Lakhmir Singh & Manjit Kaur: How do Organisms Reproduce?, Solutions- 1 | Science Class 10 PDF Download

Page No - 141

Question 1:
Which life process ensures that a plant or animal species will not disappear from this earth ?
Solution :
Reproduction. 

Question 2:
What is the name of the reproductive process :
(a) which involves two parents ?
(b) which involves only one parent ?
Solution :
(a) Sexual reproduction.
(b) Asexual reproduction.

Question 3:
State whether the following statement is true or false :
Spores produced by the bread mould plant are actually its seeds.
Solution :
False.

Question 4:
Most of the plants reproduce by sexual method. Name two plants which can reproduce asexually.
Solution :
Ferns and mosses.

Question 5:
Which type of reproduction :
(a) involves gametes ? .
(b) does not involve gametes ?
Solution :
(a) Sexual reproduction.
(b) Asexual reproduction.

Question 6:
State whether human beings reproduce by sexual method or asexual method.
Solution :
Sexual method.

Question 7:
(a) Name two animals which reproduce sexually.
(b) Name two animals which reproduce asexually.
Solution :
(a) Dogs and cows.
(b) Amoeba and Hydra.

Question 8:
Name one organism which reproduces by spore formation.’
Solution :
Bread mould (Rhizopus fungus).

Question 9:
Name the method by which Paramecium reproduces. Is this method sexual or asexual ?
Solution :
Binary fission; Asexual method.

Question 10:
Name two plants :
(a) which can be grown from their broken stems.
(b) which can be grown from their leaves.
Solution :
(a) Bryophyllum and money plant.
(b) Bryophyllum and Begonia

Question 11:
Name the asexual method of reproduction in yeast.
Solution :
Budding.

Question 12:
Name the asexual method of reproduction in (a) Hydra, and (b) Plasmodium.
Solution :
(a) Budding and regeneration. (b) Multiple fission.

Question 13:
What is the name of asexual reproduction method in :
(i) Spirogyra, and (ii) Leishmania ?
Solution :
(i) Fragmentation.
(ii) Binary fission.

Question 14:
Name the artificial propagation mehod used for the propagation of (a) rose plants, and (b) apple trees.
Solution :
(a) Cutting.
(b) Grafting.

Question 15:
Which artificial propagation method is used for the production of jasmine plants ?
Solution :
Layering.

Question 16:
Name the natural method by which strawberry plants are propagated.
Solution :
Layering.

Question 17:
Name two plants which are propagated by layering method.
Solution :
Hibiscus and Bougainvillea.

Question 18:
Name any two plants which are propagated by cuttings method.
Solution :
Rose and grapes.

Question 19:
Write down the different methods of asexual reproduction.
Solution :
The different methods of asexual reproduction are:(i) Fission(ii) Budding.(iii) Spore formation.(iv) Regeneration.(v) Fragmentation.(vi) Vegetative propagation.

Question 20:
Why are budding, fragmentation and regeneration, all considered to be asexual type of reproduction ?
Solution :
Because all these methods involves a single parent for the production of a new organism, without the involvement of gametes.

Question 21:
Fill in the following blanks with suitable words :
(a) The process of………ensures continuity of life on earth.
(b) Plasmodium reproduces by the process of……..fission whereas Paramecium reproduces by the process
of……….fission.
(c) Rose plants and sugar cane crop are usually grown by the………..method.
(d) Vegetative reproduction of potato plants is done by using………..
(e) Strawberry plants are propagated by the natural………..method.
Solution :
(a) Reproduction.
(b) Multiple; Binary.
(c) Cutting.
(d) Tubers.
(e) Layering.

Question 22:
a) What is the basic difference between asexual reproduction and sexual reproduction ?
(b) Which of the following organisms reproduce by sexual method and which by asexual method ?
Amoeba, Cats, Humans, Hydra, Birds
Solution :
(a)
Asexual Reproduction
(i) The offspring arises from a single parent.
(ii) The production of new organism does not involve gametes
Example:- Amoeba, Yeast.
Sexual Reproduction
(i) The offspring arises from two parents of different sexes.
(ii) The production of new organisms involves the use of gametes.
Example:- Fish, Frogs, etc.
(b)
(i) Sexual Method: Cats, Humans, birds.
(ii) Asexual method: Amoeba, Hydra.

Question 23:
(a) What is meant by regeneration ? Name two animals which can regenerate fully from their cut body
parts.
(b) Explain why, more complex multicellular organisms cannot give rise to new organisms through regeneration.
Solution :
(a) The process of getting back a full organism from its body parts is called regeneration. The two animals which can regenerate fully from the cut body parts are ? Planaria and Hydra.(b)In complex multicellular organisms, specialized cells makeup tissues; tissues makeup organs; organs makeup organs systems and finally organs systems makeup organisms. Since complex Multi cellular organisms have a high degree of organisation in their body, they cannot be reproduced from their cut body parts by the process of regeneration.

Question 24:
Explain vegetative propagation with the help of two examples. List two advantages of vegetative propagation.
Solution :
In vegetative propagation, new plants are obtained from the parts of old plants (stems, roots and leaves), without the help of reproductive organs. Example ? Bryophyllum plant reproduces from its leaves and money plant grows from its stem. Advantages of vegetative propagation:- (i) Plants grow faster by the process of vegetative propagation. (ii) They need less care.

Question 25:
(a) What is meant by the term ‘artificial propagation of plants’ ?
(b) Name three common methods which are used for the artificial propagation of plants.
(c) Name two plants which are usually propagated by artificial propagation methods. Name the method of artificial propagation used in each case.
Solution :
(a) The process of growing many plants from one plant by man-made methods is called artificial propagation of plants. (b) The methods used for artificial propagation of plants are:
(i) Cutting
(ii) Layering and
(iii) Grafting
(c)
(i) Rose grows by means of cutting.
(ii) Jasmine grows by layering