The document summarizes the male and female reproductive systems in humans. It discusses the key parts of each system including how sperm and eggs are produced. It also describes fertilization, prenatal development through each stage of pregnancy, and birth. The roles of hormones like estrogen and testosterone are explained. Factors that can impact prenatal development like nutrition, drugs, and infections are also covered at a high level.

1. Name: ______________________ Reproduction and Humans
I. Male Reproductive System
a. It forms two main functions
i. Produces sperm
ii. Deposits sperm into the female reproductive tract
b. How does it work?
i. The testes (male gonad that produces sperm &
testosterone) produces the sperm
ii. The testes are found in the scrotum
1. What is the Scrotum?
a. Scrotum is a sac of skin, below male
genital organs and contains two testes.
b. It is also 1-2 degrees Celsius cooler in
there than the rest of the body
i. This provides the correct temp for
sperm production and storage.
iii. From the testes the sperm moves through the sperm
duct and the urethra
1. Urethra is the tube inside the penis
a. The penis is a structural adaptation for
internal fertilization
c. What is Semen?
i. Glands secret (let out) a liquid into the tubes.
ii. The liquid is used as a transport agent for the sperm
iii. The liquid and sperm cells make up SEMEN.
d. What is Testosterone?
i. Not only do the testes produce sperm, but it also
produces a hormone called Testosterone.
1. This regulates the maturity of the sperm
2. Also it causes a lower voice pitch
3. And beard development
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2. Name: ______________________ Reproduction and Humans
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3. Name: ______________________ Reproduction and Humans
II. The Female Reproduction System
a. What are the parts of the female reproductive system?
i. Ovaries
1. The ovaries are paired structures located in the
lower portion of the female body cavity.
2. Ovaries produce eggs (ova) in tiny cavities called
follicles
ii. Oviduct
1. After ovulation ( release of the egg from the
ovary) the egg is brought to the uterus (muscle
organ in female where the fetus develops)
through the oviduct (fallopian tube)
iii. Cervix
1. At the lower end of the uterus, known as the
cervix, there is a muscular tube, called the
vagina.
iv. Vagina
1. The vagina receives the sperm from the male and
the birth canal.
b. Where do the eggs come from?
i. When a female baby is born she has all her eggs that
she will ovulate in an immature form.
ii. Usually only one egg is released in her body at a time
c. What else do the ovaries do?
i. In addition to eggs the ovaries also produce the female
sex hormones
1. estrogen
2. progesterone.
ii. These hormones are in charge of
1. secondary female sex characteristics
a. Mammary glands – breasts
b. Wider pelvis
c. Menstrual cycle
d. What is the Menstrual cycle ?
i. The menstrual cycle begins when a girl hits puberty
and continues until she hits menopause.
1. Puberty – time in a person’s life where they begin
to produce gametes and sex hormones
2. Menopause – a time in a woman's wife when she
stops menstruating
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4. Name: ______________________ Reproduction and Humans
ii. On average the cycle is 28 days long (every woman is
different)
iii. There are 4 stages to the cycle
1. Stage #1 follicle stage
a. Involves the maturing of an egg in a follicle
b. It also secrets the hormone estrogen
c. Estrogen starts the thickening of the blood
tissue in the uterus
2. Stage #2 Ovulation
a. When the follicle releases the egg
3. Stage #3 Corpus Lustrum stage
a. After the release of the egg Corpus
Lustrum comes out of the follicle
b. This is a yellow group of cells that lets out
progesterone which enhances the uterine
lining.
4. Stage #4 Menstruation
a. So now the egg is in the Uterus ready to be
fertilized
b. If the egg is not fertilized it goes through a
periodic shedding of the thickened Uterine
lining
i. Usually lasts a few days
iv. Role of Hormones in Menstrual cycle
1. The reproductive cycle of human female involves
interactions in hormones from hypothalamus,
ovaries and pituitary glands
a. FSH – follicle stimulus hormone-
i. Released during menstrual cycle
from the pituitary glands
ii. Stimulates follicle growth and
ovaries to produce estrogen
b. LH- Luteinizing Hormone
i. Also during cycle and from the
pituitary gland
ii. Influences the functioning of the
ovaries
iii. Stimulates growth of the Corpus
lotem to secrete Progesterone which
helps estrogen production
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5. Name: ______________________ Reproduction and Humans
2. Homeostasis with the Hormones
a. The ovaries secrete estrogen and
progesterone to start the changes in the
uterus
b. Estrogen stops the release of FSH make
sure not too much
III. Fertilization & Development
a. We all know the basics of how humans fertilize
b. Fertilization usually occurs in the upper 1/3 of the oviduct
i. Oviduct – same as fallopian tube – transports egg from
follicles to ovary
ii. If eggs not fertilized within 24-48 hours after ovulation
the eggs starts to go bad.
iii. If fertilization does occur the for 6-10 days cleavage
occurs in the oviduct and then the zygote goes and
implants itself in the uterus lining
iv. At this stage the yolk has been depleted but the embryo
gets it’s nourishment from the uterus.
IV. Twins
a. If more than one egg is released and fertilized multiple births
can occur
Identical Twins Fraternal Twins
When the zygote splits during the When the fallopian tubes release
cleavage stage two eggs and they both get
The children will look alike fertilized by sperm
V. Medical abilities to help parents have children
a. In vertro fertilization (IVF) - is when doctors take out the
egg and the sperm and put them together in a test tube and
then implants the zygote into the uterus of the woman
b. Done when woman have trouble conceiving
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6. Name: ______________________ Reproduction and Humans
VI. Prenatal Development (STEP BY STEP AND DIFFERENT
PARTS)
1. Fertilization 2. Cleavage
When the sperm meets the egg a. the multiplying of cells
b. done in the oviduct
3. gastrulating 4. Differentiation and Growth
a. done after the embryo is •Results in the formation of
implanted in uterus specialized tissue and organs from
the different layers of the gastrula
a. Prenatal development is dependent on structures similar to
those in external developing eggs
i. Placenta
ii. Amnion
iii. Umbilical cord
Placenta Umbilical Cord
a. “connection” between mother a. AKA “life line”
and baby b. Holds the blood vessel
b. Allows nutrients, respiratory
gases, and wastes to be
that carry material from
exchanged between embryo and mom to embryo
mom
c. There is no direct connection
•Therefore the blood of the mother and
embryo do not mix
Amnion
a. Is the membrane that
surrounds the embryo
b. It contains the ammonic
fluid that protects the
embryo from shock and
temperature changes
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7. Name: ______________________ Reproduction and Humans
VII. Nutrition and Pregnancy
a. It is important for prenatal development that there is a
balance of nutrients going to the embryo
b. Good nutrition during pregnancy is good for mom and embryo
development
VIII. Avoid Health Issues
a. In Humans Embryonic development of essential organs occur
early on
b. The embryo may encounter risks from problems with genes
and it’s mother exposure to hazards in the environment
i. Drugs
ii. Toxin
iii. Alcohol
iv. Smoke
v. Infections
IX. Birth
a. Usually in humans occurs after 9 months
b. During birth strong contractions of the uterine muscles (labor)
will force the baby through the cervix and the vagina ( birth
canal)
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8. Name: ______________________ Reproduction and Humans
c. The getting rid of the placenta occurs after birth
d. If placenta stays in will probably cause infection
X. Postnatal development
a. Continues with different parts of the body growing at different
rates
b. This process goes all the way through until a person dies
does not stop at adults
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