1. Human Reproductive System

2. Male Reproductive System

3. Sperm Formation MEIOSIS Form in testes Temperature important! Scrotum: sac that hold the testes Leave testes via epididymus to the vas deferens

4. Semen Fluids help to transport, feed, and protect sperm

5. Secondary Sexual Characteristics - Male Produced by testosterone –Deeper voice –Pubic hair –Chest and facial hair –Lengthen bones –Increased size of testes for sperm production

6. Female Reproductive System

7. Ovum Formation MEIOSIS Ova are formed before birth 1 ovum per month is matured and released from ovaries

8. Secondary Sexual Characteristics - Female Induced by increased LH, FSH, estrogen, and progesterone hormone levels –Pubic hair –Widen pelvis –Enlarge mammary tissue –Begin menstrual cycles

9. Female Menstrual Cycle Egg matures in the ovary Ovulation: egg is released into the fallopian tubes Lining of the uterus thickens (preparing for a fetus) If unfertilized, lining and egg break down Flows out of the body through the vagina(mestruation) Cycle last about 28 days

10. Fertilization Occurs in upper 1/3 of Fallopian tube Once one sperm enters, egg membrane changes Fertilized egg = zygote Single celled Zygote starts cell division to become many celled Embryo

11. Implantation Embryo is implanted into thick walls of uterus Membranes form the amniotic sac- filled with fluid to protect the embryo Tissues from the embryo and uterine wall form the placenta: where food and oxygen are transferred from mother to baby Embryo is connected to the placenta by an umbilical cord

12. STAGES OF DEVELOPMENT

13. 1 st Trimester Heart develops first Neural tube develops All body systems appear by Week 8 – Now a Fetus

14. 2 nd Trimester Mostly growth Looks more like a baby Some preemies survive at this stage

15. 3 rd Trimester More growth Kicking, rolling, stretching Eyes open – Week 32 Lungs mature Rotates to head-down position

16. Birth Labor –Uterine contractions begin –Cervix dilates to 10 cm. Birth –Uterus pushes baby through vaginal canal Placenta delivered after

17. Infancy From birth – 2 yrs old 1 month: –Suck thumb, reach for objects 3 months –Hold head up 5 months –Grasp objects 7 months –Crawling 10-15 month –walking

18. Childhood From 2 yrs – 13 yrs –Mental abilities increase –Develop language skills –Build muscle

19. Adolescence From 13 yrs – 19 yrs –Start of puberty –Growth spurts –Build muscle

20. Adulthood From 20 yrs – ? –All body system are fully matured –After 30 yrs aging begins