nervous and endocrine system

sensory receptor

produces a stimulus

sensory neuron

gathers information from receptors

interneuron

links sensory neurons and motor neurons

motor neuron

sends electrical impulses to an effector

effector

produces a response

reflex arc

connection of neurons that result in a reflex action in response to a stimulus

dendrites

picks up an impulse

axon

transmits impulses away from the cell body to the next cell

axon terminals

brings it to another neuron first across a synapse

myelin sheath

speeds up impulse

nodes of ranvier

gap in the myelin sheath insulating the axon of a myelinated nerve cell

resting membrane potential

potential difference across the membrane in a resting neuron -70mv

polarization

lowering the membrane potential of the cell below its equalibrium value

depolarization

reducing a membrane potential to less than the resting potential of -70mV

threshold potential

the minimum change in the membrane potential required to generate an action potential -55mv

repolarization

return of a nerve to its resting potential following depolarization

synapse

junction between two neurons or between a neuron and an effector

neurotransmitters

chemical messenger secreted by neurons to carry a neural signal from one neuron to another or from a neuron to an effector

dopamine

linked with happiness and pleasure

seratonin

controls mood

endorphins

Pain and stress relief

norepinephrine

responds to dangerous situations through blood vessels

epinephrine

affects fight or flight response in the heart

spinal cord

conducts signals to and from the brain, controls reflex arc

cerebellum

controls body movement

medula oblongata

controls heart rate, blood pressure, breathing, swallowing and coughing

pons

relay centre between the neurons of the right and left halves of the cerebrum

mid brain

relays visual and auditory information

thalamus

the great relay station of the brain, relays information

hypothalamus

controls blood pressure, heart rate, body temperature and emotions

cerebrum

largest part of the brain, controls intellect, memory, consciousness and language

corpus collosum

connects right and left sides

meningez

provides protection

hypothalamus

inhitbating hormones, regulates pituitary hormones

pineal

releases melatonin,

melatonin

promotes sleepiness

pituitary

releases hGH

hGH

involved in bone and muscle growth

tSH

tells your thyriod how much hormone needs to be produced

thyroid

produces thyroxine and calcitonin

thyroxine

increases metobalic rate

calcitonin

lowers blood calcium

parathyroid

produces pth

pTH

raises blood calcium

adrenal

produces fight or flight hormones

pancreas

produces insulin and glucogon

insulin

lowers blood sugars

glucogon

raises blood sugars

ovaries

produces estrogen, female puberty, grows breast tissue

testes

produces testosterone, male puberty, produces sperm

central nervous system

network of nerves that integrates and processes information sent by nerves

brain

receives and processes sensory information, initiates responses, stores memories and generates thoughts and emotions

peripheral nervous system

carry sensory messages to the central nervous system and send information from the cns to the muscles and glands

somatic nervous system

under conscious control

hormone

chemical messanger sent to many parts of the body to produce specific effect on a target cell or organ

lipid soluble hormone

easily diffused through the cell membrane

water soluble hormone

do not passively diffuse through the cell membrane

islet of langerhams

a cluster of cells in the pancreas