Child Development Ch. 4
As a fertilized egg develops into a cell mass, the cell mass splits in two and each part develops into a separate embryo
Identical twins
An egg from the woman is removed, and fertilized with sperm from the man and then placed in the woman's uterus
In vitro-fertilization
Malformed red blood cells interfere with oxygen supply
Sickle cell anemia
What is the only guaranteed way to avoid pregnancy?
Abstinence
A child who is not biologically the couple's child becomes a part of the family
Adoption
Mother's blood is tested to detect abnormal levels of protein AFB; no known risk
Alpha-fetoprotein (AFB)
A small amount of amniotic fluid is removed and tested; some risk to fetus
Amniocentesis
The liquid that surrounds and protects the developing baby in the uterus
Amniotic fluid
Sperm is injected into a woman's uterus
Artificial insemination
Why is it critical to avoid taking medications in the first three months of pregnancy unless specifically prescribed?
Because the baby's body systems, including the brain, are forming. Chemicals in some medications taken at this time may cause severe harm, including mental retardation.
Summarize the changes that commonly occur in woman during the first 2 months of pregnancy.
1. Menstrual period stops 2. Breasts swell 3. Need for frequent urination as enlarging uterus puts pressure on bladder 4. Possible nausea 5. Fatigue
Compare fetal alcohol syndrome (FAS) and fetal alcohol effects.
Both caused by consumption of alcohol by the mother during pregnancy and cause many problems, but FAS is more severe.
Samples of tissue from the membrane that encases the fetus are removed and tested; greater risk than amniocentesis
Chorionic villi sampling
Explain the difference between dominant genes and recessive genes.
Dominant - the stronger of a pair of genes; the characteristic it determines will be expressed when it is paired with a recessive gene Recessive - the weaker of a pair of genes; the characteristic it determines will be expressed only if a person has a second recessive gene for the same characteristic
Extra chromosome 21 typically results in mental retardation
Down syndrome
Time span: third through eighth week Development that occurs: embryo develops rapidly; major body systems form; brain begins to control body systems upon implantation, the placenta begins to secrete HCG, which is detected in the mother's urine, and subsequently in a pregnancy test, heart beats by 4th week
Embryonic
Which parent can provide either an X or Y chromosome to the baby? Which chromosome must come from this parent for the child to be female?
Father; X chromosome must come from the father for the child to be a female
Time span: eighth or ninth week through birth Development that occurs: fetus develops buds for teeth and vocal cords, digestive system and kidneys begin to function, movements begin; major organs become ready to function; gains weight
Fetal
Two separate eggs are fertilized by two separate sperm, resulting in two embryos
Fraternal twins
what is DNA?
Genes are made up of a complex molecule called DNA
Time span: conception to 2 weeks Development that occurs: zygote forms and grows by cell division; zygote implants in uterus
Germinal
What is heredity? Name 3 characteristics that can be hereditary.
Heredity is the passing of characteristics from parents to child through gene; physical build, hair color, eye color, size of feet
Explain the difference between a miscarriage and a stillbirth.
Miscarriage - when developing baby dies prior to the 20th week of pregnancy (fairly common, 15%) Stillbirth - if the baby dies after the 20th week (2% of pregnancies)
A fertilized egg from a donor is placed in the woman's uterus
Ovum transfer
Inability of body to process a common protein
PKU
Give three examples of hazardous substances pregnant women should avoid.
Paint, pesticides, and lead
Tissue rich in blood vessels that forms from cells in the uterus. Absorbs oxygen and nourishment from the mother to be transferred to the baby
Placenta
A woman becomes pregnant for a woman who cannot have a baby
Surrogate mother
Lack of a certain blood chemical makes body unable to process certain fats in the brain and nerve cells
Tay-Sachs disease
What is "lightning" and when does it occur?
The baby shifts downward into the birth canal to prepare for birth. It occurs near the end of the 40 weeks of pregnancy.
What is a genome?
The complete genetic blueprint for the creation of a person
What is SIDS?
The sudden death of a baby under one year of age with no clear cause
What are genes?
The units that determine a person's inherited characteristics
What are chromosomes?
Tiny threadlike structures made up of thousands of genes
Sound waves are used to make a video image of the unborn baby; no known risk
Ultrasound/ sonogram
Tube that carries the nourishment and oxygen from the the placenta to the baby
Umbilical cord
Summarize the process of conception.
When an ovum is released from a woman's uterus, it travels through the Fallopian tube to the uterus. Conception occurs if sperm reaches the tube and penetrates and fertilizes the ovum. Ovum lives 12-24 hours. Sperm can fertilize for about 48-72 hours.
If an expectant mother needs X-rays because of an accident, why should she tell the doctors that she is pregnant?
X-rays can harm the baby. Doctors can take precautions to limit the baby's exposure.