APPSYCH UNIT ONE-BIOLOGY

Nature

genetics

Evolutionary Perspective

the study of the evolution of behavior and the mind, using principles of natural selection.

Natural Selection

“survival of the fittest,” organisms gaining helpful adaptations over time to help them survive better in their environment

Behavior Genetics

the study of the relative power and limits of genetic and environmental influences on behavior.

Mutations

a random error in gene replication that leads to a change.

Environment

every nongenetic influence, from prenatal nutrition to our experiences of the people and things around us.

Heredity

the genetic transfer of characteristics from parents to offspring.

Genes

the biochemical units of heredity

Genome

the complete instructions for making an organism.

Nurture

environment

Eugenics

selectively breeding humans to promote certain characteristics

Identical (Monozygotic) Twins

individuals who developed from a single fertilized egg that split in two, creating two genetically identical organisms.

Fraternal (Dizygotic) Twins

individuals who developed from separate fertilized eggs. They are genetically no closer than ordinary siblings, but they share a prenatal environment.

Interaction

the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity).

Epigenetics

“above” or “in addition to” (epi) genetics; the study of the molecular mechanisms by which environments can influence genetic expression (without a DNA change).

Nervous System

the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

Central Nervous System

brain and spinal cord

Nerves

bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sensory organs.

Autonomic Nervous System

controls self regulated actions (heart rate, breathing, etc)

Sympathetic Nervous System

arousing ( increases heart rate, breathing etc)

Peripheral Nervous System

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Somatic Nervous System

controls reflexes & muscle movement

Parasympathetic Nervous System

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Neurons

a nerve cell; the basic building block of the nervous system.

Cell Body

the part of a neuron that contains the nucleus; the cell’s life-support center.

Dendrites

a neuron’s often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body.

Axon

the segmented neuron extension that passes messages through its branches to other neurons or to muscles or glands.

Myelin sheath

a fatty tissue layer segmentally encasing the axons of some neurons; it enables vastly greater transmission speed as neural impulses hop from one node to the next (dengeneration of this leads to multiple sclerosis)

Synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap or synaptic cleft.

Glial Cells

cells in the nervous system that support, nourish, and protect neurons; they may also play a role in learning, thinking, and memory.

Reflex Arc

the pathway of neural stimulation that occurs to translate a sensation into a physical reflexive response.

Sensory Neurons

neurons that carry incoming information from the body’s tissues and sensory receptors to the brain and spinal cord (afferent)

Motor Neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands (efferent)

Interneurons

neurons within the brain and spinal cord; they communicate internally and process information between the sensory inputs and motor outputs.

Action Potential

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

All-or-Nothing Principle

a neuron’s reaction of either firing (with a full-strength response) or not firing.

Threshold

the level of stimulation required to trigger a neural impulse.

Depolarization

loss of the inside/ outside charge difference within the neuron

Reuptake

a neurotransmitter’s reabsorption by the sending neuron.

Resting Potential

The fluid outside an axon’s membrane has mostly positively charged ions; a resting axon’s fluid interior has a mostly negative charge.

Refractory period

in neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state.

Multiple Sclerosis

disease that causes diminished muscle control and sometimes impred cognition (caused by degenerating mylelin sheath)

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

Excitatory Neurotransmitters

“excite” the neuron and cause it to “fire off the message,” meaning, the message continues to be passed along to the next cell

Inhibitory Neurotransmitters

block or prevent the chemical message from being passed along any farther.

Dopamine

Influences movement, learning, attention, and emotion, oversupply linked to schizophrenia, undersupply linked to tremors and decreased mobility in Parkinson’s disease.

Acetycholine

muscle memory (action & learning), oversupply is linked to alzheimers

Glutamate

memory, oversupply linked to migraines/ seizures, undersupply linked to a decrerease in concentration

Endorphins

Neurotransmitters that influence the perception of pain or pleasure, oversupply with opioid drugs can suppress the body’s natural endorphin supply.

Serotonin

Affects mood, hunger, sleep, and arousal, undersupply linked to depression. Some drugs that raise serotonin levels are used to treat depression.

Norepinephrine

both a neurotransmitter and hormone. helps control alertness and arousal, undersupply can depress mood.

GABA

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

Substance P

Involved in pain perception and immune response, oversupply can lead to chronic pain.

Agonist

a molecule that increases a neurotransmitter’s action.

Antagonists

a molecule that inhibits or blocks a neurotransmitter’s action.

Hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.

Leptin

digestion / satisfaction

Melatonin

sleep / wake cycle

Myasthenia Gravis

when ACh (acetycholine) transmission is blocked

Endocrine System

the body’s “slow” chemical communication system; a set of glands and fat tissue that secrete hormones into the bloodstream.

Adrenaline

fight/ flight; surges during fear or excitement

Ghrelin

hunger

Oxytocin

love/ bonding

Psychoactive Drugs

a chemical substance that alters the brain, causing changes in perceptions and moods.

Substance Use Disorder

a disorder characterized by continued substance use despite significant life disruption.

Stimulants

drugs that excite neural activity and speed up body functions.

Caffeine

stimulant, increases alertness and anxiety, acts on dopamine

Cocaine

stimulant, can experience eurphoria, increases risk of heart disease, acts on acetycholine

Methamphetamines

stimulant, increases alert & energy, risk of insomnia, acts on dopamine

Ecstasy

stimulant & hallucinagen, elevates emotion, increases depression and decreases congnitive functions, acts on serotonin and dopamine

Opioids

they depress neural activity, temporarily lessening pain and anxiety.

Heroine

depressant, its euphoria and helps with pain relief, it increases depression, acts on endorphins

Addiction

continuing substance use despite consequences

Reuptake Inhibitor

stops neurotransmitters from being reabsorbed, causes the neurotransmitters to rebind over and over causing overstimulation

Depressants

drugs that reduce neural activity and slow body functions.

Barbiturates

tranquilizers, drugs that depress central nervous system activity, reducing anxiety but impairing memory and judgment.

Alcohol

depressant, causes slows brain activity that controls judgment, inhibitions and impairs memory, acts on GABA and glutamate

Hallucinogens

psychedelic (“mind-manifesting”) drugs that distort perceptions and evoke sensory images in the absence of sensory input.

Near-Death Experience

an altered state of consciousness reported after a close brush with death (such as cardiac arrest); often similar to drug-induced hallucinations.

Marijuana

hallucinogen, inreaces relaxation sensations, acts on endorphins

LSD

hallucinogen, its a visual “trip,” increases panic, acts on GABA & glutamate

Tolerance

needing a bigger dose of the drug to feel the same effect

Withdrawal

the symptoms that occur when a person ends the use of an addictive substance.

Brain Stem

connection of brain and spinal cord, responsible for automatic survival functions (breatheing, heart rate etc)

Hindbrain

consists of the medulla, pons, and cerebellum; directs essential survival functions, such as breathing, sleeping, and wakefulness, as well as coordination and balance.

Midbrain

found atop the brainstem; connects the hindbrain with the forebrain, controls some motor movement, and transmits auditory and visual information

Medulla Oblongata

the hindbrain structure that is the brainstem’s base; controls heartbeat and breathing.

Reticular Activating System (Reticular Formation)

structure inside medulla, increasing alertness, attention, and consciousness.

Forebrain

found atop the brainstem; connects the hindbrain with the forebrain, controls some motor movement, and transmits auditory and visual information

Limbic System

emotional drive

Thalamus

sensory control center except smell

Hypothalamus

5 Fs (feeding, fight, flight, fahrenheit, frolicking)

Pituitary Gland

regulates hormones

Hippocampus

stores memory of facts/ events

Amygdala

emotional control

Cerebellum

sensory input, movement/ balance & nonverbal memory

Cerebral Cortex

higher cognitive functions such as perception, memory, language, and decision-making

Split Brain

surgery that splits left and right hemispheres, usually to help with epilepsy

Broca’s Area

speaking fluently, if it is damaged, it causes broken speech

Wernicke’s Area

comprehension of language, if it is damaged the person will be able to speak fluently but it will not make sense