NCERT Class X Science Solutions: Chapter 8 – How Do Organisms Reproduce? Part 1

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Question 1:

Asexual reproduction takes place through budding in

  1. Amoeba.

  2. Yeast.

  3. Plasmodium.

  4. Leis mania.

Answer:

Asexual reproduction takes place through budding in yeast.

Asexual reproduction takes place through budding in Yeast

Asexual Reproduction Takes Place through Budding in Yeast

Budding is a form of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at one particular site. The new organism remains attached as it grows, separating from the parent organism only when it is mature,, leaving behind scar tissue.

Question 2:

Which of the following is not a part of the female reproductive system in human beings?

  1. Ovary

  2. Uterus

  3. Vas deferens

  4. Fallopian tube

Answer:

C. Vas deferens is not a part of the female reproductive system in human beings.

Question 3:

The anther contains

  1. Sepals.

  2. Ovules.

  3. Carpel.

  4. Pollen grains.

Answer:

The anther contains pollen grains that release pollen on the outside of the anthers that brush against the insects that enter the flower.

The pollen is then transported by the insect to the stigma of another flower or the same flower. This fertilizes the ovule.

This image shows structure of stamen

Structure of Stamen

Question 4:

What are the advantages of sexual reproduction over asexual reproduction?

Answer:

Advantages of sexual reproduction:

  • In sexual reproduction, more variations are produced. Thus, it ensures survival of species in a population.

  • The new formed individual has characteristics of both the parents.

  • Variations are more viable in sexual mode than in asexual one. This is because in asexual reproduction, DNA has to function inside the inherited cellular apparatus.

Result for sexual reproduction

Sexual Reproduction

Question 5:

What are the functions performed by the testis in human beings?

Answer:

The testes are the male reproductive organs that are located outside the abdominal cavity within a pouch called scrotum.

Functions of testes:

  • Produce sperms

  • Produce a hormone called testosterone, which brings about secondary sexual characters in boys.

Question 6:

Why does menstruation occur?

Answer:

Menstruation is a process in which blood and mucous flows out every month through the vagina. This process occurs every month because one egg is released from the ovary every month and at the same time, the uterus (womb) prepares itself to receive the fertilized egg. Thus, the inner lining of the uterus gets thickened and is supplied with blood to nourish the embryo. If the egg does not get fertilized, then the lining of the uterus breaks down slowly and gets released in the form of blood and mucous from the vagina.

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