Unit 1 (AP) 1.1 thru 1.3 Flashcards
epigenetics
the study of environmental factors changing the gene expression without a DNA change.
monozygotic
similarities due to what?
identical twins: similarities due to nature (genetics)
dizygotic
similarities due to what?
fraternal twins: similarities due to nurture (environment)
heritability
definition?
examples?
the amount of variation in individuals attributed to genetics. examples: height, intelligence
twin studies; what type of research study is it (usually)?
longitudinal case studies
peripheral nervous system
nerves from all other body parts (limbs, torso…)
central nervous system
brain + spinal cord
somatic nervous system
controls voluntary body movements(muscles)
autonomic nervous system
controls involuntary body movements (heart rate, blood pressure)
sympathetic nervous system
“fight-or-flight’ response, increasing heart rate, dilates pupils, inhibits digestion and saliva production, stimulates epinephrine release
parasympathetic nervous system
“rest” after stressful events or just resting mode: decreasing heart rate, constricts pupils, digestion and saliva production stimulated, inhibits adrenaline (epinephrine) release
sensory (afferent) neurons
carry info from the body to the brain: send afferent signals
- different for each different sense
- respond to non chemical stimulation
“afferent signals arrive @ the brain”
interneurons
neurons within the brain and spinal cord which take the messages and send them elsewhere in the brain OR to motor(efferent)neurons.
motor (efferent) neurons
neurons that carry info from the brain to the body:
- connected to all of our muscles
- receive efferent signals
EFFERENT signals EXIT the brain.
glia cells
assist neurons but also communicate on their own with chemical signals (which is why they don’t show up on EEG’s)
glia # 10x more than neurons
dendrites
rootlike parts of a neuron that stretches out from the cell. They grow to make connections with other neurons through their axon terminals and neurotransmitters.
soma
contains the nucleus and other parts of the neuron.
axon
carries electrical messages from the soma to the axon terminals where the signals are fired via neurotransmitters.
myelin sheath
fatty layer around the axon that helps with neural transmission. Absence/ deterioration of myelin sheath causes multiple sclerosis.
terminal buttons
sites at the axon terminal where the neurotransmitters are released via vesicles.
axon terminal
releases neurotransmitters, end of the neuron
synapse
gaps between the terminal button of one neuron and the dendrite of the next neuron
progression of neural firing:
DSATs:
Dendrite-Soma-Axon-Terminal-synapse
resting potential
nonactive neuron, polarized (negatively charged) (-70mV) on the inside, positive charge on the outside.
action potential
when the neuron gets positive ions and fires an electrical signal down the axon (change in charge)
excitatory (neurotransmitters)
make the receiving neuron more likely to fire
inhibitory(neurotransmitters)
make the receiving neuron less likely to fire
firing threshold
amount of neurotransmitters needed for a neuron to fire
all or none principle
if a neuron gets enough neurotransmitters, it will fire completely, and in the same intensity every time. If it DOES NOT get enough neurotransmitters it DOES NOT fire at all.
refractory period
a brief moment where a neuron can’t fire
reuptake
after sending the neurotransmitters, the sending neuron recollects the neurotransmitters from the receptor sites of the dendrites (of the receiving neuron) and reuses them.
depolarization
the process of neural firing, called like this because the neuron fires due to the change in charge, going from negative to positive, thus going from polarized to depolarized.
neurotransmitter
chemical signals that trigger neural firing
glutamate
most abundant excitatory neurotransmitter, involved in learning and memory
GABA
important inhibitory neurotransmitter, linked to anxiety disorders, internalizes when having seizures and can cause sleep problems (excess or deficit)
acetylcholine (ACh)
neurotransmitter involved in motor functions and learning.
dopamine
associated with pleasure and rewarding activities, also motor movement and alertness + low levels associated with Parkinson’s and high levels associated with schizophrenia
serotonin
involved in mood, appetite, sleep and dreams + low levels associated with depression
norepinephrine
provides energy and alertness, heavily involved in sleep + low levels associated with depression.
epinephrine
primary chemical in “fight-or-flight” response, boost of energy
endorphine
natural morphine of the body, ends pain, associated with addiction.
agonist
chemical that increases neurotransmitter action.
direct agonist
+example?
chemical that mimics certain neurotransmitters and binds with the next neuron’s dendrites.
example: heroin
nicotine
black widow venom
indirect agonist+
example?
chemical that blocks the reuptake process and floods the synapse with the neurotransmitter.
(reuptake inhibitors)
example:prozac
cocaine
antagonist
substance that blocks the receptors of the next neuron, not allowing the neurotransmitters to lock into the dendrites.
examples: botox - antagonist for ACh
thorazine - antagonist for dopamine (early schizophrenia drug)
depressant
example:?
they slow down the autonomic and central nervous systems, inhibit reasonable judgment and thinking, depress the brain.
example: alcohol: agonist for GABA(slow down neurotransmitter)
antianxiety meds
stimulant
example:?
they activate the sympathetic nervous system and arouse the autonomic NS. Can cause tolerance + withdrawal symptoms like other drugs.
examples: caffeine (antagonist for adenosine)
cocaine (agonist for dopamine)
opiates
they are mainly agonists for endorphin. Relieve pain and uplift mood
example: heroin
hallucinogens
they cause sensory and perceptual disruptions
example: LSD, marijuana(THC)
can cause reverse tolerance when taken a second dose if there’s still some amount left in body
tolerance
when taken psychoactive drugs one builds tolerance and therefore needs increasing doses to experience the same level of effects.
