Nervous System and Neurotransmitters: Functions, Reflex Arc, and Drug Effects

What is the main function of the Nervous System?

Communication to the brain

What does CNS stand for?

Central Nervous System

What does PNS stand for?

Peripheral Nervous System

What are the two main components of the Peripheral Nervous System?

Sensory and motor systems

What is a neuron?

A nerve cell

What is the role of dendrites in a neuron?

They take in information and pass it to the nerve cell body.

What is the action potential?

An electrical signal that travels down the axon of a neuron.

What is the gap between the axon of one neuron and the dendrite of another called?

Synapse

What are neurotransmitters?

Chemicals that carry signals across the synapse between neurons.

Name two examples of neurotransmitters.

Epinephrine and serotonin and dophomine

What is the function of the myelin sheath?

To coat the axon and help transmit signals faster.

What is the reflex arc?

A neural pathway that controls a reflex action.

What are the three types of neurons involved in a reflex arc?

Sensory neuron, interneuron, and motor neuron.

What does adrenaline (epinephrine) do in the body?

Increases heart rate, blood pressure, breath rate, and alertness.

What is the effect of noradrenaline (norepinephrine)?

It reverses the effects of adrenaline.

What are stimulants?

Drugs that mimic the effects of adrenaline, such as nicotine and amphetamines.

What are depressants?

Drugs that mimic the effects of noradrenaline, such as alcohol and Valium.

What is the 'fight or flight' response?

A physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival.

What is the role of endorphins?

Natural painkillers in the body that can create a 'runner's high.'

How does cocaine affect neurotransmitters?

It prevents the re-uptake of serotonin, norepinephrine, and dopamine, keeping them in the synapse longer.

What is the function of the thalamus?

It acts as a regulatory center, deciding what sensory input to pass on to the cortex.

What does the hypothalamus regulate?

Hunger, thirst, body temperature, hormones, and circadian rhythms.

What are the five senses?

Vision, hearing, smell, taste, and touch.

What is the kinesthetic sense?

The sense of body position and movement.

What is the speed of transmission for a nerve signal?

About 5 m/s, but can increase to 150 m/s with myelin sheath.

What ions build charges to be restored using sodium and potassioum pumps

Sodium and potassium ions

speed of transmission

abour 5/s but with thr mylin sheth it increases to 150m/s

takes arounf 7 milliseconds for a nerve signals to travel from your spinal cord to your toes

intensity of stimulus and how to know when to transmit signals

action potential, is all or none

# of neron the fire

frequency of firing

Brian structure

axon structure (nerve)

cerebrum

Area of the brain responsible for all voluntary activities of the body or cerebral cortex. (outer)

cerebellum

A large structure of the hindbrain that controls fine motor skills. (walking, sports)

brian stem (medulla)

responsible for basic functions (breathing and heart rate)

Thalamus

regulatory center, depends on what input to pass to the cortex (traffic noise, and baby cry)

Hypothalamous

a neural structure lying below the thalamus. directs (eating, drinking, body temperature), governs the endocrine system via pituitary, linked to emotion and "reward center"

(body clock)

vison

photoreceptors on the retina--> optic nerve; roda and cones

hearing

3 bones: malleus, incus, and stapes = hammer anvil and stirrup (virate and pass signal to sensitive hair woth cochlea)

olfactory

relating to the sense of smell

millions of small

accociated with memeory

taste

the sensation of flavor perceived in the mouth and throat on contact with a substance. (taste buds on the roof the the mouth) (savory amino acids)

toach

pressure and pain + temp

vestibular

sense of balance (fluid in inner ear--> gravity)