class 10 how does organism reproduce
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Question.6
“Variations that confer an advantage to
an individual organism only will survive in a population.” Justify.
Answer. It is because the chances of survival depend on
the nature of variations and different individuals have different kinds of
advantages.
For example, a bacteria that can withstand heat will survive better in a heat
wave, i.e. the organisms that are fit in the competitive environment and with great
variations will be able to survive and adapt. Thus, more offsprings and
population with genetic variations will survive.
Question.7 Name one sexually transmitted disease
each caused due to bacterial infection
and viral infection. How can these be prevented?
Answer. Sexually transmitted disease caused due to
(i) Bacterial infection is gonorrhoea, and
(ii) Viral infection is AIDS (Acquired Immune
Deficiency Syndrome). These diseases can be prevented by responsible sexual
behaviour such as use of condom during intercourse, etc.
Question.8(a) In the human body what is the role of
(i) seminal vesicles, and (ii) prostate
gland?
(b) List two functions performed by
testis in human beings.
Answer. (a) The role of seminal vesicles and the
prostate gland are as follows:
(i) Seminal vesicles produce seminal plasma
which is in the form of fluid makes the transport of sperms smooth.
(ii) Prostate gland secretes prostatic fluid
that keeps the sperms alive and helps them to swim vigorously.
(b) Two functions performed by the testis
in human beings are as follows:
(i) Formation of sperms takes place in testis.
(ii) They secrete the hormone testosterone which
regulates the formation of sperms and brings changes in the appearance of boys at
the time of puberty.
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