SPANGLER SCIENCE

Reproductive System
HOME
Textbook Online
SCIENCE SCHEDULE
GRADES & CURRICULUM
UNITS OF STUDY

Class Notes

FUNCTION:

Reproduction of species.


STRUCTURE: 

MALE

Testes- endocrine syst. - hormone testosterone for 2ndry sex characteristics.

    reproductive syst.- sperm for reproducing species. (2)

*area sperm developed (from puberty, 200million per day)

Sperm- 3 parts: 1. head- chromosomes, DNA. 2. Middle piece-mitochondria. 3. tail- mobility. Microscopic, .002 inches.

- if testes remain inside the body then there are no fertile sperm, can not reproduce.

Epididymus- coiled tube across the top of the testes (18ft long)

stores sperm 2-3 weeks. let’s sperm mature.

Scrotum- skin sac, pouch, that carries the testes.

keeps the testes 2-3 degrees cooler than the core of the body (98.6) for sperm development. 

Vas deferens-(tube) connects the epididymus to the urethra.

adds fluid from 3 accessory glands to the sperm to create semen.

-valve allows semen or urine into the urethra at one time.

Urethra-(tube) carries the semen outside of the body through the penis.

also carries urine out of the body.  *never both at same time.

Penis- contains the urethra. made of erectile tissue that has many blood vessels that cause elongation (lengthening) and stiffening, or erection.

Glans- sensitive tip of penis covered by foreskin, removed by circumcision. Middle- space for blood flow;

Accessory Glands- fluid from 3 glands contribute to seminal fluid (plasma) to combine with sperm to form a mixture called semen.

1. seminal vesicles- contribute 70% of fluid, provides energy to the sperm.

2. prostate gland- contribute 30% of fluid, provides stimulant to sperm to lash their tails.(movement)

3. cowper’s gland- contribute less than 1% of fluid, provides lubrications and buffers the urethra.



FETAL DEVELOPMENT SITES:

PPT- Spangler/Monthly Steps

Pregnancy Slide Show

Female Reproductive Tutorial

Male Reproductive Tutorial

Fertilization Video (YT)

Fetal Dvlpmt - by weeks

Fetal Dvlpmt - by months

fetal dvlpmt - text only (+cell division video)

baby center fetal development

fetal dvlpmt - by trimesters

FEMALE:

Ovaries- located at hip level; size and shape of almond.

-attatched to uterus by ligaments.

-holds eggs, ovum-one egg; ova-more than one egg, for reproduction.  Each ovum contains 23 chromosomes, DNA in the nucleus. At birth has 400,000 undeveloped (unripened) eggs; about 500 eggs mature and leave. One egg at a time matures and leaves an ovary; the ovaries take turns inovulation so that one month will come from one ovary and the next month the egg will come from the other ovary. Eggs begin to mature at puberty until menopause.

- also produces endocrine hormones, progesterone and estrogen for 2ndary sex characteristics. 


Fallopian tube- (oviduct) not connected to the ovaries.

-tube that brings the ovum to the uterus, about 4-5days travel.

-lined with cilia(tiny hairs) that creates current to sweep ovum towards the uterus.

-usually  where the sperm meets and fertilizes the egg.

Uterus- (womb) size and shape of pear.

-has thick muscular walls so it can expand for a growing baby.

-walls lined with endometrium that thickens each month with blood to prepare for fertilized egg. If a fertilized egg, zygote, appears it inbeds itself into the lining of the uterus. If no fertilized egg appears then the egg and lining of the uterus shed, menstration.

-cervix- neck or opening of the uterus, contains mucous that kills bacteria.

Vagina- (birth canal) muscular tube that leads outside of the body.

-receives sperm during intercourse.

Outside Area-

1.Labia- external folds for protection of the female reproductive system.

2. Clitoris- sensitive projection of tissue in front of the urethral opening between the labia folds.

3. Hymen- thin membrane circling opening of vagina.

4. Urethral  opening- opening from the urinary system from the bladder. In front of the vaginal opening.


Menstrual Cycle- avg. 28 days  (varies by hormones ) (also irregular at beginning-puberty)

-maturation of egg (ovum)

-phase 1: menstral flow-release of blood tissue and unfertilized egg. lasts about 5 days.

-phase 2: hormones sent out, thickening of uterus occurs. One egg matures and released,ovulation, avg. day 14.

-pregnancy if egg is fertilized by sperm within 48 hrs of ovulation.

-phase 3: uterus wall continues to thicken. if fertilized egg-nourished in lining of uterus. if unfertilized egg- hormones decrease and lining deteriorates=menstrtion begins.


*Endocrine hormones begin menstration avg. age 10-14 (can vary) ovaries begin to mature and release eggs. When hormones decrease avg. age 50-60 (can vary) ovaries stop releasing eggs- menopause.


*PMS- premenstral syndrome- last 7-10 days of cycle, just before menstration occurs. Some state real and others refute it. Stated conditions of cramping, headaches, breast tenderness and fluid retention. Cause is unknown, some guess hormonl changes. 








W.T. EICH INTERMEDIATE