Chapter 2 review
What is the risk of low birth weight?
- low oxygen levels at birth - trouble staying warm - trouble feeding and gaining weight - infection - breathing problems and immature lungs (infant respiratory distress syndrome) - nervous system problems, such as bleeding inside the brain (intraventricular hemorrhage)
Period of the Fetus (Weeks 9-40)
Develops hair, nails, teeth, and digestive system Sex organs being to differentiate Can respond to sounds Fetus is preparing for birth
Period of the embryo (weeks 3-8)
During this period, body structures and internal organs develop rapidly. at 3 weeks the embryo looks like a salamander but at 8 weeks the embryo looks human.
What makes a baby considered premature or pre-term?
a birth that takes place more than three weeks before the baby's estimated due date. Often have medial problems
Embryo definition
a multi-celled organism between two and eight weeks after fertilization
Zygote definition
a one-cell structure that is created when a sperm and egg fuse
Placenta definition
a structure connected to the uterus that provides nourishment and oxygen from the mother to the developing embryo via the umbilical cord
Fetus definition
a unborn human baby from nine weeks after conception until birth
Common teratogens
alcohol, drugs, nicotine, aminopterin, busulfan, phenytoin
Hypoxia definition
an absence of oxygen in the tissues to sustain bodily function
Teratogens definition
an agent or factor which causes malformation of an embryo
Consequences of FAS
brain damage and growth problems
What are the three layers of the embryo?
endoderm, mesoderm, ectoderm
Period of the zygote (weeks 1-2)
fertilization begins the period of the zygote, the technical term for the fertilized egg. This period ends when the zygote implants itself in the wall of the uterus. by the end of the 1st week the zygote reaches the uterus and then implantation occurs.
What is FAS? / definition
fetal alcohol syndrome; condition in a child that results from alcohol exposure during pregnancy
What is the second stage of labor?
the baby moves down through the vagina and is born
What is the first stage of labor?
the neck of the cervix open to 10cm dilated
What is the third stage of labor?
the placenta is delivered (afterbirth)