Psych Ch. 3 Biopsych

Human Genetics

Study of genetic factors influencing behavior.

Sickle-cell Anemia

Genetic disease providing malaria resistance.

Genetic Variation

Differences in genes among individuals.

Chromosomes

Structures containing genetic material, 23 pairs each.

Genes

Sequences of DNA determining traits.

Allele

Specific variant of a gene.

Phenotype

Observable physical characteristics of an organism.

Dominant Allele

Allele that expresses trait over another.

Recessive Allele

Allele that expresses trait only when homozygous.

Homozygous

Having two identical alleles for a trait.

Heterozygous

Having two different alleles for a trait.

Polygenic Traits

Traits controlled by multiple genes.

Mutation

Permanent change in a gene.

Gene-Environment Interaction

Influence of environment on gene expression.

Identical Twins

Twins from one fertilized egg.

Fraternal Twins

Twins from two different fertilized eggs.

Neurons

Cells that transmit nerve impulses.

Neurotransmitter

Chemical messenger for neuron communication.

Resting Potential

Electrical charge difference across neuron membrane.

Action Potential

Electrical signal traveling down a neuron.

Synapse

Junction between two neurons.

Agonist

Chemical that mimics neurotransmitter action.

Antagonist

Chemical that blocks neurotransmitter action.

Reuptake Inhibitors

Prevent reabsorption of neurotransmitters.

Biological Perspective

Focus on biological factors in psychology.

Neural Communication

Process of signal transmission between neurons.

Neurotransmitter Balance

Equilibrium of neurotransmitter levels in the brain.

Membrane Potential

Voltage difference across a neuron's membrane.