Child Development: Chapters 4+5

Prenatal development:

the changes that transform the
fertilized egg into a newborn
human.

Zygote:

a fertilized egg.

Implantation:

the burrowing of the zygote
into the uterine wall.

Germ disc:

a small cluster of cells near the
zygote's center that develops
into the baby.

Placenta:

a uterine structure for
exchanging
nutrients and
wastes between mother and
baby.

Embryo:

an embedded zygote.

Mesoderm:

the middle layer of the embryo,
which becomes the muscles,
bones, and circulatory system.

Endoderm:

the inner layer of the embryo,
which becomes the digestive
system and lungs.

Amnion, or amniotic sac:

the sac in which the baby
develops.

Amniotic fluid:

he liquid that fills the amnion
and cushions the baby.

Umbilical cord:

a cord-like structure
containing blood
vessels that
joins the developing baby
through the baby's abdomen to
the mother's placenta.

Cephalocaudal:

growth from the top and
extending
downward.

Proximodistal:

growth from the center and
extending outward.

Fetus:

after the eighth week of
gestation
until birth, the
developing
baby is called a
fetus.

Cerebral cortex:

the folded surface of the brain
that regulates many human
behaviours.

vernix

a thick, greasy coating on the
skin that protects the baby
during gestation.

Age of viability:

the age at which most bodily
systems function well enough
to support life once the baby
is born.

Embryo

3-8 weeks, Period of rapid growth, most body structures
begin to form

Spina bifida:

a disorder in which an
embryo's
neural tube does
not close properly during
development.

Teratogen:

any agent that disrupts normal
prenatal development.

AIDS

Frequent infections, neurological disorders, death

Cytomegalovirus

Deafness, blindness, abnormally small head, cognitive delay

Genital herpes

Encephalitis, enlarged spleen, improper blood clotting

Rubella (German measles)

Cognitive delay; damage to eyes, ears, and heart

Syphilis

Damage to the central nervous system, teeth, and bones

Fetal alcohol spectrum
disorder (FASD):

a developmental disorder
caused by maternal
consumption
of alcohol during
pregnancy.

alcohol consequences

Fetal alcohol spectrum disorder, cognitive deficits, heart damage, retarded
growth

aspirin consequences

Deficits in intelligence, attention, and motor skill

caffeine consequences

Lower birth weight, decreased muscle tone

cocaine and heroin consequences

Retarded growth, irritability in newborns

marijuana consequences

Lower birth weight, less motor control

nicotine consequences

Retarded growth, possible cognitive impairments

solvents consequences

Cognitive delays, neuromotor functioning deficits

hazard of lead

cognitive delay

hazard of mercury

Retarded growth, cognitive delay, cerebral palsy

hazard of PCB's

Impaired memory and verbal skills

hazard of X-rays

Retarded growth, leukemia, cognitive delay

Ultrasound:

a medical procedure that
involves
imaging a developing
baby using sound waves.

Amniocentesis:

a medical procedure in which
a sample of amniotic fluid is
taken and tested for genetic
disorders.

Chorionic villus sampling
(CVS):

a medical procedure in which
a sample of placental cells is
taken and tested for genetic
disorders.

Maternal-fetal medicine:

a medical practice specialty
focusing
on high-risk
pregnancy and on treating
fetal health problems in utero.

Cervix:

the opening at the end of the
uterus (top of the vagina) that
forms the entryway to the
birth canal.

Crowning:

the appearance of the top of
the baby's head outside the
birth canal.

Breech presentation:

a physical position in utero in
which the developing baby's
feet, rather than the head, are
closest to the birth canal.

stage 1 of labour

12-24 hours, cervix enlarges to 10 cm

stage 2 of labour

1 hours, baby moves down the birth canal

stage 3 of labour

10-15 minutes, placenta is expelled

Doula:

a nonmedically trained person
who provides coaching, personal
support, and education
about birth but does not provide
medical care or intervention
during the birth process.

Obstetrician:

a physician who specializes
in women's health and
reproduction.

Caesarean section
(C-section):

delivery of a baby through a
surgical incision in the mother's
abdomen.

Midwife:

a person who is not a physician
but who is trained to
assist mothers in the physical
delivery of their babies by
normal, spontaneous vaginal
delivery.

Anoxia:

complete oxygen deprivation
(lack of oxygen).

Placental abruption:

detachment of the placenta
from the uterine wall.

Hypoxia:

a reduced supply of oxygen.

Prematurity:

when a baby is born less than
38 weeks after conception.

Small-for-date infants:

babies who are substantially
smaller at birth than expected
based on the length of time
since conception.

Infant mortality:

the number of infants out of
1000 births who die before
their first birthday.

Apgar score:

a numerical scale used to rate
a newborn baby's vital signs.

Five signs evaluated in the apgar score:

activity, pulse, grimace (response to irritating stimulus), appearance (skin colour), respiration

4 Newborn States

Alert inactivity (calm, inspecting), waking activity (unfocused, unorganized motion), Crying, Sleeping

Rapid-eye-movement (REM)
sleep:

a period during sleep involving
small physical movements or
twitches of the eyes, mouth,
arms, and legs (irregular sleep).

Non-REM sleep:

a period during sleep that is
motorically quiet and involves
steady breathing, heart rate,
and brain activity.

Sudden infant death
syndrome
(SIDS):

a syndrome in which a healthy
baby dies suddenly, usually
during sleep, for no apparent
reason (crib death).

Postpartum depression:

feelings of low self-worth,
disturbed sleep, poor appetite,
and apathy in the months after
delivering a baby.

Epiphyses:

the ends of the cartilage structures
that turn into bone.

Secular growth trends:

changes in physical
development from one generation
to the next that are related
to environmental
factors.

Hormones:

chemicals that are released
by glands and travel in the
bloodstream
to act on other
areas of the body.

Thyroxine:

a hormone released by the thyroid
gland that is essential for
nerve-cell development.

Rice cereal, then other cereals, strained vegetables, then strained fruits can be introduced at

6-9 months

Protein foods (cheese, yogurt, cooked beans, pureed meats) can be introduced at

7-9 months

Finely chopped meat, toast, crackers can be introduced at

9-10 months

Egg yolk can be introduced at

10-12 months

Malnutrition:

a lack of adequate nutrition
indicated, in part, by children
being small for their age.

Neuron:

a cell in the nervous system
that specializes in transmitting
information.

Neuronal cell body:

a structure at the center of the
neuron containing biological
mechanisms for maintaining
cellular life.

Dendrites:

branch-like extensions
off the neuron that allow for
intercellular communication.

Axon:

the tube-shaped structure
attached to the cell body that
transmits electrical messages
received through the dendrites
to other neurons.

Myelin:

a fatty sheath that insulates
the axon and speeds
information transfer.

Terminal buttons:

structures at the ends
of an axon that release
neurotransmitters.

Neurotransmitters:

chemicals that affect the firing
of surrounding neurons.

Synapse:

a gap or space between
neurons.

Cerebral hemispheres:

the right and left halves of the
cerebral cortex.

Corpus callosum:

a thick bundle of axons that
joins the left and right hemispheres
of the cerebral cortex.

Frontal cortex:

an area at the front of the brain
that is responsible for planful
activities and personality.

Neural plate:

a group of cells forming about
three weeks after conception
that develops into the neural
tube, the brain, and the spinal
cord.

Synaptic pruning:

synapses begin to disappear as
the brain weeds out unnecessary
or underutilized connections
between neurons.

Electroencephalogram
(EEG):

an electrical measurement of
brain waves.

Functional magnetic
resonance
imaging (fMRI):

a medical test that measures
the flow of blood in the brain
using magnetic fields.

Positron emission
tomography
(PET scan):

a medical test that traces
glucose
uptake in the brain.

Functional near infrared
spectroscopy (fNIRS):

a neuroimaging technique that
measures blood flow in the
brain and is less invasive than
fMRI and easier to use with
infants.

Neuroplasticity:

the extent to which brain
organization is flexible.

Motor skills:

coordinated movements of the
muscles and limbs.

Locomotion:

moving about in the world.

Fine-motor skills:

activities, such as grasping,
holding, and manipulating
objects, that involve smallmuscle
groups.

Gross-motor skills:

activities, such as running,
throwing, and jumping,
requiring large-muscle groups.

Reflexes:

unlearned responses that are
triggered by a specific form of
stimulation.

Dynamic systems theory:

a theory that upholds that
motor
development involves
many distinct skills, organized
and reorganized over time to
meet demands of specific tasks.

Differentiation:

mastery of component skills.

Integration:

combining component skills in
proper sequence into a coherent,
working whole.

Auditory threshold:

the quietest sound that a person
can hear.