CBSE Class 10 Answered

Typically females are born with around 2 million unripened ova or eggs. No more are formed and added after birth. A large number of these eggs degenerate during the phase from birth to puberty.  Females retain approximately 200,000 eggs into puberty. Of these around 400 eggs complete meiosis and may be ovulated. Each month during the menstrual cycle, an egg will ripen and be released by the ovary. This phenomenon is called ovulation. Unlike the male sperm cells and other cells of the body, these original ova are never replaced by new cells

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