Chapter 45 and 46 - Reproductive Hormones and the Endocrine System/Animal Reproduction Flashcards
what are the 2 main strategies organisms use to reproduce?
1.) asexual
2.) sexual
asexual reproduction
no gamete fusion needed (egg and sperm not needed), “reproduces” via mitosis
fission
splitting yourself in half via mitosis
(ex: amoeba)
budding
outgrowth
(ex: hydras bud out, like a plant growing another leaf)
parthenogenesis
reproduction but without fertilization (there are eggs but no sperm)
fragmentation
regrowing after being “cut up”
(ex: starfish)
sexual reproduction
fusion of gametes (egg and sperm needed) via meiosis
external fertilization
(ex: salmons use external fertilization, female lays eggs, males come fertilize them)
internal fertilization
im not explaining this one :D
hermaphroditic
the individual has both male and female reproductive systems
(ex: nudibranch)
gonads
sperm/egg producing organs
male = testes
female = ovaries
what ploidy are pre-sperm cells?
diploid (2n)
what ploidy are sperm cells?
haploid (n)
how many sperm cells can come from 1 pre-sperm cell?
1 pre-sperm cell (2n) = 4 sperm cells (n)
follicle
a small fluid-filled sac in the ovary that contains one immature egg
born with less than a million follicles (fixed #) but only 100s are used
one follicle gets chosen and lets out an egg every month
oocyte
egg cell
where are follicles located?
in the ovaries
what controls the female reproductive cycle?
hormones
ovarian cycle
controls growth/release of egg, controls ovulation
part of the menstrual cycle
where does the ovarian cycle occur?
ovaries
ovulation
growth and release of egg
follicle stimulating hormone (FSH)
stimulates the follicle to grow
luteinizing hormone (LH)
its peak triggers ovulation
menstrual cycle
prepares uterus for embryo implantation
where does the menstrual cycle occur?
uterus
what are the hormones in the menstrual cycle? what do they do?
estrogen and progesterone
they regulate the menstrual cycle, thicken the lining (endometrium) of the uterus to prepare for pregnancy
what does birth control do?
progesterone hormone: (+)
esterogen hormone: (–)
fools the body into thinking its pregnant, stops/reduces ovulation, thickens cervical mucus to keep sperm from entering the uterus, and thinning the lining of the uterus so that a fertilized egg is less likely to attach
describe the process of the female reproductive cycle?
1.) hypothalamus is stimulated by high levels of estrogen, then inhibited by a combination of estrogen and progesterone
2.) hypothalamus releases hormones to the anterior pituitary gland
3.) anterior pituitary gland releases follicle-stimulating hormone (FSH) and luteinizing hormone (LH) into the bloodstream
4.) FSH and LH starts the ovarian cycle
growing follicle => mature follicle => ovulation => corpus luteum (remaining bits of the follicle) => degenerating corpus luteum
5.) growing follicle secretes estrogen, remaining bits of the follicle secretes progesterone and estrogen
6.) levels of ovarian hormones in the blood
(–) estrogen and progesterone => triggers menstruation
(+) estrogen peak causes LH to (+)
(+) estrogen and progesterone => promotes thickening of endometrium
endometrium
mucous membrane lining the uterus
“fast block”
caused by membrane depolarization when the sperm binds
acrosomal enzymes
enzymes secreted by the sperm that digest the jelly coat surrounding the egg
“slow block”
involves calcium signaling to cause fertilization envelope lift-off
describe the process of a sperm fertilizing an egg?
1.) sperm squeezes through cells left over from follicle
2.) sperm’s acrosomal enzymes digest the jelly coat surrounding the egg
3.) plasma membranes of the sperm and egg fuse
4.) sperm nucleus enters the egg cytoplasm
5.) sperm and egg chromosomes intermingle
true or false: development involves repeated cell division and cell migration
true
what are the stages of development? describe them
1.) fertilization = sperm fertilizes egg
egg => zygote
2.) cleavage = 1 cell becomes many cells via mitosis
zygote => blastocyst
3.) gastrulation = cells migrate/fold inwards, creating tissue layers
blastocyst => gastrula
4.) organ formation = organs take shape
identical twins (monozygotic)
when 2 cells split and develop independently
product of a single fertilization
non-identical twins (dizygotic)
when 2 separate eggs are released and 2 separate sperm fertilize the eggs
how does the embryo implant into the uterine wall? describe the process
1.) ovulation releases secondary oocyte
2.) sperm fertilizes ovum, forming a zygote
3.) cleavage of embryo starts
4.) embryo develops into a blastocyst
5.) blastocyst implants in the endometrium
ectopic pregnancy
embryo does not travel to the uterus
true or false: life support system is established in the 1st month
true
allantois
part of the umbilical cord
placenta
an organ that allows fetal-mother exchange, provides nourishment and oxygen, and releases waste
what is in vitro fertilization (IVF)? describe how it works
external fertilization, manual
collected sperm and egg => in vitro fertilization on plate or something => egg becomes zygote => zygote becomes early embryo => embryo implanted into the body
true or false: development involves repeated cell division and cell migration
true
