Chapter 3 - Prenatal Development, Birth, and the Newborn Flashcards
(95 cards)
What are the weeks for the period of the zygote?
Weeks 1-2
What are the weeks for the period of the embryo?
Weeks 3-8
What are the weeks for the period of the fetus?
Weeks 9-38
The period of the zygote begins when:
the egg is fertilized in the fallopian tube
After about 4 days, the zygote is called a ________; a hollow ball of about 100 cells
blastocyst
The period of the zygote ends 2 weeks later when the Zygote is:
implanted in the wall of the uterus
The _________ is formed between mother and developing organism to provide nutrients and remove waste
placenta
What is an ectopic pregnancy?
The zygote gets stuck in the fallopian tube
Body structures and internal organs are formed during the period of the _______
embryo
True or False: Blood circulation systems do not develop until the period of the fetus
False: they develop in the period of the embryo
What are the three levels of the embryo?
Ectoderm, Mesoderm, Endoderm
What is the ectoderm?
The outer part of the embryo, that develops into the internal organs
What is the mesoderm?
The inner layer of skin that forms into muscles and the skeleton
What is the endoderm?
The nervous system - the inner part of the embryo - the brain, spinal cord, hair, nails, teeth, etc.
The amniotic sac is filled with ____________.
amniotic fluid
The job of the amniotic sac is to:
keep the embryo safe
The _________ joins the embryo to the placenta
umbilical cord
The uterus is ______ and composed of ________
round; many layers
The uterine wall is a:
thick muscle and the outer layer of the uterus
What are villi?
Blood vessels that come together to form the umbilical cord
In the period of the fetus, all regions of the _____ grow.
brain
Genital organs and extremeties develop in the ______ month, (week __)
third; 12
The skin is covered with a thick, greasy substance, called
vernix
By ___ months, the fetus can hear sound
six