Developmental Psych: Ch 3

fetal alcohol spectrum disorders

a cluster of abnormalities and problems that appears in the offspring of mothers who drink heavily during pregnancy

teratogen

any agent that can potentially cause a physical birth defent

placenta

consists of a disk-shaped group of tissues in which small blood vessels from the mother and the offspring intertwine but don't join

umbilical cord

contains two arteries and one vein, and connects the baby to the placenta

psychoactive drugs

drugs that act on the nervous system to alter states of consciousness, modify perceptions, and change moods

teratology

field of study that investigates the causes of birth defects

neurogenesis

formation of new neurons

viable

has a chance of surviving outside the womb

germinal period

includes the creation of the zygote, continued cell division, and the attachment of the zygote to the uterine wall

endoderm

inner layer of cells, which develops into digestive and respiratory systems

3 in/3 oz

length of fetus/weight of fetus at 3 months

6 in/4-7 oz

length of fetus/weight of fetus at 4 months

12 in/1 lb

length of fetus/weight of fetus at 5 months

14 in/1-1.5 lb

length of fetus/weight of fetus at 6 months

amnion

life-support system that is a thin bag or envelope that contains a clear fluid in which the developing embryo floats

neurons

nerve cells, which handle information processing at the cellular level

neuronal migration

occurs at approximately 6 to 24 weeks after conception; involves cells moving outward from their point of origin to their appropriate locations and creating the different levels, structures, and regions of the brain

ectoderm

outermost layer of cells, which becomes the nervous system and brain, sensory receptors (ears, nose, and eyes) and skin parts (hair and nails)

germinal period

period of prenatal development that takes place in the first two weeks after conception

organogenesis

process of organ formation that takes place during the first two months of prenatal development

implantation

takes place about 10 to 14 days after conception

embryonic period

takes place about two to eight weeks after conception

implantation

the attachment of the zygote to the uterine wall

blastocyst

the inner mass of cells that develops during the germinal period; these cells later develop into the embryo

mesoderm

the middle layer of cells, which becomes the circulatory system, bones, muscles, excretory system, and reproductive system

trophoblast

the outer later of cells that develops in the germinal period; these cells alter provide nutrition and support for the embryo

embryonic period

the period of prenatal development that occurs two to eight weeks after conception; the rate of cell differentiation intensifies, support systems for the cells form, and organs appear

fetal period

the prenatal period of development that begins two months after conception and lasts for seven months on average