What are the different methods of contraception?
There are various birth control methods which prevent fertilization (meeting of a sperm to ovum to form a zygote) is known as contraception. There are mainly three major types of contraception:-
Temporary methods
Permanent method
Medical termination of pregnancy
Temporary methods:- they contain natural, barrier or physiological methods of the birth control. In natural, Lactation amenorrhea (absence of menstruation) method is used, where there is intense lactation occurs during the absence of periods in females which prevents from the birth control. In barrier methods- condoms, cervical caps, vaults and Intrauterine devices are used for the contraception. Or, in physiological devices oral pills or injections can be taken for the birth control which confirms the ovulation occurance in females by secreting the FSH (follicle stimulating hormone) or LH (Luteinizing hormone).
Permanent method:- it is a surgical method for the birth control. In man it is known as Vasectomy or in females it is known as tubectomy. Vasectomy is the process of removal of short segment of each vas deferens and tying up of the remaining ends tightly with the surgical thread. And tubectomy is the process of removal of fallopian tube and the remaining ends are tied up tightly with the surgical thread.
Medical termination of pregnancy:- also called induced abortion. It is the voluntary termination of a pregnancy before the foetus making. It is done to get rid of unwanted pregnancy, rapes etc.
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Draw a labelled diagram of the longitudinal section of a flower.
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Asexual reproduction takes place through budding in
(a) amoeba.
(b) yeast.
(c) plasmodium.
(d) leishmania.
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Define the principal focus of a concave mirror.
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