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Question
Answer the following question.
The growing size of the human population is a cause of concern for all people. The rate of birth and death in a given population will determine its size. Reproduction is the process by which organisms increase their population. The process of sexual maturation for reproduction is gradual and takes place while general body growth is still going on. Some degree of sexual maturation does not necessarily mean that the mind or body is ready for sexual acts or for having and bringing up children. Various contraceptive devices are being used by human beings to control the size of the population.
(a) List two common signs of sexual maturation in boys and girls.
(b) What is the result of reckless female foeticide?
(c) Which contraceptive method changes the hormonal balance of the body?
(d) Write two factors that determine the size of a population.
Solution
a) Two common signs of sexual maturation in boys and girls are as follows:
- Broadening of shoulder and chest in boys and development of mammary gland or breast in girls.
- The appearance of hairs on various body parts like the pubic area, armpits, and face.
b) The number of females will become very low in comparison to the males. Hence, there will be a huge imbalance between the male-female ratio in the population.
c) Chemical method of contraception e.g. Oral pills interferes with the hormonal balance of the body.
d) Birth rate and death rate are factors that determine the size of a population.
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