Ch. 3 Biopsychology

Chromosome

collections of genes

Deoxyribonucleic acid (DNA)

contain genetic code; make up genes

Gene

segments of DNA that encode specific traits/chars

• alleles are diff version of the gene

Dominant-Recessive Genes

a single dominant gene will “win” when paired w/ recessive gene

• Must inherit 2 copies of recessive gene to show trait

• EX: eye color

Polygenic

characteristic is product of interaction of many different genes

• EX: skin, eye color

Mutation

sudden, permanent change in gene

• EX: radiation, mercury, cell division

• Either lead to pos or neg changes

Range of reaction

genes set up a range of possibilities; environment determines outcome within that range

• Heigh, nutrition, healthcare

Genetic environmental correlation

genes influence environment, and environment influences expression of genes

• Passive, evocation, active

Passive gene–environment correlation

the association between the genotype a child inherits from their parents and the environment in which the child is raised

• EX: Musically inclined parent has a lot of music in home

Evocative (or reactive) gene–environment correlation

happens when an individual's (heritable) behavior evokes an environmental response

• EX: Physically attractive people receive better social treatment

Active gene–environment correlation

occurs when an individual possesses a heritable inclination to select environmental exposure

• EX: physically gifted people chose to play sports

Epigenetics

how environment, other factors can change way genes are expressed

• EX: identical twins with different outcomes

Nervous System

allows for communication in brain and rest of body

• Neuron is the basic unit of NS (send + receive)

Glial Cells

scaffolding for neurons; may aid in memory; clear debris

What are the parts of a neuron (7)

1. Semipermeable membrane

2. Dendrite (info receive - pass)

3. Soma/Cell body (fire potential)

4. Axon (impulse away)

5. Synaptic vesicles (sac of neurotransmitters)

6. Myelin sheath (insulate axon)

7. Nodes of Ranvier

Neurotransmitters

released by transmitting neuron; cause changes in receiving neuron

Action potential

the impulse that travels from the cell body to the end of the axon

• Involves changes in the electrical potential of the membrane of the axon

Synaptic Cleft/Gap

tiny space between neurons

• synaptic vesicles open to spill neurotransmitters here

Receptors

molecules in membrane of receiving neuron

• Key in a lock = the neurotransmitter has to be the correct physical shape in order to bind with a particular receptor.

2 effects of neurotransmitters

1. Excitatory: neuron more likely to fire action pot

2. inhibitory: less likely to fire

All-or-none response

neuron either fires or it doesn’t - no partial fire

• i.e. like turning on a light

Reuptake

extra neurotransmitters reabsorbed by releasing neuron

• i.e. like putting cheetos back in bag

Refactory period

it cannot fire another action potential until it undoes the physical changes caused by the previous action potential.