AP Psychology - Biological Bases of Behavior

heredity

the genetic transfer of characteristics from parents to offspring

enviornment

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

nature vs nurture

the long standing arguement over the contributions that genes and experience make to the development of traits and behaviors

evolutionary perspective

explains behavior as evolved adaptations shaped by natural selection to solve survival and reproductive problems faced by ancestors

natural selection

that the inherited traits allowing an organism to survive and reproduce in an environment (in competition with other trait variations) will be passed on to succeeding generations

eugenics

selectively breeding humans to promote certain characteristics

genes

parts of DNA that control proteins production

twins and adoption studies

studies used to compare nature vs nurture - fraternal not alike but identical are alike (identical genes matter more than identical jeans)

nervous system

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

central nervous system (CNS)

the brain and spinal cord, the body’s decision maker (hands up and down)

brain

the powerhouse that enables our humanity - our thinking, feeling, and acting

spinal cord

two-way information highway connecting the peripheral nervous system and the brain

peripheral nervous system

the sensory and motor neurons that connect the CNS to the rest of the body (jazz hands)

autonomic nervous system

division of peripheral nervous system that controls the glands and muscles of the internal organs (self regulating - heart dance)

somatic nervous system

division of peripheral nervous system that controls the body’s skeletal muscles (voluntary movements - robot dance)

parasympathetic nervous system (paradise)

the division of the autonomic nervous system that calms the body, conserving its energy (rest and digest - tree pose)

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy (fight or flight - hands to face)

neurons

the basic cellular units that receive, integrate, and transmit information by sending messages (nerve cell)

glial cells (“house keepers” or “glue”)

non-neural brains cells that provide support and protection for neurons acting; form mylon sheath and clean out dead neurons (never send messages)

reflex arc

the neural pathway controlling involuntary response to a stimulus bypassing conscious thought to prioritize homeostasis (candle burning)

sensory neurons

neurons that carry incoming information from the body’s tissues and sensory receptors to the brain and spinal cord (send up sensory info - incoming!)

motor neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands (send back motor-control info - outgoing!)

interneurons

neurons within the brain and spinal cord; they communicate internally and process information between the sensory inputs and motor outputs (inter = between nerve cells)

neural transmission

the process where neurotransmitters are released by a neuron and bind to and activate the receptors of another neuron

all-or-nothing principle

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

depolarization

the loss of the inside/outside charge difference causing the next section of axon channels to open

refractory period

a resting pause that occurs after a neuron has fired; future action potentials cannot happen without a resting period

reuptake

a neurotransmitter’s reabsorption by the sending neuron

threshold

the level of stimulation required to trigger a neural impulse

multiple sclerosis

the deterioration of myelin sheath leads to communication to the brain and muscles slowing down

myasthenia gravis

a chronic neuromuscular diseases with muscle weakness and fatigue caused by antibodies blocking nerve-to-muscle communication

neurotransmitter

chemical messengers that cross the synaptic gaps between neurons; bind to receptor sites influencing whether the neuron will generate a neural impulse

excitatory

increases the likelihood that a postsynaptic neuron will fire an action potential

inhibitory

decreases or blocks the likelihood of a neuron firing

dopamine

influences movement, learning, attention, and emotion; oversupply linked to schizophrenia and undersupply is linked to Parkinson’s

serotonin

affects mood, hunger, sleep, and arousal; undersupply linked to depression

gaba

a major inhibitory neurotransmitter; undersupply linked to seizures, tremors, and insomnia

endorphins

influence the perception of pain or pleasure; oversupply with opioid can suppress the body’s natural endorphin supply

norepinephrine

helps control alertness and arousal; undersupply can depress mood

glutamate

a major excitatory neurotransmitter, involved in memory; oversupply can overstimulate the brain

substance p

involved in pain perception and immune response; oversupply can lead to chronic pain

acetylcholine (ach)

enables muscle action, learning, and memory; with Alzheimer’s disease ach-producing neurons can deteriorate

hormones

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

adrenaline

the hormone that increases heart rate, blood pressure, and blood sugar, providing energy to power fight-or-flight

oxytocin

a hormone enabling orgasm, and, in women, labor contractions and milk flow while nursing

agonists

molecules that increase a neurotransmitter’s action

antagonists

molecules that inhibit or block a neurotransmitter’s action

axon

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

cell body

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

dendrites

the bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body

myelin

the fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed

action potential

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

endocrine system

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