C) Water pollination

169. __________is the fusion of male and female sex cells, to form zygote.

A) Fertilization

B) Pollination

C) Reproduction

170. The mass of cells finally develops into a tiny plant known as ______.

A) Embryo

B) Zygote

C) Both a & b

171. The embryo is in the center of ovule and is surrounded by a tissue called _____________.

A) Zygote

B) Reproduction

C) Endosperm

172. Endosperm stores the food for the _______.

A) Embryo

B) Zygote

C) Both a & b

173. The embryo and the endosperm are surrounded by a tough protective layer known as _________.

A) Testa

B) Zygote

C) Both a & b

174. Testa, endosperm and embryo are collectively called the ___________

A) Seed

B) Leave

C) Root

175. Which one of the following is the female sex organ?

A) Stamen

B) Carpel

C) Petal

D) Sepal

176. Potato is asexually produced through:

A) Layering

B) Tubers

C) Cutting

D) Grafting

177. Self-pollination occurs between.

A) Same flower

B) Different flower

C) Flower of different plants

D) Same or different flowers of the same plant

178. Seed develops from:

A) Ovule

B) Ovary

C) Anther

D) Both ovary and ovule

179. Which one of the following is not a reproductive structure:

A) Sepal

B) Carpel

C) Ovule

D) Pollen grain

180. An ___________ is community of plants, animals and smaller organism that live, feed, reproduce and interact with one another and with their environment.

A) Ecosystem

B) Global warming

C) Both a & b