Nerves

I believe it's Na+

the nerve of the ear sends messages to the brain to allow you to hear.

The spinal accessory nerve, or cranial nerve XI (eleven), is a purely motor nerve which innervates the trapezius and sternocleidomastoid muscles. The sternocleidomastoid muscles are used to turn the head.

The Accessory nerve also provides somatic motor fibers to muscles of the soft palate, pharynx, and larynx (spinal and medullary fibers respectively.)

The most important one is the brain. A surgeon can do surgery on the brain while the patient is awake.

structurally they are very similar with the only real difference being that the myelinated (M) nerve (neurone) has schwann cells on its axon surface, but functionally they are very different as the M transmitts nerve impulses alot faster than the non-myelinated(NM) as it has nodes ranvier that allow the impulse to jump from gap to gap between schwann cells and so sppeding the rate at which it can depolarise the membrane to allow transmittion of the impulse, i could go on alot more but i wont :) hope this helps

yours scincerly a uni student trying to look smart ;)

i got to OXFORD (brookes) ...

the tip of the penis on a man, and the clitoris on a woman have the most sensitive nerve endings.

Damage to a single spinal nerve will not completely paralyze a limb.

A (proto)typical neuron contains three parts: a cell body, an axon, and a tree of dendrites. The cell body is also called the soma, which comes from the Latin for "body". Among many important tasks, the cell body houses the nucleus and most of the other cytoplasmic organelles. For this reason, yet another name for the cell body is the perikaryon, which comes from the Greek for "around the nut", where "nut" refers to the nucleus; thus the cell body is the thing that surrounds the nucleus.
The nucleus is present in the cyton, or main body of the neuron.
Soma or the cell body

The sodium ion concentration is higher on the outside of the cell and potassium ion concentration is higher on the inside of the cell

jj

autonomic

Nerve root effacement refers to nerve root compression. This is an issue where the root of the nerve is compressed into the spine before exiting it, which can cause some painful back symptoms.

The chemical used to send messages across synapses is acetylcholine or ACh.

* dura

* the arachnoid * the pia mater

No sponges lack organized multicellular organs, such as nerves and muscles.

The vagal nerve stimulator has two parts: an electrode that wraps around the left vagus nerve in the neck; and a pulse generator, which is implanted under the skin below the collarbone. The two parts are connected by a wire.

neurotransmitter carries the nerve impulses from neuron to neuron across a synapse

cranial nerves arise from the brain inside the cranial cavity.

neuromuscular junction

no, they transport vigear to the brain through blood.

It varies:

In the somatic system (skeletal muscle) and parasympathetic branch of the autonomous nervous system (smooth & cardiac muscle) it is usually acetylcholine.

In the sympathetic branch of the autonomous nervous system (smooth & cardiac muscle) it is usually norepinephrine (also called noradrenaline).

There are exceptions, but this is the general rule.

Via chemical messangers that cross the synapse.

Not minerals, it is ions. Calcium ions and sodium ions.

there's the axon (the nerve) the electrical impulse goes down that and covering the axon is the myelin sheath, otherwise known as a fatty sheath which insulates and helps make the electrical impulse go faster. In between each myelin sheath there are synapses (gaps between each one) and the impulse has to cross the gap so neurotransmitters are released which bind to receptors on the other side creating another electrical impulse which makes it travel even faster.

spinal nerve