Biopsychology Vocabulary Flashcards

Vocabulary terms covering key concepts from Biopsychology (Chapter 3): genetics, neurons, neurotransmitters, brain structures, and imaging.

Biopsychology

The study of the biological basis of behavior, including genetics, neurons, neurotransmitters, and the nervous and endocrine systems.

Genes

Units of heredity made of DNA that influence physiological and psychological traits.

DNA

Deoxyribonucleic acid; the helix-shaped molecule that carries genetic information.

Chromosome

A long strand of DNA that carries many genes.

Gene

A DNA sequence that codes for a trait or part of a trait.

Allele

A variant form of a gene.

Genotype

An individual's genetic makeup inherited from the parents.

Phenotype

An individual's observable traits resulting from the genotype and environment.

Dominant allele

An allele that expresses its trait even if only one copy is present.

Recessive allele

An allele that is expressed only when two copies are present (homozygous).

Heterozygous

Having two different alleles for a gene (Aa).

Homozygous

Having two identical alleles (AA or aa).

Polygenic trait

A trait controlled by more than one gene.

Mutation

A sudden, permanent change in a gene; can be harmful or beneficial.

Genetic variation

Differences in the genetic makeup among individuals of a species.

Nature vs nurture

The debate about how genes and environment shape behavior and traits.

Epigenetics

The study of how gene expression is influenced by environmental factors without changing the DNA sequence.

Gene-environment interaction

The idea that genes and environment influence each other to shape behavior.

Range of reaction

The genetic boundaries within which environment determines where an individual falls on a trait continuum.

Nervous system

Network of neurons and glia that processes information and coordinates responses.

Central nervous system (CNS)

Brain and spinal cord; the body's major information processing center.

Peripheral nervous system (PNS)

Nerves outside the CNS that connect the CNS to the body.

Somatic nervous system

PNS division that relays sensory and motor information for voluntary movement.

Autonomic nervous system

PNS division that regulates internal organs and glands without conscious control.

Sympathetic nervous system

Autonomic division that prepares the body for stress (fight or flight).

Parasympathetic nervous system

Autonomic division that relaxes the body after stress (rest and digest).

Homeostasis

A state of internal balance maintained by the body.

Neuron

The basic nerve cell; the primary unit of the nervous system.

Dendrite

Branch-like structures that receive signals from other neurons.

Axon

Long fiber that transmits signals away from the neuron.

Myelin sheath

Fatty insulation around an axon that speeds signal transmission.

Terminal buttons

Endings of axons that release neurotransmitters into the synapse.

Synapse

The tiny gap between neurons where signals are transmitted.

Neurotransmitters

Chemical messengers that cross the synapse to affect the next neuron.

Receptors

Proteins on dendrites that bind neurotransmitters.

Synaptic vesicles

Storage sacs in the terminal button that release neurotransmitters.

Resting potential

The neuron's baseline electrical charge when not firing.

Depolarization

A decrease in the membrane's polarization, making firing more likely.

Hyperpolarization

An increase in polarization, making firing less likely.

Threshold of excitation

The level of depolarization required to trigger an action potential.