The nervous system Flashcards

Question

Length of neurons depends on where they're found in the body

Answer 1

Sensory - short axon, cell body on the side, no dendrites Interneuron - cell body is in the middle Motor neuron - long axon, many dendrons

Answer 2

producing electrical signal leading to an action potential

Answer 3

the voltage inside the cell membrane has to go above the resting potential (-70mv) Threshold has to be reached due to voltage sensitive sodium ion channels (all or nothing principle) Induces releases of neurotransmitters across a synapse

Answer 4

re-excitability cannot occur until resting potential is restores (why there is hyper-depolarisation)

Answer 5

long distance pathways that connect the CNS to the rest of the body

Answer 6

reflexes where sensory and motor neurons induce automatic responses (hand to fire)

Answer 7

Stimuli - receptor - sensory - synapse - spinal cord - interneuron - motor - effector

Answer 8

a long projection of a nerve cell or neuron, in vertebrates, that conducts electrical impulses known as action potentials away from the nerve cell body

Answer 9

Specialised projections on neurons that bring information to the cell body

Answer 10

A rapid rise and subsequent fall in membrane potential tax occurs when a neuron send Information down an axon.

Answer 11

The membrane voltage that must be reached in an excitable cell (e.g., neuron or muscle cell) during a depolarization in order to generate an action potential. Usually-50 to-40 mV in most excitable cells

Answer 12

The gaps formed between the myelin sheath where the axons are left uncovered. This allows the generation of a fast electrical impulse along the axon.

Answer 13

made up of oligodendrocytes in the brain, rest of the body = Schwann cells

Answer 14

The body's chemical messengers released by neurons (nerve cells) to stimulate neighboring neurons or muscle or gland cells, thus allowing impulses to be passed from one cell to the next throughout the nervous system

Answer 15

Any cell of the body except sperm and egg cells.

Answer 16

Nerve cells

Answer 17

A part of the nervous system that serves to accelerate heart rate, vasoconstriction and hypertension

Answer 18

involuntary nervous system, slows heart rate, vasodilation and hypotension, increases intestinal and glandular activity, relaxes sphincter muscles

Answer 19

A traumatic brain injury that is usually caused by a blow to the head that affects brain function. Effects are usually temporary but can include headaches and problems with concentration, memory, balance and coordination.

Answer 20

An inflammation of the protective membranes covering the brain and spinal cord (meninges)

Answer 21

The loss of muscle function in part of your body