7th Period Notes
Amniotic Sac: a thin, fluid-filled membrane that surrounds and protects the developing embryo.
Umbilical Cord: a ropelike structure that connects the fetus with the mother’s placenta.
Placenta: a thick, blood rich tissue that lines the walls of the uterus during pregnancy and nourishes the
embryo.
Twins and other multiple births result when multiple embryos are formed
Identical Twins
Fraternal Twins
+Single zygote splits into 2
+2 eggs are released and are fertilized by 2 different
separate embryos
sperm
+Identical traits and same gender
+Can have different traits and different genders
Healthy Pregnancy
-A woman needs prenatal care during pregnancy. There are steps that a pregnant female can take to
provide for her and the baby’s health.
-Eating Needs:
Nutrient
Calcium
Protein
Iron
Vitamin A
Vitamin B Complex
Folic Acid
Purpose
Bone, teeth, nerve, muscle and heart growth
Muscle and other tissue health
Red blood cell development, supplies oxygen to cells
Growth of cells and bones, eye development
Aids in forming nervous system
Critical in development of Central Nervous System
-Physical activity can help a pregnant a pregnant female, but you need to discuss physical activity with
your health care provider before beginning.
-Tobacco Use:
+Exposure to secondhand smoke increases the risk of low-birth-weight babies
+May affect growth, mental development and behavior after the child is born
-Fetal Alcohol Syndrome
+Alcohol-related birth defects that includes both physical and mental problems
+Can cause learning, memory, and other problems as well as visual and hearing impairments
-Avoid Hazards in the environment, a pregnant female should do all she can to avoid common hazardous
substances including: Lead, Mercury, Smog, and Radiation
Complications of Pregnancies
Complication
Cesarean Delivery
Premature Birth
Miscarriage
Gestational Hypertension
Ectopic Pregnancy
Symptoms/Definition
Made through an incision in the mother’s abdomen
Birth to the child at least 3 weeks before the due date
Spontaneous expulsion of the fetus before the 20th week of pregnancy
High blood pressure during pregnancy; Preeclampsia is a severe form
When a zygote implants in the fallopian tube, abdomen, ovary or
cervix instead of the uterus
3 Steps of Child Birth
1. Labor
a. Muscle contractions of uterus become regular, stronger, and closer together
b. Cervix widens, or dilates
2. Delivery
a. Once fully dilated, baby passes through birth canal and emerges from mom’s body
3. Afterbirth
a. Contractions continue until the Placenta is pushed out
Genes: sections of chromosomes that occur in pairs
-23 come from the mother, 23 come from the father for a total of 46 pairs of chromosomes
-There are both dominant and recessive genes, if the dominant genes are present, the recessive
genes will not be
The male determines the gender of the baby. Females always contribute the X chromosome to the
embryo, the sperm will either carry an X or Y chromosome. XX = female, XY=male