NCERT Solutions for Class 10th Science
Chapter 8. How do Organisms Reproduce
Additional Questions With Solutions
Q1. A couple wants to space the birth of their second child. Suggest one preventive method which could be observed
(a) By the husband (b) By the wife for the same.
Ans: (a) Use of condoms by the husband
(b) Use of oral pills or loop or Copper-T by the wife.
Q2. A girl attains her puberty at the age of 11 years and a boy at 13 years but, still they are asked to refrain from sex, why?
Ans: They are asked to refrain from sex because:-
(i) They are not physically, emotionally mature enough to be able to bear the responsibility of the child.
(ii) They may suffer from reproductive tract infections.
Q3. A pregnant woman visits a doctor to determine the sex of her child. The doctor refused to perform the test. Why is she being denied?
Ans: The doctor refused to perform the test in order to prevent female foeticide which leads to an alarming decline in child sex ratio.
Q4. Blue prints of body design are stored in the DNA. Why?
Ans: The chromosomes present in the nucleus of a cell contain information for inheritance of features from parents to next generation in the form of DNA molecule. The DNA is the information source for making proteins. Thus, blueprints of the body design are stored in the DNA.
Q5. Producing individuals by parents consume a lot of energy. So, why should an individual organism waste energy in the process, it does not need to stay alive?
Ans: Reproduction, unlike other life processes is not essential to maintain the life of an individual organism. But it is essential for providing stability to the population of species.
Maintaining the species is essential for maintaining balance in nature.
Q6. Protozoan reproduce by binary fission as well as by multiple fission. In your opinion which process is better and why?
Ans: Multiple fission is better than binary fission because:-
1. More number of individuals is produced.
2. It helps to tide over unfavourable conditions.