- active genotype-environment correlation
- event in which individuals select particular environments or experiences based on their genotype
- age of viability
- age at which a fetus born prematurely (before the thirty-seventh week of pregnancy) may have a chance of survival outside the womb, usually with intensive medical intervention
- allele
- variant of a gene
- amniocentesis
- test in which a needle is inserted through the mother’s abdomen to take a sample of the amniotic fluid and look for chromosomal disorders and some types of genetic defects
- Apgar test
- test administered to a newborn one minute after delivery and again at five minutes after delivery to assess their condition after birth; detects major abnormalities
- attachment
- the emotional connection a child feels toward their caregiver based on consistency and quality of care
- autosome
- chromosome in the nucleus that is not a sex chromosome
- behavioral genetics
- interdisciplinary field that focuses on the study of heredity-behavior relationships
- blastocyst
- small cluster of a few hundred cells formed shortly after conception
- bonding
- one-way relationship consisting of a caregiver’s emotional connection to the infant
- cephalocaudal growth
- growth that occurs from head to feet, allowing a fetus to grow longer
- cesarean birth
- medical procedure in which a doctor makes an incision in a birth mother’s abdomen and uterus to deliver the fetus and placenta
- chorionic villus sampling
- prenatal test that uses a placental tissue sample to determine whether chromosomal or genetic disorders are present in the fetus
- chromosomal disorder
- condition that occurs with an incorrect number of chromosomes or results from structural abnormalities of the chromosome
- chromosome
- strand of the DNA sequence in the nucleus of an individual’s cells that carries genes transmitting hereditary information
- codominant trait
- characteristic observed when two different alleles are expressed at the same time
- conception
- union of sperm and ovum (egg)
- congenital disorder
- any abnormality present at birth
- contraception
- method used to reduce chances of conception
- dizygotic twins
- (or fraternal) twins that occur when two ova are fertilized at the same time
- DNA (also, deoxyribonucleic acid)
- molecule that contains an individual’s genetic information
- DNA methylation
- process whereby methyl groups are added to or removed from DNA, potentially causing changes in gene expression
- dominant trait
- characteristic observed when only one copy of the allele is needed to express a phenotype
- embryonic period
- second developmental period of pregnancy, during which the blastocyst becomes an embryo and organogenesis begins
- evocative (or reactive) genotype-environment correlation
- event in which an individual’s genetically influenced traits elicit an environmental response
- failure to thrive
- situation in which a premature infant’s height and weight are below the third percentile
- fallopian tube
- part of the female reproductive system where egg is released and through which it travels to reach the uterus
- fetal period
- last developmental period of pregnancy, during which the fetus grows quickly
- gamete
- sex cell, the ovum or sperm, that carries twenty-three chromosomes
- gene
- hereditary unit composed of a specific DNA sequence that occupies a specific location along a chromosome in an individual
- genome
- complete sequence of an organism’s DNA
- genotype
- individual’s particular genetic composition of alleles at specific locations
- genotype × environment interaction
- event that occurs when the expression of a genotype depends on the environment
- germinal period
- first developmental period of pregnancy, when conception occurs and the blastocyst travels through the fallopian tubes to the uterus
- heterozygous
- trait in which an individual receives different alleles from each biological parent for a given trait
- homozygous
- trait in which an individual receives identical alleles from each biological parent for a given trait
- hormone
- chemical released by glands that controls and regulates bodily functions
- implantation
- process in which a blastocyst embeds within the uterus
- in vitro fertilization (IVF)
- form of assisted reproductive technology (ART) in which a fertilized egg is transferred into a uterus for implantation
- incomplete dominance
- form of genetic expression in which both inherited alleles are partially expressed
- infertility
- inability to successfully conceive after one year of trying
- low birth weight
- birth weight less than 5 lb 8 oz
- mass-to-specific growth
- growth in which large movements and structures develop before smaller or more specified movements and structures
- meiosis
- type of cell division that occurs during gamete production and results in their containing only one member of each chromosome pair
- mitosis
- type of cell division in which a cell duplicates itself and its DNA
- monozygotic twins
- (or identical) twins that occur when a zygote splits into two clusters of cells, creating two genetically identical zygotes
- multifactorial inheritance
- phenotype resulting from multiple genetic and environmental factors
- natural childbirth
- a childbirth method using nonpharmaceutical techniques to help minimize pain and the need for medical intervention for the birth mother
- neonatal behavioral assessment scale (NBAS)
- test assessing a newborn’s neurological and physical health, typically given three to four days after birth
- organogenesis
- the formation of organs during the embryonic period
- ovary
- part of the female reproductive system that releases eggs (ova)
- oxytocin
- hormone that helps initiate labor and plays a role in forming bonds with others
- parental leave
- policies that allow parents to take time off work, often paid, to care for a newborn for a period of time
- passive genotype-environment correlation
- event that occurs when parents provide offspring with both genes and environment
- phenotype
- observable expression of someone’s genome
- placenta
- a temporary organ connecting the uterus to the umbilical cord that provides respiration and nourishment for the embryo in addition to eliminating metabolic wastes
- pleiotropy
- most common form of genetic expression in which one gene influences multiple traits
- polygenic trait
- trait influenced by several genes
- preterm (premature/preemie) infant
- any infant born before thirty-seven weeks’ gestation and weighing less than 5.5 lb
- proximodistal growth
- growth that occurs from the center of the body outward
- recessive trait
- trait that requires two identical alleles to be expressed
- single-gene disorder
- condition caused by variation in a single gene
- spontaneous abortion
- (also, miscarriage) loss of a pregnancy during the first twenty weeks
- teratogen
- disease, drug, or environmental agent that can harm an embryo or fetus physically or influence health or behavior after birth
- testes
- parts of the male reproductive system that help create and sustain sperm
- umbilical cord
- a flexible tube connecting the embryo and the placenta
- urethra
- part of the human reproductive system that, in males, transports and releases sperm
- uterus
- part of the female reproductive system where a fertilized egg implants to develop
- vagina
- muscular canal that connects the uterus to the outside of the female body
- vas deferens
- tube that transports sperm from the testes to the urethra
- vulva
- external aspects of the female reproductive system including the labia, clitoris, and vaginal opening
- zygote
- single cell formed at conception and consisting of forty-six chromosomes, twenty-three from each parent