1.1 - Unit 1 Biological Bases of Behavior

Nature vs Nurture controversy

do genes or environment play a bigger role in our development?

Natural Selection

The principle that inherited traits that enhance survival and reproduction are more likely to be passed on to future generations. (species that do not adapt, do not survive)

how was eugenics used by society

selectively breeding humans to promote desired traits or prevent certain traits from being passed on

Evolutionary Psychology

study of the evolution of behavior and the mind, using principles of natural selection

Behavior Genetics

study of the relative power and limits of genetic influences on behavior

4 basic concepts from Darwin’s principle of natural selection

• offspring competes for survival

• certain biological and behavioral variation increases an organism’s reproductive survival chances in the particular environment

• offspring that survive are more likely to pass on their genes

• over time, population characteristics may change

Mutations

Random errors in gene replication that leads to a change

how much of a genetic difference is there between populations? How much variation is there between members of the same population?

5% genetic difference overall between populations and 95% variation within populations

evolutionary psychologists

focus on human similarities

behavior geneticists

focus on genetic and environmental roots of human differences

environment

every non genetic influence

heredity

genetic transfer of characteristics from parents to offspring

genes

biochemical units of heredity

genome

complete instructions for making an organism

how many chromosomes do we get from each parent?

23 (46 in total)

what are chromosomes made of?

coiled chain of the molecule DNA

How does the environment impact genes?

it activates genes, when genes are activated they provide the code for creating protein molecules

How do scientists use genetics to prevent or treat diseases that have a genetic basis?

gene editing technologies

polygenetic

influenced by many genes of small effect

identical twins

same DNA, same sex, one egg (monozygotic)

fraternal twins

different DNA, might be same or opposite sex, two eggs (dizygotic)

what finding that has come out of studies dealing with personality traits with adopted children?

People who have been adopted are more similar to their biological parents than to their adoptive parents

most important similarity for our species?

adaptive capacity

interaction

interplay that occurs when the effect of one factor (ex. environment) depends on another factor (ex. heredity)

epigenetic

study of molecular mechanisms by which environments can influence genetic expression (without DNA change)en

3 examples of environmental factors that can affect epigenetic molecules that regulate gene expression

• diet

• drugs

• stress

3 ways that epigenetic provides a possible mechanism that can last a lifetime

• childhood trauma

• poverty

• malnutrition