lecture 4 sec 1

most human cells have ___ pairs of chromosomes

23

1-22 chromosomes pairs are called

autosomes

23rd pair of chromosomes are called

sex chromosome

sex chromosomes are either ____ or ____

they must have ___ to survive

XX or XY

X`

all eggs come from ____ so have ____ chromosomes

mom

X

sperm come from ___ so can have either ___ or ___

male

XX XY

what 3 things determine sex

genes, gonads, genetails

define intersex

disparities between the genes, gonads, and genitals

how is gender different from biological sex

it is the psychological sense of sexual identity

another word for primary sex organs

gonads

gonads of male and female

male: testis

female: ovaries

secondary sex organs male and female

male: ducts, glands, penis (deliver and store sperm)

female: uterus, uterine tube, vagina (bring sperm to egg)

external genitalia are withing the ___ body area

perineum

secondary sex characteristics func and apperance

distinguish sexes and attract mates

• appear during puberty

• pubic and axillary

some female sex characteristics

distribution of body fat

finer hair less visible\

enlargement of breasts

some male sex characteristics

facial hair

visible thicker hair

muscular physique

overall func of male repro

make and store sperm

overall func of female repro

union of egg to sperm

holds and feed fetus

gives birth

feeds newborn

what is it called when the fetus has potential to build male or female parts

noncommittal

gonadal ridge location and devolp time

• alongside mesonephros primitive kidney

  • 5 to 6 weeks

mesonephrenic

duct that can develop into male repro tract

paramesonephric

duct that can become female repro tract

SRY

sex determining region or Y

codes for protein TDF

TDF

works with other chromosomes to make androgen receptors and genes for male anatomy development

gonadal ridge turns into

rudimentary testis at 8 weeks and secretes testosterone

testis also secretes

MIF so paramesonephritic duct atrophies

what structure near prostate vestige is left behind

paramesonephric

development of female results from ____ of androgens

absence

what are the identically male and female parts at embryonic stage

genital tubercle

urogenital fold

labioscrotal fold

what does the genital tubercle develop into

glans penis or glan clitrois

what does the urogenital fold develop into

perineal raphe both parts

what does the labioscrotal fold develop into

labia majoria and or scrotum

what is gubernaculum

connective tissue that anchors gonads to floor of abdominopelvic cavity

what is cryptochidism

boys born without testis distended

describe distent of testes in male

begins 6 weeks

superior part of embryonic gonad degenerates → inferior part migrates downwards

7th month testes abruptly pass through the inguinal canals into the scrotu

perineum

space between anus and scrotumsc

scrotum

sac of skin; contains testis

what does scrotums walls contain

thin, pigmented, wrinkled

dartos

smooth muscle: wrinkles skin lessen surface area lowers heat

septum vs raphe

septum divides the scrotum and raphe is the external line

spermatic cord

bundle: contains ductus deferens, vesseks, nerveso

paminiform plexus

venous network countercurrent heat exchange

inguinal canal and what is its hernia

path of low resistance

abdominal content potrude

cremaster

skeletal muscle that raises testis

for sperm production

sperm should be cooler than abdominopelvic cavity

temp regulation

dartos

cremaster

pampiniform

wrinkle skin

elevate

countercurrent heat exchange

testis endocrine because

interstitial cells release testosterone (laydig) and serioli inhibin

testis exocrine because of

sperm release

testis cytocrine because of

sperm cells

tunica albugineea

fibrous capsule

septa

divides lobules

germinal epithelium

sperm production

sertoli cells func

support BTB nurioish aka nurse cells

BTB

protect developing sperm from immune system by tight junctions

germs are diploid and copy by what cell division

one daughter cell undergoes ____ to become sperm

mitosis

meiosis

sperm are made in

seminiferous tubules

sperm leave seminiferous tubules and cilia move them to ____

rete testisre

rete testis bring sperm to _____

efferent ductules

sperm mature and store at

epididymis

what happen to testicular fluid in epididymis

it gets reabsorbed

most sperm take holy long to mature

40 to 60 days

during ejaculation sperm leave the epidiymis and go to ductus deferns and the?

AMPULLA

ductus and smeinal form

ejaculatory duct

accessory ducts

ejaculatory

epididymis

ductus deferens

urethra

seminal vesicles secrete

fructose rich for energy

prostate releases

enzymes for activating sperm

bulbourethral secretes

mucus for lubrication

Gnrh

gonaoropin releasing hormonewhe

re is gnrh release

hypothalamus

what is gnrh target

anterior pituitary

what is gnrh effect

release of fsh and lh

fsh is FSH is _______. It’s released from the anterior pituitary gland. FSH goes to _____cells of testes which release____________) to hold testosterone near developing sperm & _____to regulate hormones and sperm productionwhat and relleased from

follicle-stimulating hormone

Sertoli

androgen-binding protein (ABP)

inhibin

LH goes to where so the ___ cells can release ____

laydig

testosterone

ABP

holds testoterone locally

sperm production needs what hormones

ABP and testosterone

what supresses the secretion of FSH

INHIBIN: released by nurse cells

when sperm drop below ___ mil inhibin levels

5 to 20 million

decrease

what cells in testis reproduce by mitosis

spermatogonia

what are the four phases of prophase

nucleus

chromosome

centrioles

spindle

at mitosis metaphase chromsome are at ____

metaphase plate

first division of meiosis does what

reduces chromosome number se

second division of meiosis does what

splits chromatids

spermatogenisis is making

sperm

mitosis meiosis and spermiogenesis

basement membrane is the boundary of

seminiferous tubule

pprimordial germ cells come from what of embryo and colonized gonadal ___

yolk sac

ridge

spermatogonium are what cells

diploid

type a spermatogonium

undergoes mitosis to make 2 identical daughter cellstyp

type b spermatogonium

enlarges to become primary spermatocyte and is ready for meiosis 1

primary spermatocyte are all

diploid

what happens to spermatocyte at meiosis 1

become secondary spermatocyte

Secondary spermatocyte is ___ ploid, but its chromosomes have ___ #
chromatids. Notice, secondary spermatocyte is smaller than _______
spermatocyte, but larger than spermatids.

haploid

2

primary

secondary spermatocyte undergoes ____

meiosis II which creates 2 spermatids

spermatids are connected by

cytoplasmic bridges

spermatozoon

maturation of cells

how long from type b spermatogonium to mature to spermatozoon

64 days

why does spermatozoon dump most cytoplasm

to reduce mass for motility

nurse cells feed developing ____ and resorb excess cytoplasm shed in ___ proce

spermatids

spermiogenesis

define semen

mixture of sperm and gland fluids

how much volume of semen is released for typical ejac

2 to 5 percent

is sperm a part of semen; what percentage

yes and less than 5 percent