chapter 46 Flashcards
what is sexual reproduction?
involves egg and sperm to form zygote, most animals use this
how are gametes produced?
meiosis
describe the egg
large and cant move
describe the sperm
small mobile flagella
what is asexual reproduction?
offspring without fusion of egg and sperm, not many use this
what is the process for asexual reproduction?
mitosi
what is budding?
part of animal buds off and forms a new individual, jellyfish, starfish,bacteria, yeast
what is fission?
parents separate into 2 individuals in coral and worms
what is fragmentation?
piece breaks off and it can grow into an adult, flatworms
what is regeneration?
regenerating a part, sea stars
look at difference between fragmentation and regeneration
ok
what is parthenogensis?
egg develops without being fertilized, bees wasps, ants. found in stable environments
what are some pros of sexual reproduction?
gets rid of harmful genes and increases genetic diversity. however more energy is needed
why do animals have reproductive cycles related to changing seasons?
more favorable environmental conditions
what’s with the caribou in greenland?
plants started sprouting earlier and caribou reproduction was late. so the pregnant ones didnt get enough nutrients
what is hermaphroditism?
both fe/male parts. snails rarely mate with themselves.
what is sequential reproduction?
individuals born as 1 sex and change. clownfish.
what is ovulation?
egg released at midpoint maturity
what is fertilization?
egg and sperm meet
what is external fertilization?
egg and sperm meet outside of body, usually in aquatic environments
what is spawning?
release of gonads
what does internal fertilization require?
behavioral interactions and compatible copulatory organs
why is survival of zygotes better in internal fertilization?
eggs are shielded from environment, more parental care
what is the spermatheca?
where sperm is stored during copulation to wait for a favorable environment
look at diff types of uteruses
ok
what is the cloaca?
a common cavity at the end of the digestive tract for the release of both excretory and genital products in vertebrates
what are the seminiferous tubules?
where sperm is produced
what is the scrotum?
where testes are held, maintains cooler temp for optimal sperm production
what is the epidiymis?
tube from seminiferous tubules and testes, matures during this 3 week travel
what is ejaculation?
sperm is propelled from each epididiymis through the vas deferens
what is the urethra in males?
outlet tube for both excretory and reproductive system
what is semen?
fluid that allows sperm to get to egg
what are the purpose of the seminal vesicles, prostate gland, and bulbourethral gland?
secretes fluid that mixes with sperm to make semen
what does the seminal vesivcles secrete?
seminal fluid
what does the prostate gland secrete?
prostate fluid that doesn’t make semen gloop up and provides nutrition
what does the bulbourethral gland do?
secretes mucus that neutralizes the acidic urine
what is the baculum?
penis bone that helps make it firmer ;)
what are the glans?
head of penis
what is the prepuce?
foreskin
what is the human penis made of?
3 cylinders of spongy erectile tissue, fills with blood from arteries and pressure seals off veins that drain penis.
what are ovaries?
produce females gametes and reproductive hormones
what are follicles?
contains a developing oocyte and secretes estrogen
what are oocytes?
a partially developed egg
what is the oviduct? (fallopian tube)
tube from ovary to uterus
what is the uterus?
the womb LMAO WHAT KINDA DEF
what is the endometrium?
inner lining of uterus, richly supplied with blood vessels
what is the cervix?
opens into vagina
what the vagina?
location for sperm deposits
what is the vulva?
collective term for female genitalia
what is the labia majora?
encloses and protects the rest of the vulva
what is the labia minora?
thin skin folds that surrounding opening of vagina and urethra
what is the hymen?
a thin piece of tissue that partly covers the vaginal opening
what are mammary glands?
small sacs of epithelial tissue that secrete milk
what is gametogenesis?
production of gametes
what is spermatogenesis?
formation and development of sperm, continuous and millions form a day
what is oogenesis?
development of mature eggs. immature eggs form in the ovary but do not complete develop in years or decades
what are the differences between spermatogenesis and oogenesis?
- sperm is continually produced while there are long pauses in oogenesis
- sperma. is through adolescnce and adulthood while oogen. is completed before birth and stop at age 50
- sperma. use all 4 products of meiosis become sperm while in oogen. cytoplasm goes into one egg who becomes the “the one” and gets released
what is the gonadotrophin-releasing hormone?
directs the release of FSH and LH from the anterior pituitary
what are FSH and LH?
regulate gametogensis and production of sex hormones
what are trophic hormones?
regulaates endocrine cells
what are gonadotrophs?
male and female gonads, stimulate sex hormone production
what are sertoli cells?
nourish developing sperm located in seminiferous tubules
what are leydig cells?
produce testosterone in connective tissue, promote spermatogenesis
what does testosterone regulate?
gonadotrophin-relasing hormone, FSH and LH
what does seratoli cells regulate?
secrete inhibin to reduce FSH secretion
when does ovulation occur?
after endometrium has started to thicken and develop a rich blood supply, preparing the uterus for an implantation of an embryo
what is menstruation?
endometrium is shed
give me the steps of the ovarian cycle lmao
- GnRH is secreted and stimulates anterior pituitary
- FSH and LH are secreted
- FSH stimulates follicle growth
- cells of the growing follicle make estradiol
- estradiol secretion rises steeply
- FSH and LH increase
- maturing follicle forms a bulge at the end of the ovary
- LH stimulates the leftover follicular tissue to make a corpus luteum
give me the steps of the menstrual cycle lol
- estrdiol and progesterone secreted by the corpus luteum stimulate development of uterine lining
- ovarian hormone levels drop and endometrium sheds
what is endometeriosis?
some cells of the uterine linging migrate to an abnormal (ectopic) location
what is menopause?
the end of ovulation and menstruation, ovaries lose responsiveness to FSH and LH->decline in estradiol production
why is menopause unusal?
most animals reproduce for life
what is the grandma hypothesis?
ovulation and menstruation stops so you can help your kids with their kids
who are the only mammals with menstrual cycles?
humans and some primates
what is the estrous cycle?
uterus reabsorbs the endometrium and no fluid comes out. sexual activity is limited.
give me the steps of the formation of a human zygote hehe
- ovulation releases an oocyte
- fertilization occurs in oviduct
- cleavage of zygote
- cells reach uterus and becomes a blastocyst (hollow ball of cells)
- blastocyst implants itself into the endometrium
why is the first trimester have the most radical change in the baby and mom?
more hormones are being secreted
what does human chorionic gonadotropin do?
secretes estrogen and progesterones, detected in pregnancy tests
do all embryos develop?
no some have abnormalities
what is an ectopic pregnancy?
fertilized egg attaches to fallopian tube
where does the developing embryo get nutrients?
for the first 3 weeks-> endometrium
after-> umbilical cord
what is the trophoblast?
outer layer of blastocyst, interacts with endometrium
what is the placenta?
house of fetus, gas exchange, fights infection, food
what is the difference between identical and fraternal twins?
identical twins come from 1 egg and sperm and the embryo splits within the first month
fraternal twins come from 2 eggs and sperm and are in separate placentas
what is organogenesis?
development of organs in the 1st trimester
when does the baby heart start beating?
4 weeks and detected at 10 weeks
when is it called a fetus?
at 8 weeks when all major structures of the adult are present in rudimentary form
how big is the embryo at the end of the 1st trimester?
5 cm long
what happens to the mother during the 1st trimester?
high levels of progesterone, mucus plugs cervix to prevent infection, placenta breast and uterus grow, ovulation and menstrual stop. morning sickness.
what happens during the 2nd trimester?
mother feels fetal movement, hCG secretion declines, corpus luteum deteriorates, placenta takes over the production of progesterone
what happens during the 3rd trimester?
fetus grows and fills the space within the embryonic membrane. mom’s organs get squished
what is labor?
contractions that push baby and placenta out, regulated by oxytocin and estradiol (positive feedback)
what are the 3 stages of labor?
- dilation of cervix
- fetus exiting
- placenta exiting
what is lactation?
production of milk
prolactin-glands to produce milk
oxytocin- produce milk
what is the role of the immune system during pregnancy?
it relaxes. if it were active, it would try to get rid of the baby
what is contraception?
deliberate method to prevent pregnancy
what are the 3 categories of contraceptives?
- preventing the release of egg and sperm (birth control, vasectomy)
- keeping egg and sperm apart (abstinence, condoms, spermicides)
- preventing implantation of embryo (plan b)
what is abortion?
ending of a pregnancy after implantation
what is a miscarriage?
spontaneous abortion
what is the surgical method of abortion?
remove fetus out of uterus
what is the medicinal method of abortion?
blocks progesterone receptor in uterus
