("Pause" means stoppage and "meno" stands for menstrual cycle).Thus, it refers to physiological stoppage of menstrual flow. It occurs between the age of 45-50 years, due to decrease in female sex hormone production (viz. estrogen). It also marks the termination of follicle development in the ovaries and the end of child bearing period.
Some terms associated with reproductive system:
Placenta: the special connection through which the exchange of materials, food, etc). oxygen, CO₂, waste mateirals, food, etc.) between fetal and maternal circulations occurs. It's also known as after-birth.
Parturition: ("part" = separate or more away) Separation of foetus from the uterine wall of the mother, i.e., act of giving birth to young foetus.
Gestation: The period of development from fertilisation to birth is known as gestation.
Parthenogenesis (" virgin birth"): It is the development of an organism without fertilisation. In some species, eggs can develop on their own, when stimulated without fusion with the sperm.
This development of an unfertilised egg into an adult is known as parthenogenesis, e.g., plant lice, thrips, ants, bees, wasps, etc.
Jacques Loeb demonstrated that some animals viz, sea urchins, frogs and salamanders can be stimulated to develop by applying external stimuli, which includes pricking, shaking, heating, subjecting to dilute organic acids or high salt solution. This is known as artificial parthenogenesis and many of these animals have been produced by this method, including a rabbit.
Paedogenesis: It is an act of producing young while in immature or larval state, e.g., certain insects, amphibians, etc. In other words, it is areproduction by sexually mature young or larval animals, usually without fertilisation. This is also known as Neoteny
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