Download Human Reproduction Wkst

THE DEVELOPING PLACENTA
During the early stages of embryonic development, a thin membrane called the amniotic
sac develops, which surrounds and protects the embryo. The membrane contains amniotic
fluid, which cushions the fetus and helps to maintain even temperature throughout
pregnancy.
The outer cells of the embryo form projections, called “villi” that attach themselves to the
uterine wall. This attachment becomes the placenta, a vascular spongy structure through
which the embryo, and later the developing fetus, derives oxygen, antibodies and nutrients
from the maternal blood supply. Waste products also pass from the fetus back to the
maternal blood supply through the placenta. The embryo is connected to the placenta by
the umbilical cord.
Soon after implantation, the placenta secretes a hormone called HCG (human chorionic
gonadotrophin). HCG prevents the disintegration of the corpus luteum, which will secrete
large quantities of estrogen and progesterone. Increased estrogen production also causes
the enlargement of the uterus, breasts, and external genitalia. Increased progesterone
helps to maintain the endometrium, prevents uterine contractions during the pregnancy,
and prepares the breasts for lactation.
Part 1: Compare and Contrast reproductive cells using information from the pages before
Criteria
SPERM
OVUM/EGG
Size
Shape
Mobility
Location of Nucleus
Chromosome #
Mitochondria Amt.
Food Reserves
Protection
Part 2: Compare and Contrast Overall Reproductive Systems using information from the
text.
Structure or Function
Male Reproductive System
Female Reproductive System
Sex Cell
Where sex cell made?
Tube for sex cell travel
Sex hormone?
Where hormone made?
Sex cell exit? Where?
XXXXXXXXXXXXXXXXXX
Where egg fertilized?
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Fert. Egg grows where?
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Nutrient exchange organ?
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Analysis Questions
1.
In what ways are female and male reproductive systems similar (give 2)? In what
ways are they different (give 2)? (2 pts)
2. Summarize the changes and development an egg goes through from week 1-4:
3. What is differentiation? What week does it begin?
4. What week does the heart begin to beat?_____________
5. When is the nervous system developed enough to begin controlling some
functions?_______
6. Describe the function of the following structures in the development of the fetus:
A. Amniotic Sac:
B. Placenta:
C. Umbilical Cord:
7. Imagine you are a doctor and one of your patients just found out she is pregnant.
Knowing that anything she takes into her body can cross the placenta and affect
the developing fetus, what will you recommend to her in order to have a healthy
baby ( list 4 items)
1)
2)
3)
4)