Unit One Flashcards
spinal cord
long bundle of neurons that carries information to and away from the brain; helps control pain response
peripheral nervous system
made of the nerves and neurons not contained in the brain and spinal cord
allows the brain and spinal cord to communicate with the sensory systems and to control the muscles and glands of the body
divided into somatic and autonomic nervous systems
somatic nervous system
controls the voluntary muscles of the body
involves the sensory pathway and the motor pathway
autonomic nervous system
controls automatic functions of the body (organs, glands, involuntary muscles)
has sympathetic and parasympathetic divisions
sensory pathway
sensory neurons carrying information to spinal cord and/or brain
motor pathway
nerves that carry information to voluntary skeletal muscles
sympathetic division
fight or flight functions—reacts to stressful events and bodily arousal
parasympathetic division
eat drink and rest functions—restores body to normal functioning after arousal and is responsible for day-to-day functioning of glands and organs
endocrine glands
secrete chemicals called hormones into bloodstream
affect behavior and emotions by influencing the activity of the brain and by controlling muscles and organs such as the heart, pancreas, and sex organs
spinal cord reflexes
involve sensory neurons, interneurons, and motor neurons
enable fast, often lifesaving, actions that do not require conscious thought
pancreas
controls level of blood sugar in body by secreting insulin and glucagon
diabetes vs hypoglycemia
too little insulin is diabetes
too much insulin is hypoglycemia (low blood sugar, hungry)
gonads
secrete hormones that regulate sexual behavior and reproduction
ovaries in female and testes in male
ovaries
female gonads
testes
male gonads
adrenal glands
everyone has two, on top of each kidney
has two sections
stress stuff
adrenal medulla
releases epinephrine and norepinephrine when people are under stress
aids in sympathetic arousal
adrenal cortex
produces corticoids
corticoids
adrenal cortex produces over 30 different hormones called corticoids
also called steroids
regulate salt intake, help initiate and control stress reactions, and provide source of sex hormones
cortisol
most important adrenal hormone
released when body experiences physical and psychological stress
important in release of glucose during stress (gives brain energy) and release of fatty acids (gives muscles energy)
neuroscience
the field of study that deals with the structure of the brain and components of the nervous system
neuron
specialized cell in nervous system
send and receive messages within that system
have specialized components
have an electrical charge at rest (resting potential)
are affected by neurotransmitters, chemicals that have an effect on neurons
are separated by a gap called the synapse, when nerve impulse reaches axon terminals, neurotransmitter is released into synaptic space
glial cells
provide physical and metabolic support to neurons
communicate with other cells
specific types have stem cell like properties
myelin
insulates axons and speeds up transmission of neural message
oligodencrocytes
produce myelin in the central nervous system
schwann cells
produce myelin in the peripheral nervous system
how does a neuron work
neuron at rest negatively charged inside and positively charged outside
action potential occurs when positive sodium ions enter into cell, causing a reversal of the electrical charge from negative to positive
as action potential moves down axon toward axons terminals, cell areas behind action potential return to resting state of a negative charge as positive sodium ion are pumped to outside of cell, positive potassium ions rapidly leave
all or none fashion
neurons are either firing at full strength or not firing at all
synaptic vesicles
sac like structures in presynaptic terminal
neurotransmitters
inside a neuron, transmit messages
synapse
fluid filled space between axon terminal and dendrite of another neuron
synaptic gap
fluid filled space between axon terminal and dendrite of another neuron
receptor sites
proteins that allow only particular molecules of a certain shape to fit into it
excitatory synapses
neurotransmitters that turn cells on
inhibitory synapses
neurotransmitters that turn cells off
ACh
first neurotransmitter identified
acetylcholine
at synapses between neurons and muscle cells
stimulates skeletal muscles to contract, slows contractions in heart muscle
curare
a drug used by south american indians on their blow darts, antagonist for ACh
antagonist
a chemical substance that blocks or reduces the effects of a neurotransmitter
agonist
a chemical substance that mimics or enhances the effects of a neurotransmitter
dopamine
neurotransmitter found in brain
can have different effects ex parkinson’s and schizophrenia
seratonin
neurotransmitter in lower brain
excitatory or inhibitory effect
associated with sleep, mood, anxiety, and appetite
glutamate
nervous system’s major excitatory neurotransmitter
role in learning and memory
don’t want too much
gamma-aminobutyric acid
neurotransmitter
GABA
most common neurotransmitter producing inhibition in the brain
alcohol is agonist
neuropeptides
can serve as neurotransmitters, hormones, or influence the action of other neurotransmitters
endorphins
pain controlling chemicals in the body
reuptake
neurotransmitters end up back in synaptic vesicles through reuptake, where chemicals are sucked back up into vesicles
enzymatic degradation
enzyme specifically designed to break apart ACh clears the synaptic gap very quickly
central nervous system
brain and spinal cord
controls life sustaining functions of body as well as thought, emotion, and behavior
afferent (sensory) neurons
carry messages from senses to spinal cord
efferent (motor) neurons
carry messages from spinal cord to muscles and glands
interneurons
connect afferent neurons to motor neurons
make up inside of spinal cord and much of brain itself
reflex arc
afferent neuron sends pain message up to spinal column where it enters into central area of spinal cord
interneuron in that central area receives message and sends response along efferent neuron
doesn’t need to go to brain
neuroplasticity
the ability to constantly change both the structure and function of many cells in the brain in response to experience and even trauma
brain has a great deal
stem cells
can become any cell in the body
can repair damaged or diseased tissue
peripheral nervous system
made of the nerves and neurons not contained in the brain and spinal cord
allows the brain and spinal cord to communicate with the sensory systems and to control the muscles and glands of the body
divided into somatic and autonomic nervous systems
hormones
chemicals secreted by endocrine glands
affect behavior and emotions by stimulating muscles, organs, or other glands
pituitary gland
in brain below hypothalamus
master gland
controls or influences all of other endocrine glands
controls pregnancy, water levels, activity of other glands, important part of feedback system
oxytocin
hormone that controls aspects of pregnancy
involved in reproduction and parental behavior
stimulates contractions of the uterus in childbirth, used to speed up labor and delivery, responsible for milk letdown reflex
milk letdown reflex
contraction of mammary gland cells to release milk for nursing infant
vasopressin
hormone that controls levels of water in our body
helps body conserve water
growth hormone
controls and regulates the increase in size as children grow from infancy to adulthood
pineal gland
in brain, role in biological rhythms
secretes melatonin
melatonin
pineal gland secretes this
helps track day length and seasons
influences seasonal behaviors and sleep-wake cycle
thyroid gland
in neck
secretes hormones that regulate growth and metabolism
secretes thyroxin (regulates metabolism)
psychology
the scientific study of behavior and mental processes