Child Dev. Ch. 3

Trophoblast

(1 week after conception) an outer layer of cells that later provides nutrition and support for the embryo.

Blastocyst

(1 week after conception) the inner mass of cells that develops during the germinal period. these cells later develop into the embryo

Neural Migration

(6 to 24 weeks after conception). Cells moving outward from their point of origin to their appropriate locations and creating different levels, structures, and regions of the brain. Once cell has migrated must mature and develop to a more complex structure.

Fetal Period

(lasts about 7 months) the prenatal period between two months after conception and birth in typical pregnancies.

Spina Bifida

(neural tube defect) an incomplete development of the spinal cord results in varying degrees of paralysis of the lower limbs. usually need assistive devices--crutches, braces, wheelchairs.

Anencephaly

(neural tube defect) occurs when the head of the neural tube fails to close, the highest regions of the brain fail to develop and the fetus dies in the womb, during child birth, or shortly after birth.

4 Important Phases of Brain Development

1. the neural tube 2. neurogenesis 3. neural migration 4. neural connectivity

Fetus at 5 months

12 in, close to 1 lb. Structures of the skin have formed--toenails and fingernails. more active. shows preference for a particular position in the womb.

Fetus at 6 months

14 in, 1/2 to 1 lb. eyes and eyelids completely formed and fine layer of hair covers the head. Grasping reflex is present and irregular breathing movements occur.

Maternal Weight Gain

25 to 35 lbs associated with best reproductive outcomes. Obese women should limit gestational weight gain to 11 to 20 lbs.

Down Syndrome risk

40 yrs.: 1 in 100 50 yrs: 1 in 10

Prevent Neural Tube Defects

B vitamin folic acid. avoid diabetes, obesity, stress, and secondhand tobacco smoke.

3 Trimesters of Prenatal Growth

First Trimester: first 3 months Second Trimester: middle 3 months Last Trimester: last 3 months"

Incompatible blood Types

If fetus is Rh positive and mother is Rh negative the mother's immune system may produce antibodies that will attack the fetus. Generally the first Rh positive baby will not be at risk but with each pregnancy risk increases. (stillbirth, anemia, jaundice, heart defects, brain damage, or death soon after birth).

Neurogenesis

Occurs after neural tube has closed. 5th prenatal week. formation of new neurons.

Nicotine

Preterm births, low birth weights, fetal & neonatal deaths, and respiratory problems, Sudden Infant Death. May cause ADHD. asthma and wheezing in adolescence.

Teratogen

any agent that can potentially cause a physical birth defect. Influenced by: Time of Exposure Dose Genetic Suspectibility

Lead

can affect child's mental development.

Radiation

can cause gene mutation. chromosomal abnormalities. X-rays have radiation. Can cause microencephaly--an abnormally small brain, leukemia, and intellectual disabilities.

Alcohol Spectrum Disorder

cluster of abnormalities and problems that appears in the offspring of mothers who drink heavily during pregnancy. (neurocognitive difficulties, facial deformities, learning problems, and intellectual disability or below average intelligence).

At 23 weeks

connections between neurons occur which continues postnatally.

Placenta

consists of a disk-shaped group of tissues in which small blood vessels from the mother and the offspring intertwine but do not join.

Umbilical Cord

contains two arteries and one vein that connect the baby to the placenta

Marijauna

deficits in memory and information processing. learning and memory difficulties at age 11. low intelligence. depressive symptoms at 10. stillbirth.

Caffeine

does not increase risk of miscarriage. lowers birth weight and may cause baby being born small for gestational age.

Rate of still birth

elevated for mothers who are adolescences or 35 yrs an older

Last 2 months of Pregnancy

fatty tissues develop and the functioning of various organs

Neural Tube

forms about 18 to 24 days after conception. develops out of the ectoderm. Tube closes at the top and bottom 24 days after conception.

Methamphetamine

high infant mortality rate, low birth rate, and developmental and behavioral problems. decreased arousal, increased stress, and poor movement quality in newborns. less brain activation especially in frontal lobes in 7 to 15 year olds. ADHD in 5 yrs. smaller head circumference.

Embryo's Endoderm

inner layer of cells which will develop into the digestive and respiratory system. primarily produces internal body parts.

Amnion

like a bag or envelope and contains a clear fluid in which the developing embryo floats. provides an environment that is temperature and humidity controlled as well as shock proof.

Tobacco smoke or secondhand smoke

low birth weight and diminishing ovarian functioning in female offspring.

Cocaine

low birth weight, length and head circumference. lower arousal, less effective self-recognition, higher excitability, and lower quality of reflexes at 1 month old. impaired motor development in 2nd year of life. slower growth rate through 10 yrs of age. elevated blood pressure at 9 yrs. impaired language development and information processing. learning disability at age 7. attention deficits. special ed.

Neurons

nerve cells. handle information processing at the cellular level of the brain

Organogenesis

process of organ formation during the first 2 months of prenatal development.

Implantation

the attachment of the zygote to the uterine wall takes place about 10 to 14 days after conception.

Fetus at 3 months

the fetus is 3 inches long weighs 3 oz, It has become active arms and legs move mouth opens and closes head moves. The face, forehead, eyelids, nose, and chin are distinguishable as are the upper arms lower arms, hands, and lower limbs. Genitals can be identified.

Fetus at 4 months

the feus has grown to 6 in. long, 4-7 oz. growth spurt occurs in the body's lower parts. mother can feel the arm and leg movements.

Embryo's Mesoderm

the middle layer which will become the circulatory system, bones, muscle, excretory system, and reproductive system. primarily produces parts that surround internal areas.

Embryo's Ectoderm

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

Embryonic Period

the period of prenatal development that occurs for 2 to 8 weeks after conception. The rate of cell differentiation intensifies, support systems for the cells form, and organs appear.

Germinal Period

the period of prenatal development that takes place in the first two weeks after conception. Includes creation of the zygote, continued cell division, and the attachment of the zygote to the uterine wall

Heroin

withdrawal symptoms--irritability, tremors, abnormal crying, disturbed sleep, and impaired motor control. attention deficits. behavioral problems--1 yr.