Nerons

Question 1

What?

Answer 1

Nerve cells that send messages all over your body to allow you to breath, to talk, to eat, to think, etc…
Billions of neurons and many types
3 main ones are Sensory, motor and interneuron

Question 2

Sensory

Answer 2

Carry sensory information from receptors to CNS to be processed
Nucleus off the axon - VI
ONLY ONE WITH RECEPTORS
MUST READ RECEPTORS FIRST

Question 3

Interneuron

Answer 3

Form links between other neurons, only occur within brain and spinal cord
Nucleus is in between cell body and dendrite - VI THERE IS NO APPARENT AXON

Question 4

Motor neuron

Answer 4

Carry impulses from CNS system using PNS to effectors (which are generally muscles or gland) and make them work
Nucleus is at the end of the neuron within the DENDRITE AT THE TOP- VI

Question 5

Dendrite

Answer 5

Branched extensions of a neuron which receive stimuli from other neurons or receptors

Question 6

Cell body

Answer 6

Mass of cytoplasm with contained nucleus (only for sensory)
Controls the nucleus and controls cell activity for neuron

Question 7

Axon

Answer 7

Transmits electrical impulses

Question 8

Myelin/ myelin sheath

Answer 8

Insualtes (prevents loss of impulse) and increases speed of electrical impulses (protects axon)
Protects from - toxins, physical damage and sometimes disease

Question 9

Nucleus

Answer 9

Controls cell activity in neuron

Question 10

Axon terminals

Answer 10

Release chemical messenger/ neurotransmitters to next dendrite/ neuron over synaptic gap

Question 11

A nerve consists of

Answer 11

Bundle of motor and sensory neurons
Blood vessels and tissue

Question 12

From stimuli to response

Answer 12

Stimuli (Thing affecting senses e.g. fragrance)
Receptor (5 senses/body parts - inside)
Sensory neuron
PNS
Spinal cord
Interneuron
Brain (CONTROL CENTRE)
CNS
Motor neuron
PNS
Effector (muscles and glands)
Response

Question 13

Transmission

Answer 13

Transmission of a signal between neurons is generally carried by a chemical called a neurotransmitter.

Question 14

Process

Answer 14

A neuron gets an electrical signal
Signal reaches end of neuron, but there’s a gap, the synapse or synaptic gap
The neuron releases special chemicals called neurotransmitters across gap to get across
The next neuron has receptors specifically fit for the type of neurotransmitter to catch chemicals - proteins
Once landed, the next neuron starts the process again

Question 15

Types

Answer 15

Adrenaline - fight or flight neurotransmitter
Noradrenaline - Concentration neurotransmitter
Serotonin - Mood neurotransmitter

Question 16

Affected by agonists (mimic)

Answer 16

Fit into receptors and trigger the same response yet heightened
Caffeine adrenaline, dopamine and it increases alertness and mental focus

Effects - Jitters, anxiety and difficulty sleeping

Question 17

Antagonists (Block)

Answer 17

Fit into receptors but block neurotransmitters from having usual effect
Paracetamol - Blocks chemical messengers to brain that you have pain

NOTE - agonists + antagonists = less activation, not no activation

Question 18

Less myelin

Answer 18

MS disease
Nerve impulses slow or even stop This can cause neurological symptoms such as trouble walking or seeing, or changes in bladder function

Question 19

Small transmission process

Answer 19

Dendrite axon synapse dendrite axon synapse dendrite…