Practice question

Capacitation is a final functional maturation occurring only within female reproductive tract fluids of uterus and oviduct after epididymal transit. Albumin acts as cholesterol acceptor, extracting cholesterol from sperm plasma membrane, increasing fluidity and permeability. Bicarbonate influx activates soluble adenylyl cyclase, elevating cAMP, stimulating PKA-dependent tyrosine phosphorylation cascades. Membrane remodeling opens CatSper calcium channels, promotes hyperactivated motility and primes acrosomal responsiveness, conferring true fertilizing ability solely after exposure to female environment essential for successful conception, implantation competence and embryonic development initiation.