Child development ch.3

Germinal period

Period that begins at conception and lasts until the developing organism becomes attached to the uterus about 8- 10 days later

Embryonic period

period that extends from the time the organism becomes attached to the uterus until the end of the 8th week of pregnancy, when all the major organs have taken primitive shape

Fetal period

A period that begins in the 9th week after conception with first signs of hardening the bones and continues till birth

Why is the germinal period so crucial

- it moves slowly through fallopian tube and if zygote enters uterus too fast or slow, uterine environment will not be hormonally prepared and organism destroyed

Mitosis

where all body cells reproduce through duplication and cell division

Cleavage (1st step)

Series of mitotic cell divisions that transform a zygote into a blastocyst

heterochrony

Variability in the rates of development of different parts of an organism

Heterogeneity

Variability in the levels of development of different parts of an organism at a given time

Totipotent stem cells

Cells that have potential to grow into complete embryo and become a normal healthy infant.

- Twins come from same stem cell and divide into two cell masses

Stem cells

- harbored into various tissues and organs they are a part of

Research on stem cells

Many scientists believe that they have the potential to be used to therapeutically replace damaged cells with diseases like heart disease, leukemia, Parkinson's, and diabetes

Implantation

The process where the developing organism attaches to the uterus with mothers blood vessels

Important part about implantation

It marks the transition between germinal and embryonic period

- can still be a dangerous stage and termination of pregnancy is common

How long does the embryonic period last for if successful

6 weeks

Amnoin

Thin, tough, transparent membrane that holds the amniotic fluid which surrounds the embryo

What does the amniotic fluid do

cushions organism as the mother moves and gives liquid support for weak muscles, soft bones, and give medium where it can move and change position

Chorion

membrane that surrounds the amnion and become the fetal component of the placenta

Placenta

Organ made up of tissue from both mother and fetus that serves as a barrier and filter between their bloodstream

Umbilical cord

flexible helical structure containing blood vessels that connects the developing organism to the placenta

- 20 inches long and filled with Wharton's jelly that help with flexibility

Ectoderm

Cells of inner cell mass of the embryo that develop into outer surface of skin, nails, part of teeth, lens of eye, iner ear, and central nervous system

Endoderm

Cells of the inner cell mass of the embryo that develop into the digestive system and the lungs

mesoderm

Cels of inner mass of the embryo that give rise to the muscles, bones, circulatory system, and inner layers of skin

Epigenesis

Process where a new phenotypic form emerges through the interactions of the preceding form and its current environment

Cephalocaudal Pattern

The pattern of development that

Gonadal ridges

Both male and females have two ridges of tissue where both male and female sex organs will develop

Androgens

male gonads with higher levels of hormones

- females have lower levels of testosterone

What happens during the fetal period

All basic tissues and organs continue to form and the bones begin to hard or ossify

Age of viability

age at whch the fetus is able to survive on its own

- around the age of 7 months

Touch

early as 8 weeks following conception the fetus begins to respond to tactile contact from itself, the womb and umbilical cord and in case of multiple pregnancy from other fetuses

Sensing motion

Middle ear, controls sense of balance begins to function about 5 months after conception and is fully mature after birth

- can sense mother posture

Seeing

26 weeks a bright light is held on the motehrs abdomen and responds with changes in heart rate and movement

Hearing

Fetus responds to sound from 5-6 months after conception

Around when can a mother feel their fetus moving

around 4 months, in later weeks can make mother uncomfortable

- To feel fetus you need to place hand on belly

Dynamic systems theory

helps explains how complex systems of behavior emerge from interaction of less complex parts

Learning in the womb

In just hours of birth, babies can distinguish between vowels sounds of their native language and with mothers and others.

What happens to babies when mothers experience high levels of stress

they have lower level of weight and have a smaller head circumference

- can score lower test scores on behavior and neurological development and exhibit fussiness and fearfulness

- can be caused by the hormones secreted when anxious or under stress

Gestational stage

amount of time between conception and age. between 37 and 43 weeks

Teratogens

environmental agents such as toxins, disease, drugs, and alcohol that increase the risk of deviations in normal development and can lead to serious abnormalities and death

When is it the gravest exposure period for the fetus with teratogens

two weeks of conception

Can certain prescriptions of drugs cause abnormalities to the babies when born?

YES

- they can be born without limbs

- drugs can be accutane, thorazine, and valium

What harm can tobacco do

- can cause spontaneous abortions, stillbirth, and neonatal death

- can cause birth defects of abnormal formation of arms, legs, fingers, and toes

Harmful effects of nicotine

can cause abnormal growth of the placenta and reduction in transfer of nutrients to fetus

- reduces oxygen and increases carbon monoxide in bloodstream of mother and fetus

- birth weights are lower in fetus with tobacco or nicotine

harmful effects of alcohol

- babies suffer from fetal alcohol syndrome spectrum disorder (FASD)

- abnormal appearance, low intelligence, and problems with hearing and vision

What if the most severe form of FAS

- abnormal small head and underdeveloped brain, eye abnormalities, congenital heart disease, joint abnormalities, and malformations of the face

Harmful effects of Marijuana

- can cause effects to the placenta which causes it to grow and cause neurological deficits

harmful effects of cocaine

- seizures, premature rupture amnion, and separation of placenta from uterus for mother

- babies: stillbirth, premature birth, low birth rate, strokes, and birth defects

harmful effects of meth

- the baby was much smaller compared to babies with nonuser mother

Harmful effects of heroin and methadone

they are born addicted themselves and must be given heroin or methadone to prevent life-threatening withdrawal

- can be premature, underweight, and vulnerable respiratory illness

Effects of HIV

Most children living with HIV are passed down by their mothers who are also diagnosed with HIV

- Virus can lead to aids

- Children with HIV are at significant risk of dying first few years with respiratory infections and excessive diarrhea

Rh incompatibility

- complex substance of surface of red blood cells

- composed by a dominant gene

- When Rh negative woman conceives child with Rh positive man child most likely become Rh positive

Apgar scale

You have to weight the baby the first minute and then the next five minutes

- heart beat, respiratory effort, muscle tone, reflex responsively, color

Brazelton Neonatal Assessment Scale

a scale used to assess a newborn's neurological condition

- Orientation to objects

- Pull to sit

- Cuddliness

- Defensive movements

- Self-quieting activity