Chapter 28 Flashcards
pregnancy and development (18 cards)
What is a zygote?
a fertilized egg
After 6-7 days the fertilized egg is now called a ____ and it adheres to the inner layer of the uterus called the ____
blastocyst; endometrium
After implantation the trophoblast releases the hormone ____
hCG
What does the endoderm develop into?
lining of the digestive and respiratory tracts
What does the mesoderm develop into?
muscles, bones, the circulatory system, kidneys, gonads, and the connective tissues throughout the body.
What does the ectoderm develop into?
brain, spinal cord, nervous system and skin epidermis
What does the chorion develop into?
chorionic villi, fetal part of placenta
What is the function of the placenta?
provides nutritive, respiratory, excretory, and endocrine functions.
What is the function of the umbilical cord?
connect fetus to placenta, deliver oxygen and nutrients, remove waste products
What blood vessels are located in the umbilical cord?
2 umbilical arteries and one umbilical vein.
What is the function of the amnion?
protect embryo, maintain temperature, prevents parts from fusing together
By ____ weeks the embryo develops a pumping heart
3 1/2
The fetal stage of development begins at ____ weeks
9, through 38
Name the 3 phases of labor and describe what occurs in each phase
Dilation stage- onset to full dilation of cervix and effacement, longest stage, contractions start as weak and become more rapid, head enters true pelvis
Expulsion stage- full dilation to delivery, strong contractions, crowning, baby pushed out
Placental stage- delivery of afterbirth, detachment of placenta
What hormone stimulates uterine contraction?
prostaglandins and oxytocin
What hormone stimulates lactation?
prolactin
What hormone stimulates milk ejection let down?
oxytocin
What is colostrum?
Yellowish fluid that has less lactose but more protein, vitamin A, and minerals than true milk, as well as almost no fat
Also rich in IgA antibodies
