A\(\rightarrow \) Anther. It produces pollen grains which are the male gametes.
B\(\rightarrow \) Style. It provides the path through which the pollen tube grows and reaches the ovary.
C\(\rightarrow \) Ovary. It contains ovules and each ovule has an egg cell / female gamete. It develops into fruit after fertilization.

Sexually transmitted diseases caused by
(i) Virus:
 (a) AIDS (Acquired Immune Deficiency Syndrome)
 (b) Genital warts
(ii) Bacteria:
 (a) Gonorrhoea
 (b) Syphilis
Transmission of such diseases can be prevented by the following ways:
 a) Screening tests for blood donors
 b) Mutually faithful monogamous relationships
 c) Educating people in high risk groups
d) Using condoms etc.

Asexual reproduction is the process of producing new organism from a single parent without the involvement of sex cells. Fission and fragmentation are two different forms of a sexual reproduction.

The period when the rate of general body growth begins to slow down and reproductive tissues begin to mature, is called puberty.
Two changes observed in girls at the time of puberty are:
(i) The breast size begin to increase, 
(ii) Menstruation starts.

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.

Reproduction is the process of producing new individuals of the same species by existing organisms of a species, i.e. parents. The importance of DNA copying in reproduction are as follows:
(i) DNA copying is called DNA replication. In this process, one copy each of replicated DNA will be passed to daughter cells.
(ii) Variations may be introduced during DNA copying. This inbuilt tendency for variation during reproduction forms the basis of evolution.

Water is necessary for all metabolic activities. On the moist bread the spores of bread mold get the much needed water; which is not available on the dry bread. Hence, bread mould grows profusely on a moist slice of bread rather than on a dry slice of bread.

When the colony of yeast is in water, it does not get nutrition, because water does not have nutrients. Sugar, on the other hand, provides nutrition. Once the yeast gets nutrition, it grows and begins producing buds. That is why, colonies of yeast fail to multiply in water, but multiply in sugar solution.

The reasons for adopting contraceptive methods are:
(i) To avoid frequent pregnancies, which in turn helps in population control.
(ii) To prevent the spread of Sexually Transmitted Diseases (STDs).

Functions of testes in human beings include:
(i) production of male sex cells-sperms.
(ii) production of male sex hormone-testosterone.

No, copper-T does not prevent the transmission of sexually transmitted diseases. Copper-T only prevents implantation. The only safe method that can be used to prevent the transmission of sexually transmitted diseases is condoms.

Menstruation occurs when the egg is not fertilised. Every month, uterus prepares itself to receive a fertilised egg. To nourish the embryo, its lining becomes thick and spongy. In case, egg is not fertilised, this lining breaks and discharges out of the body through the vagina in the form of blood. This is referred to as menstruation.