Chapter 1: How Do Organisms Reproduce?- Exercise- 2

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Chapter 8: How Do Organisms Reproduce?

Class: X

Exercise number 2

 

Question 1:

How does binary fission differ from multiple fission?

Answer 1:

Question 2:

How will an organism be benefited if it reproduces through spores?

 

Answer 2:

Following are the advantages of an organism reproducing through spores.

 

1. Large numbers of spores are produced in one sporangium.
2. Spores are distributed easily by air to far-off places to avoid competition at one

place.

3. Spores are covered by thick walls to prevent dehydration under unfavourable conditions.

Question 3:

Can you think of reasons why more complex organisms cannot give rise to new individual through regeneration?

 

Answer 3:

 

In a Complex organism, different tissues and organs have entirely different structure, which can be used for the growth of lost body parts e.g., skin, blood etc., but it can’t be used for an individual regeneration.

 

In contrast to the above, in Simple organism regeneration happens through Mitosis, in which a particular type of tissue can give rise to its own kind only. This is because of the similar kind of cell structure of their entire body.

 

 

Question 4:

 

Which of the following is a plant hormone?

1. Cytokinin
2. Insulin
3. Thyroxin
4. Estrogen

 

 

Answer 4:

 

1. Cytokinin

 

Question 5:

Why is DNA copying an essential part of the process of reproduction?

 

Answer 5:

 

DNA (Deoxyribonucleic acid) carries the basic genetic characteristics from parents to the offspring. DNA also contains proteins which control all the functions and structure of an individual. DNA copying is very important during reproduction or else the characteristics of genes will not be carried from one generation to the next and offspring will be entirely different from parents.