Testosterone is secreted by which cell of the testes?
What process does testosterone stimulate in the seminiferous tubules?
Testosterone has what sort of effect on LH and GnRH secretion?
Which hormone, along with testosterone, also stimulates spermatogenesis?
Which hormone reduces FSH secretion by the anterior pituitary and therefore reduces the rate of spermatogenesis?
Name a specific way in which Sertoli cells support Germ cells as they undergo spermatogenesis.
Secrete androgen-binding globulin (ABG) which mops up excess testosterone
Controlling the rate of spermatogenesis
What does dihydrotestosterone do?
Causes expression of male sexual characteristics
What is an acrosome?
Sac, found in the sperm cell head, which contains digestive enzymes
These enzymes break down the outer membrane of the oocyte to help with fertilisation
Sperm cells have large numbers of which organelle?
Why are oocytes much larger than spermatozoa?
Yolk proteins (food source)
tRNA and mRNA
Where is the site of fertilisation?
Ampulla of Fallopian tubes
What happens to the cervical mucus when spermatozoa are detected in the uterus?
Cervical mucus thins
Which type of muscular movements bring the unfertilised oocyte to the ampulla of the Fallopian tubes?
Where do spermatozoa mature?
In the female genital tract
Which process do spermatozoa undergo in the female genital tract before they are capable of fertilising an egg?
Following capacitation, which organelle do spermatozoa use to penetrate the egg?
Fertilisation occurs when which organelles of the oocyte and spermatozoa fuse?
What is the outer membrane of an oocyte called?
Once a spermatozoa has penetrated the zona pellucida using its acrosomal enzymes, what reaction occurs?
What does this reaction prevent?
Zona reaction - zona pellucida becomes impenetrable to any more sperm cells
When a sperm cell penetrates the zona pellucida, the levels of certain ions changes to
a) prevent polyspermy
b) activate the egg.
Which process begins in an oocyte once it has been activated by sperm penetration?
Once an oocyte has been activated, its rate of protein synthesis (increases / decreases).
rate of protein synthesis & metabolism increases
The ___ sperm cell nucleus and ___ egg cell nucleus fuse to form a ___ zygote.
(haploid , diploid)
haploid sperm and egg