Ch 2: Genetic and Environmental Foundations

Question 1

Allele

Answer 1

Two forms of each gene occur at the same place on the chromosomes, one inherited from the mother and one from the father.

Question 2

Autosomes

Answer 2

Means matching pairs (not sex chromosomes). 22 out of 23 pairs of chromosomes are matching pairs.

Question 3

Behavioral Genetics

Answer 3

Is a field devoted to uncovering the contributions of nature and nurture to this diversity in human traits and abilities.

Question 4

Carriers

Answer 4

One that carries and can pass certain traits to their children.

Question 5

Chromosomes

Answer 5

Rodlike structures which store and transmit genetic information.

Question 6

Coparenting

Answer 6

Mutually supporting each other’s parenting behaviors. Such parents are warmer, praise and stimulate their children more.

Question 7

DNA

Answer 7

DNA is a chemical substance made of long, double-stranded molecules that lists like a twisted ladder.

Question 8

Dominant-recessive Inheritance

Answer 8

In heterozygous pairings, only one allele affects the child’s characteristics. It is called dominant; the second allele, which has no effect, is called recessive.

Question 9

Epigenesis

Answer 9

Development results from ongoing, bidirectional exchanges between heredity and all the levels of the environment.

Question 10

Extended-family Households

Answer 10

Parent and child live with one or more adult relatives.

Question 11

Fraternal, or dizygotic twins

Answer 11

Most common type of multiple offspring, resulting from the release and fertilization of two ova.

Question 12

Gametes

Answer 12

Sex cells - when the sperm and ova combine. A gamete contains only 23 chromosomes, half as many as a regular body cell.

Question 13

Gene

Answer 13

Is a segment of DNA along the length of the chromosome.

Question 14

Gene-environment Correlation

Answer 14

Our genes influence the environment to which we are exposed.

Question 15

Gene-environment Interaction

Answer 15

Because of genetic makeup, individuals differ in their responsiveness to the qualities of their environment.

Question 16

Genetic Counseling

Answer 16

Is 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.

Question 17

Genomic Imprinting

Answer 17

Alleles are imprinted or chemically marked through regulatory processes within the genome, in such a way that one pair member (either the mother’s or the fathers’) is activated, regardless of its makeup.

Question 18

Genotype

Answer 18

The complex blend of genetic information determines our species and influences all our unique characteristics.

Question 19

Heritability estimates

Answer 19

Measure the extent to which individual differences in complex traits in a specific population are due to genetic factors.

Question 20

Heterozygous

Answer 20

If the alleles differ. The relationships between the alleles influence the child’s phenotype.

Question 21

Homozygous

Answer 21

If the alleles from both parents are alike, the child will display the inherited trait.

Question 22

Identical, monozygotic twins

Answer 22

When a zygote has started to duplicate separates into two clusters of cells that develop into two individuals and have the same genetic makeup.

Question 23

Incomplete Dominance

Answer 23

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.

Question 24

Kinship Studies

Answer 24

Heritability estimates which compare the characteristics of the family members.

Question 25

Meiosis

Answer 25

A cell division process that results in the formation of gametes (sex cells) which halves the number of chromosomes normally present in body cells.

Question 26

Methylation

Answer 26

When gene expression is altered. 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.

(can explain why identical twins, sometimes display strikingly different phenotypes with age).

Question 27

Mutation

Answer 27

A sudden but permanent change in a segment of DNA. Can result in infant death and impact physical and mental functioning.

Question 28

Niche-picking

Answer 28

The tendency to actively choose environments that complement our heredity.

Question 29

Phenotype

Answer 29

Directly observable characteristics

Question 30

Polygenic Inheritance

Answer 30

When many genes affect the characteristic in question. such as height, weight, intelligence, and personality.

Question 31

Prenatal Diagnostic Methods

Answer 31

Medical procedures that permit detection of developmental problems before birth.

Question 32

Protein-coding Genes

Answer 32

Directly affect our body’s characteristics. Proteins, which trigger chemical reactions throughout the body, are the biological foundation on which our characteristics are built.

Question 33

Public Policies

Answer 33

Laws and government programs designed to improve current conditions.

Question 34

Regulator Genes

Answer 34

Modify the instructions given by protein-coding genes, greatly complicating their genetic impact.

Question 35

Sex Chromosomes

Answer 35

The 23rd chromosome. In females the pair is XX; in males, it is XY.

Question 36

Socioeconomic status

Answer 36

three overlapping variables (1) years of education (2) prestige of one’s job and skill it requires, both of which measure social status; and (3) income, which measures economic states. As SES rises and falls, people face changing circumstances that profoundly affect family functioning.

Question 37

Subculture

Answer 37

Groups of people with beliefs and customs that differ from the larger culture.

Question 38

X-linked inheritance

Answer 38

When a harmful allele is carried on the X chromosome. Males are more likely to be affected because their sex chromosomes do not match.

Question 39

Zygote

Answer 39

When the sperm and ovum unite at conception, the resulting cell is called a zygote and will again have 46 chromosomes.