Number of oocytes at bih ?

Ans. is 'a' i.e., 2 million In humans, no new ova are formed after bih. During fetal development, the ovaries contain over 7 million primordial follicles. However,-many undergo atresia (involution) before bih and others are lost after bih. At the time of bih, there are 2 million ova, but 50% of these are atretic. The million that are normal undergo the first pa of the first meiotic division at about this time and enter a stage of arrest in prophase in which those that survive persist until adulthood. Atresia continues during development, and the number of ova in both of the ovaries at the time of pubey is less than 300,000.