How do organisms reproduce Worksheet-10

How do organisms reproduce Worksheet-10

 

Subjective questions:

  1. What is tissue culture?

 

  1. What changes does the male sex hormone, testosterone bring about?

 

  1. What is the name of the reproductive process which involves

(i) two parents  (ii) only one parent?

 

  1. Which type of reproduction

(i) involves gametes  (ii) does not involve gametes?

 

  1. Name one organism which reproduces :

(i) by binary fission   (ii) by spore formation

 

  1. Name one animal which regenerates from its cut body parts.

 

  1. Name the tissue through which the foetus gets all the requirements from the mother's body.

 

  1. How much is the reproductive life of a human female?

 

  1. Mention the site of implantation of embryo.

 

  1. What happens to the ovule and the ovary after fertilisation?

 

  1. What are the end products of 'double fertilisation'?

 

  1. Mention any two major functions of the human gonads.

 

  1. Define the term 'puberty'.

 

  1. Name two physical devices used for prevention of pregnancy.

 

  1. How does the embryo get nourishment inside the mother's body?

 

  1. If a woman is using a copper-T, will it help in protecting her from sexually transmitted diseases?

 

  1. What is the significance of fertilisation?

 

Answer:

  1. Tissue culture is the production or propagation of new plants from isolated plant cells or small pieces of plant tissue in a synthetic medium of culture solution.

 

  1. The male sex hormone testosterone brings about changes in appearance seen in boys at the time of puberty.

 

  1. (i) Sexual reproduction, (ii) Asexual reproduction.

 

  1. (i) Sexual reproduction. (ii) Asexual reproduction.

 

  1. (i) Amoeba, (ii) Rhizopus.

 

  1. Hydra.

 

  1. Placenta.

 

  1. Usually from 12 years to about 50 years i.e., from menarche to menopause.

 

  1. Uterus.

 

  1. After fertilisation, ovule changes to seed and ovary to fruit.

 

  1. The end products of 'double fertilisation' are the seeds and the fruits.

 

  1. The two main functions of human gonads are

(i) To produce the gametes and the sex hormones.

(ii) They help in the functioning of accessory sex organs and help in the development of sexual characters.

 

  1. Puberty is the age at which the sex hormones or gametes begin to be produced and the boy or girl becomes sexually mature.

 

  1. The two physical devices used for prevention of pregnancy are condom and diaphragm.

 

  1. The empbryo gets nourishment inside the mother’s body through placenta.

 

  1. If a woman is using a copper-T, it will not help in protecting her from sexually transmitted diseases.

 

  1. Enumerate the method of fertilisation as seen in a flowering plant.