Reproduction Flashcards
What does sexual reproduction increase?
genetic diversity
Does asexual reproduction require meiosis or mitosis?
mitosis
What is parthenogenesis?
when females have the ability to make offspring from unfertilized egg
Can some organisms do both sexual and asexual reproduction?
yes
What are hermaphrodites?
organisms that have functioning ovaries and testes
What are simultaneous hermaphrodites?
make both eggs and sperm at the same time
What are sequential hermaphrodites?
change sexes
What are protogynous?
organisms that start as female but become male
What is are protandrous?
organisms that start as males but then become females
What are three internal fertilization strategies?
- oviparous
- ovoviviparous
- viviparous
What does oviparous mean?
egg fertilized inside body, but develops outside of body (think chicken laying eggs)
What does ovoviviparous mean?
fertilized eggs stay inside mother during development and gets food from eggs, BUT there is a live birth
What does viviparous mean?
young develop in mom and are fed by blood
Do both male and female reproductive systems make LH and FSH?
yes
Where is sperm made?
seminiferous tubules of testes
Where is sperm and matured?
epididymis
What carries sperm into the body?
vas deferens
What do the seminal vesicles and bulbourethral gland do?
make fluids that sperm mixes with to get nutrients and make semen
Where does semen exit?
through the urethra in the penis
What is spermatogenesis?
synthesis of sperm
Do sperm need to be cool or hot when developing in the testes?
cool
What cells support sperm?
sertoli cells
What are spermatocytes?
cell undergoing meiosis
What are spermatozoa?
mature sperm
How many mature sperm are made in one cycle of meiosis?
4
What are the 4 distinct sperm parts?
- head
- acrosome cap
- mitochondria
- flagella
What is the acrosome cap?
it contains digestive enzymes that digest the outer coating of the ovum
What cell does LH target in males?
the leydig cells
Where are the leydig cells located?
in the testes
What does LH do to leydig cells?
it tells the cells to secrete testosterone
What does testosterone do to the anterior pituitary gland and stertoli cells?
it inhibits the GnRH stimulating the pituitary gland (so it stops further secretion of LH) and it stimulates the sertoli cells
What is the role of testosterone?
maintains secondary sex characteristics
What does FSH target in males?
sertoli cells
Where are the sertoli located?
testes
What does FSH do to sertoli cells?
triggers stertoli cells to secrete inhibin to inhibit anterior pituitary gland AND make sperms
Do LH and FSH levels remain constant in males?
yes
What does the ovary do?
gland that makes hormones and oocytes
What is an oocyte?
cell in ovary that hasn’t undergone meiosis
What is an ovum?
mature egg cell
What is the fallopian tube?
transports egg to uterus
What is the uterus?
where implantation will occur if egg is fertilized
What is the cervix
muscle that holds uterus closed (opens when baby is about to be born)
What is the vagina?
where sperm is deposited and this opens when baby is about to be born
About how many eggs does a human fetus have?
1 M
Why are oocytes held at arrest?
this happens because the individual has not reached puberty yet, when she does, LH will take the oocyte out of arrest
What what stage are the oocytes held at arrest?
prophase 1
What are graafian follicles?
the eggs that get to go through ovulation
What are secondary oocytes?
eggs that come out of the ruptured follicle
What is the corpus leutem?
the remainder of follicle left when secondary oocyte is released into the fallopian tube
When does meiosis 2 happen?
ONLY if egg is fertilized by sperm
What is ovulation?
when mature egg is released from the ovary
What is the difference between ovum and secondary oocyte?
an ovum is a mature cell that undergoes meiosis 2 while oocyte is immature and doesn’t go through meiosis 2
What is the role of FSH in the female reproductive organs?
stimulates growth of eggs and follicles in ovary
Are larger eggs more or less dependent on FSH?
less dependent
What does LH do in the female reproductive system?
triggers the release of egg from ovary and leads to the luteal phase
What does the corpus lutem secrete and why?
progesterone and estrogen to prepare endometrium
Why does the corpus lutem eventually die off?
because increased levels of progestrone and estrogen inhibits LH and FSH which the corpus luteum needs to survive
How does menstruation occur?
corpus luteum stops sustaining endometrium (with progesterone and estrogen), the lining starts to shed
What is proliferation?
when the endometrium starts building back up again
What is secretion?
corpus lutem secretes estrogen and progesterone to thicken lining for implementation
