AP Psychology: Heredity, Nervous System & Neural Transmission

Heredity (Nature)

The genetic transmission of characteristics from parents to offspring.

Environment (Nurture)

The external factors and influences that affect an individual's development and behavior.

Dizygotic/Fraternal Twins

Twins that develop from two separate fertilized eggs and share about 50% of their genes.

Monozygotic/Identical Twins

Twins that develop from a single fertilized egg that splits into two, sharing 100% of their genes.

Evolutionary Psychology

The study of how evolutionary principles such as natural selection influence human thoughts, feelings, and behaviors.

Behavioral Genetics

The field of study that examines the role of genetic and environmental influences on behavior.

Natural Selection

The process by which organisms better adapted to their environment tend to survive and produce more offspring.

Epigenetics

The study of changes in gene expression that do not involve alterations to the underlying DNA sequence.

Eugenics

A controversial movement aimed at improving the genetic quality of a human population through selective breeding.

Heritability

A measure of how much of the variation in a trait can be attributed to genetic differences among individuals.

Endocrine System

A collection of glands that produce hormones to regulate metabolism, growth, and other bodily functions.

Hormones

Chemical messengers produced by glands in the endocrine system that regulate various physiological processes.

Pituitary Gland

A small gland located at the base of the brain that produces hormones regulating various bodily functions.

Adrenaline

A hormone released by the adrenal glands that increases heart rate and energy levels during stress.

Leptin

A hormone produced by fat cells that helps to regulate energy balance and inhibit hunger.

Ghrelin

A hormone produced in the stomach that stimulates appetite and promotes food intake.

Melatonin

A hormone that regulates sleep-wake cycles, produced by the pineal gland.

Oxytocin

A hormone involved in social bonding, reproduction, and childbirth.

Nervous System

The network of nerve cells and fibers that transmits signals between different parts of the body.

Central Nervous System

The part of the nervous system consisting of the brain and spinal cord.

Peripheral Nervous System

The part of the nervous system outside the brain and spinal cord, consisting of sensory and motor neurons.

Somatic Nervous System

The part of the peripheral nervous system that controls voluntary movements of skeletal muscles.

Autonomic Nervous System

The part of the peripheral nervous system that controls involuntary bodily functions, such as heartbeat and digestion.

Sympathetic

The division of the autonomic nervous system that prepares the body for fight-or-flight responses.

Parasympathetic

The division of the autonomic nervous system that promotes rest-and-digest activities.

Types of Neural Cells

Different types of cells in the nervous system, including neurons and glial cells.

Neurons

The fundamental units of the nervous system that transmit information through electrical and chemical signals.

Sensory Neurons

Neurons that carry signals from sensory receptors to the central nervous system.

Motor Neurons

Neurons that transmit signals from the central nervous system to muscles or glands.

Interneurons

Neurons that connect sensory and motor neurons within the central nervous system.

Glial Cells

Supportive cells in the nervous system that provide structural support, nourishment, and protection for neurons.

Parts of the Neuron

The main components of a neuron, including dendrites, soma, axon, and terminal branches.

Dendrites

Branch-like structures of a neuron that receive signals from other neurons.

Soma (Cell Body)

The central part of a neuron that contains the nucleus and organelles.

Axon

The long, slender projection of a neuron that transmits electrical impulses away from the cell body.

Myelin Sheath

An insulating layer around the axon that speeds up neural transmission.

Terminal Branches/Buttons

The endpoints of an axon that release neurotransmitters to communicate with other neurons.

Receptor Sites

Locations on the postsynaptic neuron where neurotransmitters bind to initiate a response.

Synapses/Synaptic Gap

The small space between neurons where neurotransmitters are released and received.

Neural Transmission

The process by which signals are transmitted along neurons through electrical and chemical means.

All-or-Nothing Principle AKA Response

The principle stating that a neuron either fires completely or not at all, with no partial signals.

Resting Potential

The electrical charge difference across the neuron's membrane when it is not actively transmitting a signal.

Depolarization

The process during which the neuron's membrane potential becomes less negative, leading to an action potential.

Threshold

The level of stimulation required to trigger an action potential in a neuron.

Action Potential

A rapid change in the electrical charge of a neuron that occurs when it fires.

Refractory Period

The time following an action potential during which a neuron cannot fire again.

Reuptake

The process by which neurotransmitters are reabsorbed by the presynaptic neuron after transmitting a signal.

Agonist AKA Reuptake Inhibitor

A substance that enhances the effect of a neurotransmitter by increasing its availability in the synapse.

Antagonist

A substance that blocks or inhibits the action of a neurotransmitter.

Spinal Reflexes/Reflex Arc

The neural pathway that mediates a reflex action, involving sensory input and motor output without direct involvement of the brain.

Long-Term Potentiation (LTP)

A long-lasting increase in synaptic strength following high-frequency stimulation of a synapse.