Biological Basis of Behavior

Question 1

Importance of adaptation

Answer 1

inherited characteristics increase in population via natural selection because it solved a problem, behavioral or physical. Human nature reflects adaptive demands of ancient ancestors

Question 2

Nature vs. nurture

Answer 2

Nature is the biology, genes, while nurture is the environment

Question 3

Trait
Heredity
Genetics

Answer 3

trait: any characteristic that can be passed down
heredity: the act of passing traits from parent to offspring
genetics: the study of heredity

Question 4

Importance of natural selection

Answer 4

heritable characteristics that provide a survival or reproductive advantage passed down more frequently, selected over time, fuels evolution

Question 5

Evolutionary noise

Answer 5

neutral variations, traits may or may not become advantageous depending on the environment

Question 6

Fitness

Answer 6

reproductive success relative to average in population, variations fuel evolutionary change

Question 7

Genetic drift

Answer 7

random fluctuation in gene frequencies over generations, due to chance

Question 8

Mutation

Answer 8

spontaneous heritable changes to DNA, in individuals, most are silent, then disadvantageous and then advantageous

Question 9

Gene flow

Answer 9

change in gene frequencies due to immigration and emigration. Gene pools may be different because of mutations, genetic drift, and natural selection, but gene flow counterbalances these by “reintroducing” the genes into the gene pools. When there is minimal gene flow, causes diverging, can result in new species

Question 10

Chromosomes

Answer 10

strands of DNA, carry genetic info

every human cell, except sex cells have 46

Question 11

Genes

Answer 11

DNA segments, key functional units in hereditary transmission

Question 12

Homozygous condition

Answer 12

two genes in pair are the same

Question 13

Heterozygous condition

Answer 13

two genes in pair are different

Question 14

Genotype

Answer 14

genetic makeup, is fixed

Question 15

Phenotype

Answer 15

the expression of the genotype, can be changed

Question 16

Polygenic traits

Answer 16

can be influenced by more than one gene

Question 17

3 modes of genotype expression

Answer 17

• dominant and recessive
• blend or average
• both

Question 18

Genome

Answer 18

all genetic material of an organism

Question 19

Family studies

Answer 19

asses hereditary influence by examining blood relatives to see resemblance of trait, indicate if trait runs in families, but not definitely, as similar environment might have affected

Question 20

Twin studies

Answer 20

asses hereditary influence by comparing resemblance of identical (monozygous) and fraternal twins (dizygotic). Trait is hereditary if more similarity in identical than fraternal

Question 21

Adoption studies

Answer 21

asses hereditary influence by examining resemblance between adoptive and biological parents

Question 22

Gene mapping

Answer 22

process to determine location and chemical sequence of specific genes in specific chromosomes, used for dichotomous traits which are governed by a single gene pair

Question 23

Epigenetics

Answer 23

genetic and environmental factors are inextricably intertwined, study of heritable changes in gene expression that do not involve modifications to DNA sequencing

Question 24

Histones

Answer 24

proteins, DNA tightly packed around them

Question 25

Methylation of histones

Answer 25

stop gene expressions

Question 26

Relative influence of genes and environment on psychological outcomes

Answer 26

impact of genetic makeup depends on environment, impact of environment depends on genetic makeup