Physiology Ch 20

Front 1

where and how are gametes (sperm or eggs) formed

Back 1

formed in gonads by meiosis

Front 2

each gamete has ______ number of chromosomes (23)

Back 2

haploid

Front 3

the fusion of sperm and egg during fertilization results in _________ zygote with _______ chromosomes

Back 3

diploid; 46

Front 4

XX=

Back 4

female

Front 5

XY=

Back 5

male

Front 6

22 of the 23 chromosomes inherited are __________ chromosomes

Back 6

autosomal

Front 7

the 23rd pair of chromosomes are ________ chromosomes

Back 7

sex

Front 8

true or false:
both sperm and eggs receive random assortment of chromosomes from mother and father during meiosis

Back 8

true

Front 9

all ova contain an ____ chromosome; half the sperm contain _____ and half contain _____

Back 9

X; X and Y

Front 10

what is the gender of the zygote determined by?

Back 10

the fertilizing sperm

Front 11

testis-determining factor (TDF) is located on the _______ chromosome

Back 11

Y

Front 12

the hypothalamus releases _______ and controls release of LH and FSH from the _________ __________

Back 12

GnRH;
anterior pituitary

Front 13

______ and ________ stimulate the production of spermatozoa and eggs and gonadal sex steroids; and maintains size of gonads

Back 13

LH and FSH

Front 14

Sex hormones provide __________ __________ on hypothalamus and anterior pituitary

Back 14

negative feedback

Front 15

gonads also secrete hormones _______ which negatively feeds back on _____________ secretion

Back 15

inhibin; FSH

Front 16

what are the two compartments in the testes

Back 16

1. seminiferous tubules- site of spermatogenesis (gamete production) contains sertoli cells (FSH receptors)
2. leydig or interstitial cells- found in spaces around tubules (LH recptors), testosterone production

Front 17

FSH stimulates ________ ______ to produce spermatozoa and inhibin

Back 17

sertoli cells

Front 18

what is spermatozoa and inhibin

Back 18

a peptide hormones that inhibits FSH secretion

Front 19

LH stimulates ________ ________ to secrete testosterone

Back 19

leydig cells

Front 20

testosterone also targets ___________ ______ in seminiferous tubules to produce _____________

Back 20

Sertoli cells; spermatozoa

Front 21

FSH and LH section high for 1st __________ of life, fall to v. low levels during ______ ______(____________)

Back 21

6 months;
early years (childhood)

Front 22

at puberty, __________ in __________ from hypothalamus

Back 22

increase GnRH

Front 23

the increase in GnRH stimulates an increase in ______ and ______ from the anterior pituitary

Back 23

LH and FSH

Front 24

the increase in GnRH stimulates an increase in ___________ ___________ secretion

Back 24

sex hormone secretion

Front 25

sex hormones drive changes in _______ ____________ ________________

Back 25

secondary sex characteristics (ssc)

Front 26

what is oogenesis?

Back 26

production of female gametes

Front 27

gametes (ova) develop inside:

Back 27

follicles

Front 28

a newborn girl: ovaries have 2 million _______ each inside a primary follicle

Back 28

oocytes

Front 29

once the hit puperty they ovaries will have __________ oocytes

Back 29

400,000

Front 30

reproductive years: each month _______ stimulates 6-12 _______ _________ to develop _______ _________

Back 30

FSH; primary follicles; secondary follicles

Front 31

only one secondary follicle matures into a __________ follicle

Back 31

graafian

Front 32

over a lifetime 400 oocytes are ovulates, the rest undergo _____________

Back 32

apoptosis

Front 33

describe the ovarian cycle

Back 33

-secondary follicles contain vesicles that fuse to form single fluid-filled cavity (antrum)
-fluid in the antrum of secondary follicle has high conc. of estrogen that increases number of FSH and LH receptors on follicle
-follicle grows into mature (Graafian) follicle

Front 34

how many graafian follicles mature and are ovulated? what happens to the rest

Back 34

only one; the rest degenerate (atresia)

Front 35

ovulation is stimulated by a sharp rise in _______

Back 35

LH( LH surge)

Front 36

what stimulates the hypothalamus and anterior pituitary to release more LH

Back 36

high blood estrogen levels

Front 37

describe post ovulation if no fertilization

Back 37

-after ovulation mature follicle becomes corpus luteum an produces progesterone and estrogen
-if pregnancy does not occur CL only lasts for 10-12 days and then breaks down

Front 38

what causes CL breakdown

Back 38

negative feedback

Front 39

cyclic changes in secretion of ______ _______ ____________ ________ cause cyclic changes in ovary

Back 39

anterior pituitary gonadotropic hormones

Front 40

name and describe the phases of the menstrual cycle:

Back 40

1. cyclic changes in ovaries: follicular pahse, ovulation, and luteal phase.
2. cyclic changes in Endometrium: menstrual. proliferative, and secondary phases

Front 41

explain the cyclic changes in the endometrium:
last 28 days and has 3 phases

Back 41

1. menstrual phase: loss of tissue from lining of endometrium (ovaries- follicle phase)
2. Proliferative phase: growth of endometrial glands caused by elevated estrogen levels (ovaries- luteal phase)
3. Secondary phase: secretion by endometrial glands caused by elevated estrogen and progesterone levels. continue as long as corpus luteum intact and producing progesterone and estrogen

Front 42

blastocyst secretes a hormone-

Back 42

human chronic gonadotrpin (hCG)

Front 43

hCG effects include:

Back 43

identical to LH-
maintains corpus luteum long past time it would normally regress and maintains estrogen and progesterone secretion from corpus luetum; prevents menstruation