Chapter 2 Flashcards
Phenotypes
Directly observable characteristics.
Genotype
The complex blend of genetic information that determines our species and influences all our unique characteristics.
Chromosomes
Rod-like structures which store and transmit genetic information.
Deoxyribonucleis Acid (DNA)
What chromosomes are made of.
Gene
A segment of DNA along the length of the chromosome.
Protein-Coding Genes
Directly affect the body’s characteristics.
Regulator Genes
Modify the instructions given by protein-coding genes.
Gametes
Sex cell - sperm or ovum.
Meiosis
Process by which gametes are formed through cell division.
Zygote
Product of sperm and ovum uniting at conception.
Fraternal (Dizygotic) Twins
The most common type of multiple offspring, resulting from the release and fertilization of two ova.
Identical (Monozygotic) Twins
A zygote that has started to duplicate separates into two clusters of cells that develop into two individuals. Have the same genetic makeup.
Allele
The form of gene which you get from each of your parents.
Homozygous
If alleles from both parents are alike, the child will display the inherited trait.
Heterozygous
If the alleles from both parents differ the relationships between the alleles influence the phenotype.
Dominant-Recessive Inheritance
Only one allele affects the child’s characteristics. It is called dominant; the second allele, which has no effect, is called recessive.
Happens in heterozygous pairings.
Carriers
Heterozygous individuals with just one recessive allele can pass that trait to their child.
Incomplete Dominance
A pattern of inheritance in which both alleles are expressed in the phenotype, resulting in a combined trait, or one that is intermediate between the two.
X-Linked Inheritance
When a harmful allele is carried on the X chromosome. Males are more likely to be affect because their sex chromosomes do not match.
Genomic Imprinting
Alleles are imprinted, or chemically marked through regulatory processes within the genome, in such a way that one pair member (either mother or father’s) is activated, regardless of its makeup.
Mutation
A sudden but permanent change in a segment of DNA.
Polygenic Inheritance
Many genes affect the characteristic in question.
Genetic Counseling
A communication process designed to help couples assess their chances of giving birth to a baby with a hereditary disorder and choose the best course of action in view of risks and family goals.
Prenatal Diagnostic Methods
Medical procedures that permit detection of developmental problems before birth.
Coparenting
Mutually supporting each other’s parenting behaviors.
Socioeconomic Status
Combines three related but not completely overlapping, variables which measure economic status:
- ) Years of Education
- ) Prestige of One’s Job & Skill it Requires
- ) Income
Subcultures
Groups of people with beliefs and customs that differ from those of the larger culture.
Extended-Family Households
In which parent and child live with one or more adult relatives.
Public Policies
Laws and government programs designed to improve current conditions.
Behavioral Genetics
A field devoted to uncovering the contributions of mature and nurture to this diversity in human traits and abilities.
Heritability Estimates
Measure the extent to which individual differences in complex traits in a specific population are due to genetic factors.
Kinship Studies
Compare the characteristics of family members.
Gene-Environment Interaction
Which means that because of their genetic makeup, individuals differ in their responsiveness to qualities of the environment.
Gene-Environment Correlation
Our genes influence the environments to which we are exposed.
Niche-Picking
The tendency to actively choose environments that complement our hereditary.
Epigenesis
Which means development resulting from ongoing, bidirectional exchanges between heredity and all levels of the environment.
Methylation
A biochemical process triggered by certain experiences, in which a set of chemical compounds (called a methyl group) lands on top of a gene and changes its impact, reducing or silencing its expression.
