CH.2 - Heredity, Prenatal Development, and Birth

Behavioral Genetics

The study of the interplay between the genetic and environmental contributions to behavior

Epigenetics

Studies modification in DNA that affect gene expression that are passed on when cells divide

Germinal Period

Ab 14 days in length; Zygote is formed after fertilization within the fallopian tube, containing the combined genetic info from both parents

Blastocyst

The 100 cells formed during the germinal period, containing both inner and outer group cells

Inner group cells

Cells in the blastocyst that will become the embryo

Outer group cells

Cells in the blastocyst that are not specified in the provided text

Embryonic Period

Starting the 3rd week, the blastocyst has implanted within the cellular wall; it is during this stage the organism is most vulnerable to damage

Fetal Period

Major structures are still developing; has all body parts and genitalia

Neurogenesis

The formation of neurons, except for the hippocampus that develops neurons throughout life

Neural migration

Completed in the cerebral cortex by 24 weeks

Gray matter

Regions of the brain that contain the cell bodies

White matter

The axons that form the neural pathways

Fetal Alcohol Spectrum Disorder (FASD)

Increases the chances of a child having poor judgment, poor impulse control, higher rates of ADHD, learning issues, and lower IQ scores

Neonatal Abstinence Syndrome

When babies get addicted to drugs before birth and go through drug withdrawal after birth

Toxoplasmosis

Infection caused by the tiny parasite Toxoplasma gondii that can cause premature birth, stillbirth, and birth defects in the eyes and brain

Gestational Diabetes

A condition where 7% of pregnant women develop too much glucose in the bloodstream, usually tested at 24-28 weeks

Hypertension

A condition in which the pressure against the wall of the arteries becomes too high

Rh Disease

A form of anemia that occurs when mothers who are Rh-negative have a baby

Ultrasound

A test where sound waves observe the fetus, used to check for problems

Amniocentesis

A procedure where a needle is used to withdraw a small amount of amniotic fluid and cells from the sac surrounding the fetus

Chorionic Villus Sampling

A procedure where a small sample of cells is taken from the placenta and tested

Ectopic Pregnancy

When the zygote becomes attached to the fallopian tube before it reaches the uterus

Preeclampsia

Characterized by a sharp rise in blood pressure, leakage of protein into the urine, and swelling of the hands, feet, and face during the 3rd trimester

Spontaneous Abortion

When the body aborts due to abnormalities, typically before the 12th week

The Lamaze Method

Teaches a woman to be in control during the process of delivery

Stages of Birth

The 1st stage lasts about 30 seconds and is spaced 15 to 20 minutes apart; the 2nd stage takes about 10-40 minutes

Episotomy

An incision made in the tissue between the vaginal opening and anus to avoid tissue tearing.

Epidural Block

A regional analgesic used during labor that alleviates most pain in the lower body without slowing labor.

C-section

A surgery to deliver the baby through the mother's abdomen.

Induced Birth

When a baby needs to be delivered before labor begins due to health concerns for the baby or mother.

Anoxia

Temporary lack of oxygen in the brain.

Low birth weight

Considered low if the baby is less than 5 lbs, increasing risk for infection and respiratory issues.

Very low birth weight

A weight of 2 lbs or less, increasing the chance of cerebral palsy.

Preterm

A newborn born at less than 37 weeks gestation.

Small-for-date infants

Infants with birth weight below expectation based on gestational age.

Baby Blues

Feelings of sadness occurring 3-5 days after childbirth, typically disappearing within 10 days.

Postpartum Depression

A type of depression occurring during pregnancy or within 4 weeks after childbirth.

Postpartum Anxiety

Heightened anxiety and stress in new mothers due to increased empathy and bonding hormones.

Gene

The building block of nature, specific sequences of nucleotides that are recipes for making proteins.

Chromosomes

Human cells contain 46 chromosomes or 23 pairs, one from each parent.

Mitosis

The process where a cell's nucleus makes an exact copy of its chromosomes and splits into two new cells.

Meiosis

The process where gametes' chromosomes duplicate and then divide twice, resulting in 4 cells with half the genetic material.

Autosomes

22 pairs of chromosomes that remain similar in length.

Genotype

The sum total of all the genes a person inherits.

Phenotype

The features that are actually expressed.

Heterozygous

The different versions of a gene from each parent.

Homozygous

When an individual displays the same exact characteristic.

Dominant

A trait that expresses itself in the phenotype even when paired with a different version of the gene.

Recessive

A gene that expresses itself only when paired with a similar version of the gene.

Carriers

Individuals with one recessive gene who are unaffected by the recessive trait.

Dizygotic twins

Fraternal twins that develop from two separate eggs.

Monozygotic twins

Identical twins that develop from a single fertilized egg.

Chromosomal Abnormality

Occurs when a child inherits too many or too few chromosomes.

Trisomy 21

A condition where there are three copies of chromosome 21, commonly known as Down Syndrome.

Turner syndrome

Occurs when part or all of one of the X chromosomes is lost, resulting in an XO composition.

Klinefelter syndrome

Occurs when an extra X chromosome is present in the cells of a male, resulting in XXY.

Genetic Counseling

A service that assists individuals in identifying, testing for, and explaining potential genetic conditions.