P&A

REPRODUCTIVE SYSTEM

I. INTRO

A. Structures

1. testes, ovaries, and external organs A. many accessory organs involved as well:

Uterus, fallopian tubes, vas deferens, epididymus

B. Function

1. produce sex cells

2. transport sex cells

3. produce & secrete hormones which develop and maintain male and female sex characteristics

II. MALE REPRODUCTIVE ORGANS

A. Main function: to produce sperm

B. Testes

1. 2 ovoid/oval structures found within cavities called SCROTUM

2. Each teste is separated into 250 lobules A. each lobule contains SEMINIFEROUS TUBULES

B. ST contain SPERMATOGENIC CELLS Def: cells that give rise to sperm

C. spermatogenic cells remain inactive until adolescence when they undergo MEIOSIS Def: process of cell division that results in ½ the

amount of chromosomes than the parent cell

Parent cell = 46

Sperm cell = 23 to later combine with egg’s 23

C. Male Internal Accessory Organs 1. Epididymus

S: tightly coiled 6 m. long tube that connects to vas deferens

F: passageway for sperm

2. Vas Deferens S: muscular tube 45 cm. long

Passes along testes, through abdominal cavity, end behind urinary bladder

F: passageway for sperm to urethra

3. Seminal Vesicle S: Saclike structure attached to vas deferens below

urinary bladder

F: secrete fluid that allows for correct pH for sperm to live and sugary substance to energize sperm

4. prostate gland S: chestnut shaped structure surrounding anterior

urethra

F: secrete fluid to help neutralize sperm-cell fluid

5. Semen S: fluid conveyed through male urethra to the

outside of the body via the urethra

1) made of:

Sperm cells from testes

Fluids from seminal vesicle

Fluids from prostate gland

2) 2-6 ml are released at one time

120 million/ml sperm are released

D. Male External Reproductive Organs

1. scrotum A. pouch of skin that holds testes

B. Why? So testes are outside of the body to maintain the correct

temperature for sperm to live and grow

Too hot inside the body

2. penis A. cylindrical organ that houses urethra

B. conveys urine & semen to outside of body

III. HORMONAL CONTROL OF MALE REPRODUCTIVE SYSTEM

A. follicle stimulating hormone – FSH

1. FSH – secreted by anterior pituitary gland

2. stimulate spermatogenic cells to produce sperm

B. Testosterone

1. secreted by testes

2. also stimulates spermatogenic cells to produce sperm

3. secretion is very low until age 13-15

4. Effects: Increased body hair on chest, arm pits, face, pubic

region

Enlargement of larynx

Thicker vocal cords = lower voice

Thicker skin

Increase muscular growth

Broaden shoulders

Narrow waist

Thicker bones

Sperm cells divide and become active

IV. FEMALE REPRODUCTIVE ORGANS

A. Main Function: to produce eggs

B. Ovaries

1. 2 ovoid structures located in shallow depression of pelvic wall

2. s: two regions: Outer cortex

Inner medulla

3. before birth ovaries form several million PRIMORDIAL FOLLICLES A. def: cells that develop into eggs by undergoing

meiosis

B. only 1 million remain at birth 400,000 remain at puberty

Fewer than 1,000 are released during female’s lifetime

4. primordial follicles develop and the OOCYTE (egg cell) inside eventually ruptures out and travels to fallopian/uterine tube Process is call OVULATION

If oocyte isn’t fertilized by sperm it degenerates

V. FEMALE ACCESSORY ORGRANS

A. Uterine/fallopian tubes

S: 10 cm long tubes from ovary to uterus Wall is full of ciliated simple columnar epithelium

to move egg

F: secrete mucous and move cilia to pass egg along tube

B. uterus

1. S: inverted pear shaped Hollow

Muscular

Lower 1/3 called cervix

3 layered wall Endometrium: inner layer

Myometrium: middle muscular layer

Perimetrium: outer covering

F: to hold growing fetus

C. Vagina

1.S: 9 cm long tube from uterus to outside

F: Conveys uterine secretions to outside

Receives penis during sexual intercouse

Transports child during birth

D. labia major

1. S: flaps of tissue seperated longitudinally by a cleft

2. F: to enclose and protect other female reproductive organs

VI. HORMONAL CONTROL OF FEMALE REPRODUCTIVE SYSTEM

* release at about 8 yrs old

A. F:

Develop and maintain female sexual characteristics

Maturation of egg cells

Regulate monthly menstrual cycle

B. FSH & Leutinizing Hormone (LH)

1. secreted by APG

2. control production of sex hormones and egg cells maturation

C. Estrogen & progesterone

1. estrogen A. produced by ovaries

B. controls: Enlargement of accessory organs

Development of breasts and mammary glands

Increase adipose tissue breasts, thighs, and buttocks

Increase vessels to skin

2. progesterone A. produced by ovaries

B. controls uterus changes during menstrual cycle

D. Androgens (male hormones)

1. cause female at puberty to grow hair in arm pits and pubic region

2. the low concentrations cause females to have narrow shoulders and broad hips

VII. FEMALE MENSTRUAL CYCLE

A. DEF:

1. approximate 28 -32 day cycle in which regular changes happen to the uterine wall Usually begins at approx age 13

Culminates in external bleeding

B. hormone involvement

1. FSH & LH cause maturation of egg cells

2. egg cells produce estrogen and progesterone F: responsible to continuing and maintaining female

reproductive system

C. week 1

1. increased estrogen causes endometrium to thicken

D. day 11-14

1. LH causes follicular wall to rupture and egg released = ovulation

* time when woman is most likely to get pregnant

2. follicle without the egg becomes the CORPUS LUTEUM

3. if the egg is not fertilized the CL has no function

E. day 24

If CL has no function, the uterine blood vessels constrict, decreases O2 to uterus

Therefore, uterine lining disintegrates as blood capillaries release blood

F. Day 28-32

1. blood flows out of vaniga

2. lasts approx 3-5 days

3. CL and egg are flushed out

VIII. MAMMARY GLANDS

A. located in subcutaneous tissue of breasts

B. f: secrete milk following pregnancy

C. S: composed of 15-20 lobes with ALVEOLAR DUCTS that lead to the outside