Human Reproductive System
Male Reproductive System
Sperm Formation
• • • • • MEIOSIS Form in testes Temperature important! Scrotum Leave testes via epididymus to the vas deferens
Semen
• Fluids help to transport, feed, and protect sperm • Seminal vesicles • Prostate gland • Bulbourethral glands
Secondary Sexual Characteristics - Male
• Produced by testosterone – Deeper voice – Axillary and pubic hair – Chest and facial hair – Lengthen bones – Increased size of testes for sperm production
Female Reproductive System
Ovum Formation
• MEIOSIS • Ova are formed before birth • 1 ovum per month is matured and released from ovaries
Secondary Sexual Characteristics - Female
• Induced by increased LH, FSH, estrogen, and progesterone hormone levels – Axillary and pubic hair – Widen pelvis – Enlarge mammary tissue – Begin menstrual cycles
Fertilization
• Occurs in upper 1/3 of Fallopian tube • Once one sperm enters, egg membrane changes • Fertilized egg = zygote
Implantation
• Implanted into thick walls of uterus • Chorion membranes dig into uterus to form placenta • Embryo supported via umbilical cord • Once pregnant, progesterone levels stay high in mom
st 1
Trimester
• Heart develops first • Neural tube develops • All body systems appear by Week 8 – Now a Fetus
nd 2
Trimester
• Mostly growth • Looks more like a baby • Some preemies survive at this stage
rd 3
Trimester
• • • • •
More growth Kicking, rolling, stretching Eyes open – Week 32 Lungs mature Rotates to head-down position
Birth
• Labor – Uterine contractions begin – Cervix dilates to 10 cm. • Birth – Uterus pushes baby through vaginal canal • Placenta delivered after
Most of this not fun?