Human Reproductive
System Review
Mrs. Degl
Male Reproductive
System
Mrs. Degl
Sperm Formation
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MEIOSIS forms sperm in gametes
Sperm forms in testes
Scrotum keeps cooler than rest
Semen is sperm plus protecting fluid
Semen leaves testes through the vas
deferens (sperm ducts) to the
urethra before it exits.
Mrs. Degl
Secondary Sexual
Characteristics - Male
• Produced by testosterone
– Deeper voice
– Chest and facial hair
– Lengthen bones
– Increased size of testes for
sperm production
Mrs. Degl
Female Reproductive
System
Mrs. Degl
Ovum Formation
• MEIOSIS forms the eggs (ova)
• Eggs are formed before birth
• 1 egg per month is matured and
released from ovaries, most of
the time
• Eggs travel through the fallopian
tube where they may become
fertilized
Mrs. Degl
Secondary Sexual
Characteristics - Female
• Induced by increased LH, FSH,
estrogen, and progesterone
hormone levels
– Pubic hair
– Widen pelvis
– Enlarge mammary tissue
(breasts)
– Begin menstrual cycles
Mrs. Degl
Fertilization
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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
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
1st Trimester =
1st 12 weeks
• Heart develops first
• Neural tube develops
• All body systems appear by
Week 8 – Now a Fetus
Mrs. Degl
2nd Trimester =
up to 24 weeks
• Most growth
• Looks more like a baby
• Some preemies survive at this
stage
Mrs. Degl
3rd Trimester
= Up to 40 weeks
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More growth
Kicking, rolling, stretching
Eyes open – Week 32
Lungs mature
Rotates to head-down
position, unless baby is
breech
Mrs. Degl
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 vaginally
Mrs. Degl