things i need to study neuroglia, etc.

cluster of cell bodies

ganglion

somatic motor neurons take impulse to

skeletal muscles

visceral motor neurons take impulse to

cardiac and smooth muscle

form lining of spaces within the brain (& circulate cerebrospinal fluid)

ependymal cells

mobile phagocytes, protect brain from pathogens

microglia

maintain the blood-brain barrier (also help with physical support of neurons)

astrocytes

form myelin sheath, speeds up impulse transmission

oligodendrocytes

Schwann cells form the myelin sheath to speed up impulses, guides the growth of a new axon, but also helps with repair of damaged axons known as: (two words)

Wallerian Degeneration

A potential is a:

difference in electrical charge on 2 sids of a membrane

most K+ is (inside/outside the cell)

Potassium is inside (cytoplasm)

Na+ is inside or outside the cell

Sodium is outside (extracellular fluid)

a chemically gated channel is opened by:

the binding of a neurotransmitter

a voltage gated channel is opened when:

the electrical charge changes

a mechanically gated channel is opened by:

physical pressure

a graded potential is a local change in the transmembrane potential where a few channels open and a small amount of ions pass into the cell

yes

example of a graded potential

• A presynaptic neuron releases a neurotransmitter.

• The neurotransmitter binds to a chemically gated channel on the dendrites of the next neuron.

• The channel opens, allowing Na⁺ (sodium) to enter the neuron.

• The positive Na⁺ makes the inside of the neuron less negative.

• This change in charge creates a graded potential.

• If the signal is strong enough to reach threshold, it triggers an action potential. If not, the signal fades away

• 
  

• Easy way to remember: presynaptic neuron releases neurotransmitter, then channel opens and Na⁺ enters neuron which causes the inside to become less negative → if strong enough, an action potential happens!

example of action potential

Example of an Action Potential:

1. A neurotransmitter opens chemically gated channels, creating a graded potential.

2. Na⁺ (sodium) enters the neuron, making the inside less negative.

3. The neuron reaches threshold (about −60 mV).

4. Voltage-gated Na⁺ channels open, allowing lots of Na⁺ to enter.

5. The charge rises to about +30 mV. This is called depolarization.

6. Na⁺ channels close, and voltage-gated K⁺ channels open, allowing K⁺ (potassium) to leave. The charge drops. This is called repolarization.

7. Too much K⁺ leaves, making the inside briefly more negative than its resting state. This is called hyperpolarization.

8. The neuron returns to its resting potential (about −70 mV) with help from leak channels and the sodium-potassium pump.

Easy way to remember:

• Na⁺ enters → Depolarization (less negative, so charge goes up).

• K⁺ leaves → Repolarization (charge goes down).

• Too much K⁺ leaves → Hyperpolarization.

• Returns to −70 mV → Resting state.

neurons cannot respond to a 2nd stimulus during an action potential. this is called the:

refractory period

will only respond to a stronger stimulus

relative

will not respond at all

absolute

continuous conduction (is it mylinated or unmylinated axons, slower or faster, and because the action potential has to move….

unmyelinated axons, slower,, because the action potntial has to mvoe continuously down entire axon

saltatory conduction what type of axons, faster or slower, because the action potential must only be generated at each what?

myelinated, faster, only generated at each node (it essential jumps down the axon)

A (BLANK) is a gap between schwann cells in the myelin sheath

node

merkel cells are found in what layer of the skin and what are they?

strautm basale, touch receptors

what are the 3 meninges?

1.) dura mater (outer layer)

2.) arachnoid mater (middle layer)

3.) pia mater (inner layer)

the specific area of the body that is monitored by a pair of spinal nerves is called the

dermatome

this layer of connective tissue of the spinal nerve (wraps around the entire nerve)

epineurium

this layer of connective tissue of the spinal nerve (surrounds bundles of axons called fascicles)

perineurium

this layer of connective tissue of a spinal nerve (surrounds each individual axon)

endoneurium

The cervical plexus contains what nerve and what is its function?

phrenic nerve

stimulates the diaphragm

The brachial plexus contains what nerve and is known as the

ulnar nerve

funny bone

the lumbar plexus contains what nerve and is a major nerve in the what

femoral nerve

thigh

the sacral plexus contains what nerve and is the largest and longest nerve

sciatic nerve

the 4 classifications of reflexex includes: development, complexity, processing site, and (3 words)

nature of response (somatic reflexes = involuntary control of skeletal muscles) and (visceral reflexes control of internal organs)

what is the reflex where stepping on a sharp object and it causes you to pull your foot up?

crossed extensor reflex

a reflex is a

predictable, rapid response

lines of cleavage are parallel bonds of (what and what)

collagen & elastic fibers