ap psych 1.1-1.3a

nature-nurture issue

are traits born or developed?

natural selection

inherited traits that help an organism survive and reproduce are passed down to future generations

evolutionary psychology

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

how are humans all alike?

behavior genetics

study of relative power and limits of genetic and environmental influence on behavior

how do humans individually differ?

environment

every nongenetic influence

heredity

genetic transfer of characteristics from parents to offspring

genes

biochemical units of heredity

parts of DNA molecules

some can be “turned on” by environmental events

genome

complete instructions for making an organism

twin and adoptions studies

studies involving identical and fraternal twins

discovered that personality is mostly affected by heredity, not environment

interactions

interplay that occurs when the effect of one factor depends on another factor

epigenetics

study of molecular mechanisms by which environments can influence genetic expression without a DNA change

self-regulating

not static, react to the environment

epigenetic marks

experiences create these

organic methyl molecules attached to a part of a DNA

turn on and off genes

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)

brain and spinal cord

peripheral nervous system (PNS)

sensory and motor neurons that connect the CNS to the rest of the body

nerves

bundled axons that form neural cables connecting the CNS to sensory organs

sensory neurons

carry messages from the body’s tissues and sensory receptors INWARD to the brain and spinal cord for processing

motor neurons

carry instructions from the CNS OUTWARD to muscles and glands

interneurons

within the brain and spinal cord

communicate internally and process information between the sensory inputs and motor ouputs

somatic nervous system

part of the PNS

controls the body’s voluntary skeletal movements

automatic nervous system

part of the PNS

controls the involuntary functions of the glands and muscles of internal organs

sympathetic nervous system

part of the PNS

arouses the body, mobilizing energy

part of fight-or-flight

parasympathetic nervous system

part of the PNS

calms the body, conserving its energy

neuron

nerve cell, basic building block of the nervous system

cell body

part of a neuron

contains the nucleus

dendrites

part of neurons

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

“listens”

axon

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

“speaks”

myelin sheath

fatty tissue layer encasing axons, allows faster transmission speed

glial cells/glia

support, nourish, and protect neurons

“worker bees” to the neuron’s “queen bee”

action potential

neural impulse

a brief electrical charge that travels down an axon

threshold

level of stimulation required to trigger a neural impulse

refractory period

a brief resting pause that occurs after a neuron has fired

all-or-none response

a neuron’s reaction of either firing with a full-strength response or not firing at all

synapse

junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

synaptic gap/cleft

the tiny gap between two neurons

neurotransmitters

chemical messengers that cross the synaptic gap

bind to receptor sites of the receiving neuron

reuptake

when neurotransmitters are reabsorbed by the sending neuron

agonist

a drug/chemical molecule that increases a neurotransmitter’s action

antagonist

a drug/chemical molecule that inhibits or blocks a neurotransmitter’s action

endocrine system

the body’s “slow” chemical communication system

a set of glands and fat tissue that secrete hormones into the bloodstream

its messages outlive neural messages, causing “endocrine hangover”

hormones

chemical messengers that are manufactured by the endocrine glands

travel through the bloodstream

influence interest in sex, food, and aggression

most influential encodrine gland

pituitary gland