embryology

what two parts human development divides into

prenatal (before birth) and postnatal (after birth)

where are spermatogonias in fetal and postnatral periods

they are dormant in the seminiferous tubules. they increase in numbers during puberty and after several mitotic divisions, the spermatogonia grow and undergo changes.

spermatogonias transformed into

primary spermatocytes and after meiotic division, forms two haploid secodnary spermatocytes.

what are secondary spermatocytes transformed into

by meiotic division, spermatids are formed.

what are spermatids transformed into and what is this process called

four mature sperms by spermogenesis.

what are sertoli cells

sertoli cells are lining the seminiferous tubules. they are supporting germ cells and may be involved in the spermatogenesis.

where are sperms transported after seminiferous tubules

epididymis.

what is in sperms head and whats covering the head.

haploid nucleus and head is covered by acrosome (containing enzymes).

the tail parts and function of tail

middle, principal and end piece. tail provides the motolity of sperm. middle part contains mitochindria, which provides ATP, for activity.

what oogonia turns into

enlarges and turns into primary oocyte. it is formed before birth and after mitotic division of oogonia in the fetus.

what is primary oocyte surrounded by

follicular epithelial cells, primordial follicle.

what primordial follicles turn into

primary follicle, from squamos cells to cuboidal cells.

primary oocytes meiosis

starts nbefore birth, but stays arrested in prophase 1, before adolscence.

when and in what primary oocyte turns into

secodnary oocyte and forst polar body. just before ovulation

in what phase secondary oocyte is arrested into.

metaphase 2 and waiting for fertilization.

uterine tubes parts

infundibulum, ampulla, esthmus.

what is capacitation

Capacitation is the crucial maturation process sperm undergo in the female reproductive tract, transforming them from incapable to fertilization-ready by altering their membranes, increasing motility (hyperactivation), and priming them for the acrosome reaction (releasing enzymes to penetrate the egg). It involves removing cholesterol and proteins from the sperm head, changing ion flow (like calcium influx), and triggering signaling pathways, allowing the sperm to finally bind to the egg and fertilize it.