Chapter 46 Reproduction

Front 1

4 types of asexual reproduction

Back 1

fission, budding, fragmentation, parthenogenesis (bees, wasps, ants)

Front 2

advantages of asexual reproduction

Back 2

much faster reproduction.
don't need a mate.

Front 3

advantages of sexual reproduction

Back 3

diversity!
the succeeding generation adapt to environmental changes
ability to get rid of harmful genes more readily.

Front 4

reproductive organs

Back 4

GONADS - in both males (testes) and females (ovaries)
- produce gametes
OTHERS - transport gametes.
- house the embryo and fetus.

Front 5

ovaries

Back 5

- female gonad.
- internal
- connected to the oviduct

Front 6

oviduct

Back 6

- female
- internal
- connected to the ovaries
- fertilization happens here

Front 7

uterus

Back 7

- female
- internal
- muscular
- endometrium - interior
- cervix - opening of the uterus. only opens during birth.

Front 8

external features of female reproductive system

Back 8

- vulva - labia
- clitoris

Front 9

testes

Back 9

- male
- internal
- male gonad

Front 10

vas deferens

Back 10

- male
- internal
- sperm transportation
- lead to epididymis

Front 11

ejaculatory duct

Back 11

- male
- internal
- delivery of sperm from seminal vesicle
- runs through prostate

Front 12

urethra

Back 12

- urine transport

Front 13

external features of male reproductive system

Back 13

- penis
-scrotum

Front 14

accessory glands of male reproductive system

Back 14

- seminal vesicle
- prostate
- bulbourethral gland

*together they make up semen to allow transfer of sperm*

Front 15

spermatogenesis

Back 15

- happens in the testes
- seminiferous tubules - wound within the testes. where spermatogenesis happens.
- epididymis - where sperm become motile.
-sertoli cells

Front 16

structure of sperm

Back 16

head- contains nucleus and acrosome which digs.
midpiece - contains mitochondria which makes ATP so that sperm can move.
tail - motility.

Front 17

how a sperm is produced

Back 17

1. germ cell --> (MITOSIS)
2. sperm stem cell --> (MITOSIS)
3. primary spermatocyte --> (MEIOSIS I)
4. 2 secondary spermatocytes --> (MEIOSIS II)
5. 4 spermatids --> (DIFFERENTIATION)
6. 4 sperm cells

Front 18

hormonal control of spermatogenesis

Back 18

- hypothalamus secretes GnRH which stimulates release of FSH and LH from anterior pituitary
- FSH - stimluate production of sertoli cells --> spermatogenesis
- LH - stimulate production of leydig cells --> testosterone

Front 19

FSH role in spermatogenesis

Back 19

- hypothalamus stimulates release of FSH from anterior pituitary.
- activates sertoli cells which are involved in spermatogenesis

Front 20

LH role in spermatogenesis

Back 20

- hypothalamus stimulates release of LH from anterior pituitary.
- activates leydig cells which are involved in production of testosterone.

Front 21

oogenesis

Back 21

- happens in the ovary
- oocyte (pre-egg) develops in a folicle
- after ovulation the follicle becomes the corpus luteum.

Front 22

production of an egg

Back 22

1. germ cell --> (MITOSIS)
2. primary oocyte (present at birth) --> (MEIOSIS I)
3. secondary oocyte
4. ovulation, sperm entry of primary of secondary oocyte --> (MEIOSIS II)
5. fertilized egg

Front 23

ovarian cycle

Back 23

- follicle grows and matures
- ovulation - egg released from follicle. caused by spike in LH which is caused by a spike in estrogen (follicle produces estrogen). happens halfway into cycle.
- corpus luteum forms after egg is released

Front 24

follicular phase of ovarian cycle

Back 24

- follicle grows and secretes estrogen.
- ovulation occurs halfway through cycle.
- ovulation is when the egg is expelled from the follicle.

Front 25

luteal phase of ovarian cycle

Back 25

- corpus luteum's function is to maintain pregnancy
- produces progesterone.

Front 26

uterine cycle

Back 26

- triggered by low estrogen levels.
- 0-5 - menstrual flow - shedding of endometrium. happens because egg is not fertilized.
- 5-14 - proliferative phase - building up of endometrium. preparing for possible pregnancy.
- 14-28 - secretory phase - contiunation and eventual cease of growth of endometrium. stop is caused by slowing progesterone.

Front 27

fertilization

Back 27

- happens in oviduct.
- cleavage
- implantation
- development of fetus

Front 28

cleavage

Back 28

- happens after sperm meets the egg.
- cells divide 24 hours after fertilization. becomes a blastocyst within 1 week.

Front 29

implantation

Back 29

- happens after cleavage of the blastocyst.
- blastocyst --> trophoblast
- implants into endometrium.
- secretes hCG

Front 30

first trimester of pregnancy

Back 30

- 0-3 months
- nutrient acquisition 2-4 weeks from the endometrium.
- trophoblast and endometrium form placenta for nutrient acquisition.
- organogenesis - formation of organs

Front 31

second trimester of pregnancy

Back 31

- 3-6 months
- corpus luteum has disintegrated
- placenta takes over production of progesterone.
- embryo now called fetus
- growth (from 6 to 30 cm in length)
- becomes physically active.

Front 32

third trimester of pregnancy

Back 32

- 6-9 months
- growth (about 50 cm)
- organ maturation.

Front 33

induction of labor

Back 33

- estrogen secreted from ovaries. induces oxytocin receptors on uterus.
- oxytocin stimulates uterus to contract. POSITIVE FEEDBACK.

Front 34

3 stages of birth

Back 34

1. dilation of the cervix
2. expulsion/ delivery of the baby
3. delivery of the placenta

Front 35

contraception

Back 35

- birth control pills - synthetic estrogen and progesterone which mimic negative feedback. blocks GnRH release.
- IUDs
- RU486 - morning after pills. blocks progesterone receptors in uterus.