NCERT Class X Science Class: Chapter –8. How Do Organisms Reproduce? – Part-9

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Question 50:

Write two points of difference between asexual and sexual types of reproduction. Describe why variations are observed in the offspring formed by sexual reproduction.

Answer:

Question 50 Mitosis and Meiosis
Question 50 mitosis and meiosis

Asexual Reproduction

Sexual Reproduction

A.

Involves only one parent

I.

Often involves two

parents

B.

Gametes are not

produced

II.

Gametes are produced

C.

No fertilization and

zygote formation

III.

Fertilization and zygote

Formation is observed.

D.

Meiosis does not occur

at any time during

reproduction

IV.

Meiosis occurs at the

time of gamete

formation

During sexual reproduction, two types of gametes fuse. Although the gametes contain the same number of chromosomes, their DNA is not identical. This situation generates variations among the off springs.

Question 51:

Distinguish between pollination and fertilization. Mention the site and product of fertilization in a flower.

Draw a neat, labelled diagram of a pistil showing pollen tube growth and its entry into the ovule.

Answer:

The process or mechanism of transfer of pollen grains from the anther to the stigma is termed pollination.

The fusion of male and female gametes giving rise to zygote is termed fertilization.

  • The site of fertilization is ovule.

  • The product of fertilization is zygote

Image labelled diagram of a pistil showing pollen

Image Labelled Diagram of a Pistil Showing Pollen

Image labelled diagram of a pistil showing pollen