1. The Human Body: The Reproductive System
Biology
Mrs. Bauer

2. Review
Mitosis is the type of cell division that occurs in non-reproductive cells.
Produces exact copies of the parent cell
Meiosis is cell division that occurs in reproductive cells; gametes.
Produces egg and sperm cells with half the genetic material of the parent cells.
23 chromosomes are contained in gametes; this is so that when egg and sperm meet, they produce offspring with 46 chromosomes.

3. Organs of the Male Reproductive System
Penis
Urethra
Vas Deferens
Scrotum
Testes

4. External Organs of the Male Reproductive System
Penis: the external reproductive organ, urethra passes through the penis and allows urine and semen to exit the body.
Scrotum: a sac or pouch which holds the testes.
The function of the scrotum is to maintain the proper temperature of the testes.
Sperm is destroyed unless a temperature of 97o is maintained.

5. Internal Organs of the Male Reproductive System
Urethra: a tube which allows urine and semen to exit the body. Connects to the bladder
Vas deferens: a tube which connects the testes to the urethra and allows semen to exit the body.
Testes: two glands which produce sperm and hormones (testosterone)

6. Secondary Sexual Characteristics - Male
Produced by testosterone
Deeper voice
Chest and facial hair
Lengthen bones
Sperm production
Mrs. Degl

7. Organs of the Female Reproductive System
Vagina
Cervix
Uterus
Fallopian Tubes
Ovary

8. Organs of the Female Reproductive System
Vagina: also called the birth canal, a tube leading from the uterus to the outside of the body.
Cervix: the lower portion of the uterus; where the vagina and uterus meet.
Uterus: a hollow, fist-sized organ located between the bladder and rectum.
Fallopian Tubes: also called oviducts; are two tubes connecting the uterus with the ovaries.

9. Organs of the Female Reproductive System
Ovaries: small organs on the ends of the Fallopian tubes responsible for the production and release of eggs (ova-pl).
Females are born with all of the eggs they will ever produce.
Ovaries alternate the release of eggs each month.
Like testes, the ovaries produce hormones-estrogen.
This release of the ova is called ovulation.

10. The Menstrual Cycle
After menstruation, the ovaries release hormones that tell the uterus to grow a new lining and prepare to receive a new egg.
As the uterus prepares a new lining, one of the ovaries releases an egg. This is called ovulation.
The egg travels through the Fallopian tube. If it is not fertilized it breaks down and is released with the lining and blood of the uterus.
Ovulation occurs about halfway through a woman’s cycle.

11. The Menstrual Cycle and Fertilization
If the egg is fertilized by a sperm cell, the egg will implant in the lining of the uterus and begin to develop.
Zygote: The first cells of a new organism; the time from fertilization to implantation.
Embryo: The zygote is called an embryo from implantation to 8 weeks.
Fetus: After 8 weeks of development, the embryo is known as a fetus.

12. Secondary Sexual Characteristics - Female
Induced by Estrogen
Widen pelvis
Enlarge mammary tissue (breasts)
Begin menstrual cycles
Induced by increased LH, FSH, estrogen, and progesterone hormone levels
Mrs. Degl

13. Fertilization Occurs in upper 1/3 of Fallopian tube
Only 1 sperm can fertilize an egg
Fertilized egg = zygote
An average woman is pregnant (gestational period) for 9 whole months. That is 40 weeks. Babies can survive if they are born earlier, but they may have complications due to being premature.
Mrs. Degl

14. Implantation Fertilized eggs are implanted into thick walls of uterus
Chorion membranes dig into uterus to form placenta
Zygote grows into an embryo
Embryo gets air and nutrients through the umbilical cord
Once pregnant, progesterone levels stay high in mom
Mom’s uterus grows with the baby
Mrs. Degl

15. 1st Trimester = 1st 12 weeks Heart develops first Neural tube develops
All body systems appear by Week 8 – Now a Fetus
Mrs. Degl

16. 2nd Trimester = up to 24 weeks
Most growth
Looks more like a baby
Some preemies survive at this stage
Mrs. Degl

17. 3rd Trimester = Up to 40 weeks
More growth
Kicking, rolling, stretching
Eyes open – Week 32
Lungs mature
Rotates to head-down
position, unless baby is breech
Mrs. Degl

18. Birth Labor Uterine contractions begin Cervix dilates to 10 cm. Birth
Uterus pushes baby through vaginal canal
Placenta delivered after baby
Cesarean Section (c-section) is a surgery that cuts through the uterus to deliver the baby if it cannot be born naturally
Mrs. Degl