Portage PSY 101 Module 2

A complete list of vocabulary terms and definitions covering genetics, the nervous system, cellular mechanisms, neurotransmitters, endocrine glands, and brain structures.

Allele

An alternative form of a gene.

Trait

Features or characteristics of a person

Dominant Allele

Observable and tend to be expressed over recessive alleles

Recessive Allele

Only expressed when a dominant allele isn't

Homozygous

Two copies of the same allele

Heterozygous

Two different alleles

Phenotype

Physical expression of genotype

Genotype

Genetic makeup of an organism

Chromosomes

Threadlike structures of genetic material that come in 23 pairs, one of each pair from father/mother

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

Primary methods of how genetic and heritability info is obtained (3)

Family studies, Adoption studies, Twins that were reared apart studies

Family studies

Examine genetic relatives to see how the closeness of genetic relationships corresponds to various traits

Adoption studies

Assess hereditary influence by examining the resemblance between adopted children and both their biological and their adoptive parents.

Identical twins reared apart studies

Assesses how most of the variation in personality is from factors other than genetics.

2 branches of autonomic nervous system

sympathetic and parasympathetic

2 main branches of the nervous system

central nervous system (CNS), Peripheral Nervous System (PSN)

Central Nervous System

Made up of the brain and spinal cord

Parasympathetic Nervous System

A set of nerves that helps the body return to a normal resting state

Soma

cell body of a neuron and contains the nucleus of the cell

Dendrites

Branchlike parts of a neuron that are specialized to receive information.

Axon

Transmits information out of the neuron, usually just one of these per neuron

Synapse

A junction where information is transmitted from one neuron to the next. Release neurotransmitters

Sensory Neurons (afferent)

Carry information from the senses to the brain

Motor Neurons (efferent)

Carry outgoing information from the brain to the body

Interneurons

Relay messages among sensory, motor and other interneurons

Action Potential

A bioelectrical neural impulse; a brief electrical charge that travels down an axon

Resting Potential

The state of an inactive neuron when not firing a neural impulse

All-or-none principle

The law that the neuron either fires at 100% or not at all

Repolarization

Na channels close and K channels open allowing K out of the cell, dropping the membrane potential

Depolarization

Na channels open allowing Na into cell causing the interior to become more positive.

Neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons to relay messages

Reuptake

a neurotransmitter's reabsorption by the pre-synaptic neuron

Dopamine

A neurotransmitter associated with movement, attention, learning and the brain's pleasure and reward system.

Serotonin

A neurotransmitter that affects hunger,sleep, arousal, and mood.

Endorphins

A neurotransmitter that relieves pain "morphine within".

Endocrine system

Comprised of glands that secrete hormones that regulate processes such as growth, reproduction, and nutrient use (metabolism) by body cells.

Pituitary

"Master gland" that keeps others under control

Thyroid

Regulates metabolism and growth

Adrenals

Regulates fight or flight response, metabolism and arousal.

Pancreas

Regulates glucose

Ovaries

Regulates development of female sexual characteristics

Testes

Regulates development of male sexual characteristics

Brain stem and cerebellum

Bottom layer at the base of the brain

Limbic system

Middle layer of the brain

Cerebrum

Top layer of the brain / Area of the brain responsible for all voluntary activities of the body

Medulla (brain stem & cerebellum)

The base of the brainstem; controls heartbeat and breathing

Cerebellum (brain stem & cerebellum)

The "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance

Thalamus (brain stem & cerebellum)

the brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

Basal Ganglia (brain stem & cerebellum)

structures in the forebrain that help to control movement

Hippocampus (limbic)

Long term memory

Hypothalamus (limbic)

Below thalamus; it directs several maintenance activities such as eating, drinking, body temperature.

Cerebral Cortex

Grey cell matter covering the cerebrum

Corpus Callosum

A broad band of nerve fibers joining the two hemispheres of the brain.

Frontal Lobe (cerebral cortex)

The lobe at the front of the brain associated with movement, decisions and personality

Prefrontal cortex

the frontmost portion of the frontal lobes, important for attention, decisions, and personality

Parietal lobe (cerebral cortex)

Sensory info; touch, pressure, temp, and pain

Occipital lobe (cerebral cortex)

Visual processing

Temporal lobe (cerebral cortex)

sound processing & speech production

Neuroplasticity

Ability within the brain to constantly change both the structure and function of many cells in response to experience or trauma