Reproductive system

used to characterize egg and sperm cells

Sex cells, Gametes, Reproductive cells or germ cell

homologous pair

chromosomes that look alike and carry the same sequence of genes for the same traits

haploid cell

has only one set of chromosomes

metaphase I

homologous chromosomes/pairs align along middle of the equator called the metaphase plate

anaphase I

homologous pairs/chromosomes are pulled to opposite ends of the equator

telophase I

1. Nuclear envelope reforms

2. Spindle fibers break down

3. Cleavage furrow develops

cytokinesis I

Cleavage furrow continues to develop and split the cell into two daughter cells

prophase II

• Two daughter cell have gone through interphase

• nuclear envelope breaks down

• Centrioles move to opposite ends and spindle fibers attach to the kinetochore of the sister chromatids

metaphase II

Sister chromatids align down the equator called the metaphase plate

anaphase II

sister chromatids are pulled to opposite ends of the equator/poles

telophase II

• Nuclear envelope reforms

• Spindle fibers breaks down

• Cleavage furrow develops

cytokinesis II

• The daughter cells splits into four daughter cells

• We have 23 chromosomes in each daughter cell

Spermatogonia - spermatogenesis stage

sperm stem cells called spermatogonium divides by mitosis to develop two cells (46 chromsomes). One cell is re-used (unlimited bank supply for male sperm development)

1st meiotic division - spermatogenesis stage

• Primary spermatocyte is formed and stage I of meiosis starts

• Secondary spermatocyte is formed at the end of stage of Meiosis I

2nd meiotic division - spermatogenesis stage

• Secondary spermatocyte becomes spermatids after Meiosis II

• Four spermatozoa (sperm cells) are developed

germ cells

from yolk sac migrate to ovary & become oogonia/oogonium

oogonia/oogonium

in female fetus, divide to produce millions by mitosis but most degenerate

atresia

resorption, degeneration

Polar body

small cells which are byproducts from meiosis that forms an egg, and is degraded

testes

• paired oval-shaped glands (gonads) in the scrotum

• secretion of sperm cells; secretion of testosterone

• Surrounded by dense white capsule called tunica albuginea

Seminiferous tubules

• where sperm cells develop

• contains loose connective tissues and made up of Leydig cells and Sertoli cells

Sertoli cells

produces androgen to promote production of sperm cells

Leydig cells

produce testosterone

scrotum

saclike structure which holds the testes

Cremaster muscles

• aids in pulling the testes close to the body and moving them away to keep it cool

• muscle which extends from the abdomen into the scrotum

head - sperm cells

acrosomes; contains enzymes which allows the sperm to penetrate through an egg

Midpieces - sperm cells

• contains the mitochondria

• supplies energy to the sperm

tail - sperm cells

• also called flagella

• helps propel sperm cells into the vaginal canal

epididymis

• Stores and transport sperms to ductus deference

• comma-shaped organ that lies along the posterior border of the testis

epididymis head

stores the sperm until it’s ready to mature

epididymis body

tubes where sperm matures

epididymis tail

portion of the epididymis connected to the ductus deference which transport the seminal vesicle

ductus deference

• Aids in moving sperm away from the epididymis through/to the seminal vesicles to combine with semen

• aka vas deference or sperm duct

• Found in each of the testes

semimal vesicles

• secrete 2/3 of the volume of semen

alkaline

fluid that helps to neutralize acid in the male urethra and female reproductive tract

fructose

for ATP production by sperm

Prostaglandins

contribute to sperm motility and viability

Semenogelin

main protein that causes coagulation of semen after ejaculation

ejaculatory duct

Hollow tubes which serves as a passageway for sperm to travel through the penis to be released

urethra - male

Tube like structure allowing urine and semen to pass through from the bladder and ejaculatory ducts

prostate gland

• Aids in the production of semen

• Prevent urination during ejaculation

• Made up of smooth muscles

penis

contains the urethra and is a passageway for the ejaculation of semen

glans

the head of the penis, opening of the urethra

Corpus cavernosum

columns of tissues which fills with blood to cause an erection

Corpus spongiosum

spongy tissue which fill with blood to cause an erection

bulbourethral gland

• Responsible for producing pre-ejaculate

• cleans and lubricate the urethra prior to semen being released

• Neutralize the acidic environment from urine

semen

• combination of sperm cells and other secretions

• pH around 7.2-7.8

Perineum

thin layer of skin area between the anus and the scrotum

luteinizing hormone

• stimulates Leydig cells to secrete testosterone

• enzyme in prostate & seminal vesicles

follicle stimulating hormone

• stimulates spermatogenesis

• with testosterone, stimulates sertoli cells to secrete androgen-binding protein (keeps hormone levels high)

testosterone

• stimulates final steps of spermatogenesis

• controls the growth, functioning, and maintenance of sex organs

• stimulates bone growth, and sperm maturation

• stimulates development of male secondary sex characteristics

ovaries

paired glands where eggs are produced

Suspensory ligaments

connects each ovary to the sidewalls of the uterus

Ovarian ligaments

connects each ovary to the lateral side of the uterus

Fimbriae

moving finger-like processes

Ovarian follicle

functional unit for the female RS, and each one contains an oocyte

FSH - female

hormone which stimulate the ovarian follicles and ovulation

luteinizing hormone - female

stimulate the ovarian follicles to release

Progesterone

hormone thickens uterine walls

Gonadotropin releasing hormone

tells pituitary gland to secrete hormone; LH and FSH

Zona pellucida

• glycoprotein which surround the oocytes, allowing for sperm to penetrate through and fertilize

• prevents another sperm from penetrating

produce estrogen

theca and granular cells

Estrogen

tells the uterus to prepare the uterine wall for implantation

Primordial stage

resting follicle, surrounded by simple squamous epithelium, and grows in size to be a primary follicle

Primary stage

formed from primordial and contains an oocyte surrounded by follicle cells (FSH is released to become the secondary follicle)

Secondary stage

growing follicle, surrounded by zona pellucida granular cells, theca cell and these secrete estrogen

Graafian stage

growing follicle, where the granular cells thicken, zona pellucida is present
and so is the theca cells, this graafian follicle ruptures to release an oocyte (LH)

Corpus Luteum stage

shriveled graafian cells with no oocyte, which secretes progesterone to thicken the uterine walls for implantation(if fertilized) or the uterine wall will shed