A.P. Psychology Unit 1 A Review: Biological Bases of Behavior

Heredity Influence

The genetic factors that contribute to an individual's traits and behaviors.

Evolutionary Perspective

A theoretical approach that explains behavior and development through the lens of natural selection.

Natural Selection

The process by which traits that enhance survival and reproduction become more common in successive generations.

Eugenics

A controversial movement aimed at improving the genetic quality of a population.

Twin Studies

Research methodology that compares the similarities and differences between identical and fraternal twins.

Fraternal Twins

Twins that develop from two separate eggs fertilized by two different sperm cells.

Identical Twins

Twins that develop from a single fertilized egg that splits into two embryos.

Environmental Influences

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

Genetic Predisposition

An increased likelihood of developing certain traits or behaviors based on genetic makeup.

Behavior Genetics

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

Family Studies

Research that examines the similarities and differences among family members to understand genetic and environmental influences.

Adoption Studies

Research that compares adopted individuals to their biological and adoptive families to assess the influence of genetics and environment.

Peripheral Nervous System

The part of the nervous system that includes all the nerves outside the brain and spinal cord.

Central Nervous System

The part of the nervous system that includes the brain and spinal cord.

Autonomic Nervous System

The division of the peripheral nervous system that controls involuntary bodily functions.

Sympathetic Nervous System

The part of the autonomic nervous system that prepares the body for 'fight or flight' responses.

Parasympathetic Nervous System

The part of the autonomic nervous system that promotes 'rest and digest' functions.

Somatic Nervous System

The division of the peripheral nervous system that controls voluntary movements.

Reflex Arc

The neural pathway that controls a reflex action.

Neuron Structure

The components of a neuron, including dendrites, cell body, axon, myelin sheath, and axon terminals.

Action Potential

A rapid rise and fall in voltage or membrane potential across a cellular membrane.

Resting Potential

The state of a neuron when it is not actively transmitting an impulse.

All-or-None Response

The principle that a neuron either fires completely or does not fire at all.

Neurotransmitters

Chemical messengers that transmit signals across the synapse between neurons.

Neurotransmitters

A series of algorithms that attempt to recognize underlying relationships in a set of data through a process that mimics the way the human brain operates.

Endocrine System & Pituitary Gland

The system of glands that secrete hormones into the bloodstream; the pituitary gland is often referred to as the 'master gland' because it regulates other glands.

Neuron & Myelin Sheath

A neuron is a nerve cell that transmits signals; the myelin sheath is a fatty layer that insulates the axon and speeds up signal transmission.

Glial Cells

Supportive cells in the nervous system that assist neurons by providing structural support, nutrition, and insulation.

Motor Neuron, Sensory Neuron & Interneuron

Motor neurons transmit signals to muscles; sensory neurons carry signals from sensory receptors to the central nervous system; interneurons connect neurons within the same region.

Action Potential (all-or-none)

A rapid rise and fall in voltage or membrane potential across a cellular membrane, which occurs when a neuron sends information down an axon.

Resting Potential

The state of a neuron when it is not firing, characterized by a negative charge inside the cell relative to the outside.

Threshold (excitatory vs. inhibitory)

The minimum level of stimulation required to trigger an action potential; excitatory signals increase the likelihood of firing, while inhibitory signals decrease it.

Refractory Period

The time following an action potential during which a neuron is unable to fire again.

Neurotransmitters

Chemical messengers that transmit signals across a synapse from one neuron to another.

Dopamine, Acetylcholine, Serotonin & Endorphins

Types of neurotransmitters; dopamine is involved in reward and pleasure, acetylcholine in muscle action and memory, serotonin in mood regulation, and endorphins in pain relief.

Agonists vs. Antagonists

Agonists are substances that activate receptors to produce a biological response, while antagonists block or dampen the biological response by binding to receptors.

Depressants, Stimulants, Hallucinogens

Categories of drugs; depressants reduce neural activity and slow body functions, stimulants increase neural activity and speed up body functions, and hallucinogens alter perception and mood.

Multiple Sclerosis (MS)

Destruction of the myelin sheath on neurons in the CNS and its replacement by plaques of sclerotic (hard) tissue.

Dopamine

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

GABA (gamma-aminobutyric acid)

A major inhibitory neurotransmitter. Undersupply linked to seizures, tremors, and insomnia.

Endorphins

Natural, opiate-like neurotransmitters linked to pain control and to pleasure.

Myasthenia Gravis

Autoimmune neuromuscular disorder characterized by weakness of voluntary muscles.

Ghrelin hormone

Increases hunger.

Substance P

A neurotransmitter that is involved in the transmission of pain messages to the brain.

Melatonin

Sleep hormone.

Glutamate

A major excitatory neurotransmitter; involved in memory.

Serotonin

Affects mood, hunger, sleep, and arousal.

Antagonist

A chemical or drug that binds to receptors in the brain and prevents an agonist from having a reaction.

Agonist

A molecule that increases a neurotransmitter's action.

Reuptake inhibitor drugs

Block reuptake, causing more of an NT to be available in the synapse; speed up cell firing.

Cocaine

A powerful and addictive stimulant, derived from the coca plant, producing temporarily increased alertness and euphoria.

Stimulants

Drugs (such as caffeine, nicotine, and the more powerful amphetamines, cocaine, and Ecstasy) that excite neural activity and speed up body functions.

Depressants

Drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions.

Tolerance

The diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drug's effect.

Efferent neurons

Nerve cells that conduct impulses away from the central nervous system.

Interneurons

Neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs.

Glial cells

Cells in the nervous system that support, nourish, and protect neurons.

Norepinephrine

Excitatory or inhibitory; role in regulating mood.

Oxytocin

A hormone released by the posterior pituitary that stimulates uterine contractions during childbirth and milk ejection during breastfeeding.

Serotonin

A neurotransmitter that contributes to feelings of well-being and happiness, playing a crucial role in mood regulation.