Genetics and Evolution

Question 1

the nature-nurture question

Answer 1

how do ones genes interact w their surroundings to determine intelligence

Question 2

behavioural genetics

Answer 2

science of how genes and environments combine to generate behaviour

Question 3

adoption study

Answer 3

behavioural genetic research method that compares adopted children to their adoptive and biological parents

Question 4

twin studies

Answer 4

behavioural genetic research method that involves comparison of similarities between identical and fraternal twins

Question 5

quantitative genetics

Answer 5

method of inferring genetic and environmental processes and based on the degree of genetic and environmental similarity among organisms (how biologically related they are)

Question 6

heritability coefficient

Answer 6

(0 to 1). Measures how strongly differences among individuals are related to genetic differences

Question 7

Gene-environment interaction (GxE)

Answer 7

genetic differences affect behaviour under some environmental circumstances but not others
ex: MAOA gene shows predisposition to violence

Question 8

Epigenetics

Answer 8

process in which DNA is modified

Question 9

evolution

Answer 9

certain traits and behaviours developing over time because they are advantageous to our survival

Question 10

natural selection

Answer 10

reproductive success as a consequence of heritable attributes
- we have inherited adaptive psychological processes to ensure success

Question 11

adaptations (2)

Answer 11

traits and behaviours that evolved over time to increase reproduction success

1. survival adaptations - sweat glands to survive in hot temps, fears keep us safe
2. physical survival - adaptations for reproduction and help us compete for mates

Question 12

sexual selection

Answer 12

evolution of characteristics, not because of survival advantage but because of mating advantage
*occurs through 2 processes

Question 13

intrasexual competition

Answer 13

members of one sex compete with each other and the victors gain preferential mating access of opposite sex

Question 14

intersexual selection

Answer 14

if members of one sex are attracted to certain qualities qualities of the other, those desired qualities get passed down
- because their possessor mates more often

Question 15

gene selection theory

Answer 15

genes that are able to encourage the organism to reproduce have an advantage over competing genes

1. influence odds of survival
2. inclusive fitness

Question 16

psychological adaptations

Answer 16

mechanisms of the mind that have evolved to solve specific problems of survival or reproduction
ex: sexual jealousy

Question 17

physiological adaptations

Answer 17

occur in body as a consequence of one’s environment

ex: skin make calluses

Question 18

minimal parental investment

Answer 18

woman (pregnancy) men(simply sex)

• woman choice in mate is much more important
• men engage in more short term casual sexual activity bc the risk is lower

Question 19

men vs woman

Answer 19

men - more likely to regret missed sexual opportunities, lower standards, desire youth and health.
woman- desire mates w resources, wealth, and are willing to share resources.
* both choosy when looking for long term

Question 20

error management theory

Answer 20

evolution of how we think, make decisions, and evaluate uncertain situations.
- predicts that whenever uncertain situations present us w a safer vs more dangerous decision, we will adapt to prefer choice that minimizes cost of errors.

Question 21

epigenetics

Answer 21

study of heritable changes in gene expression or in the cellular phenotype caused by mechanisms other than changes in the underlying DNA sequence

• small chemical tags that sit on chromatin.
• turns genes off (condense) or on (decondense)
• include covalent DNA modifications and post-translational histone modifications

Question 22

the dynamic epigenome

Answer 22

DNA wrapped around group of 8 proteins called histones

Question 23

nucleosome

Answer 23

DNA & histone combination

• structural solution for maintaining and accessing genome
• factors alter likelihood that a gene will be expressed or silenced

Question 24

DNA methylation

Answer 24

Best understood epigenetic modification influencing gene expression

• occurs in cytosine residues
• enzymes that form are DNA methyltransferase (DNMT’s) which catalyzes the transfer of methyl group to the cytosine
• usually results in gene silencing
• powerful regulatory mechanism- ensures genes are only expressed when needed
• mediates effects of early environment in both rodents and humans

Question 25

histone acetylation

Answer 25

associated with gene activation and increased gene expression
mediated by: histone acetyltransferases (increase gene expression) & histone deacetylases(decrease gene expression)

Question 26

Childhood experiences

Answer 26

development of child relies on many factors

• parents, parents investment…..
• high investment = low stress
• low investment = high stress

Question 27

low parental investment

Answer 27

= high stress growing up. Decreased histone acetylation, DNA methylation of glucocorticoid receptor

Question 28

HDAC inhibitor trichostatin A, TSA or methyl donor L-methionine

Answer 28

• can eliminate stress hormone responses

- pharmacological treatment

Question 29

childhood nutrition and the epigenome

Answer 29

nutrients - can reverse/change DNA methylation&histone modifications.

• can modify expression of critical genes
• can directly inhibit enzymes that catalyze DNA methylation & histone
• by altering availability of those substrates necessary for those enzymatic reactions

Question 30

Rett syndrome

Answer 30

mutation in DNA sequence in a gene called MECP2
MECP2 - reads the DNA sequence, checking for DNA methylation
- supports dendritic and synaptic development and hippocampus-dependent memory

Question 31

CBP

Answer 31

mutations in DNA sequence in a gene

- perform poorly in cognitive task when CBP mutation

Question 32

depression

Answer 32

epigenetics alter chromatic structure for gene expression
- post mortem depression
HDAC inhibitors - against depression