BIOM 3200 Test 1 - Neuro

What are the two main divisions of the nervous system?

CNS and PNS

What is the central nervous system comprised of?

Brain and spinal cord

What is the peripheral nervous system comprised of?

Peripheral nerves and ganglia

What is the process of neurons?

Conduct electrical signals, release chemical signals, and integrate neurone activity

How do neurons conduct electrical signals?

Through action potentials

How do neurons release chemical signals?

Through neurotransmitters

How do neurons integrate neuronal activity?

Through association neurons

What are the two functions of the nervous system?

Control movement and detect external stimuli

How does the nervous system control movement?

Motor neurons

How does the nervous system detect external stimuli?

Sensory neurons

What defines a neuron?

A basic functional unit of the nervous system

What makes up a neuron?

A cell body, dendrites, and an axon

What is the purpose of dendrites?

to receive information from sensory receptors

What is the purpose of an axon?

to deliver electrical signals from the cell body to another neuron or effector organ

What neuron is used in dendrites to receive signals?

Sensory neuron

Where does integration take place?

Dendrites and cell body

Where is the action potential initiated?

Axon hillock

Where is the impulse conducted?

The axon to ending dendrites to neurotransmitters (NT)

Where are electrical impulses converted to chemical signals?

The synapse

What direction does action potential take place in?

Unidirectional

Sensory neurons (afferent) carry information from the

PNS to the CNS

Association neurons (interneurons) are found

entirely within the CNS

Motor neurons (efferent) carry information

out of the CNS

What are the two types of motor (efferent) neurons?

Somatic neurons and autonomic neurons

What do somatic neurons have control over?

Skeletal muscles (voluntary)

What do autonomic neurons have control over?

Heart, brain, etc (involuntary)

What are the two process of autonomic neruons?

Sympathetic and parasympathetic

What do sympathetic neurons do?

Speed up (Fight or Flight)

What do parasympathetic neurons do?

Slow down (Rest or Digest)

Association neurons (interneurons) carry information

neuron to neuron

What are the four different types of neurons?

Pseudopolar, bipolar, multipolar, and anaxonic

What are the most common types of neurons found in the body?

Multipolar neurons

Anaxonic neurons have no obvious

axon

What are the supporting cells of the PNS?

Schwann cells and satellite cells

What are Schwann cells?

Myelinated sheaths around the axon

What is the function of Schwann cells?

Insulate and speed up signals

What are the supporting cells of the CNS?

Oligodenrties, microglia, astrocytes, and ependymal

What do oligodendrocytes do?

Produce myelin in CNS

What di microglia do?

Pick up debris

What do astrocytes do?

Regulate the environment of neurons

What do ependymal cells do?

Help keep the shape of the brain and spinal cord

How do supporting cells of the CNS and PNS differ?

Insulation

Where are astrocytes most abundant?

Within the CNS as glial cells

What do astrocytes take up from extracellular fluid to help assist with neuron activity?

K+

What is the blood brain barrier?

A barrier creating strict control about what goes in and out of plasma into brain.

What is able to move through the blood brain barrier?

Nonpolar molecules, polar molecules, organic molecules, antibodies, immune cells,

What neuron influence the structure and function of the blood brain barrier?

Astrocytes

What are the two neurons in the efferent pathway?

Preganglionic and Postganglionic

What is the function of the preganglioninc neuron?

To cause a synapse with the second organ, but not directly innervate the effector organ

What is the function of the postganglioninc neuron?

To cause a synapse with the target tissue by going to an effector organ

What defines dual innervation?

When the same muscles or glands use both the PSNS and SNS

What are the organs without dual innervation?

Adrenal medulla, arrestor pili muscle, sweat glands in skin, and blood vessels

How are autonomic nerves classified?

By the neurotransmitters released across the synapse

What are the two neurotransmitters released across the synapse?

Achytylcholine (ACh) and Norepinephrine (NE)

What type of neuron releases ACh?

Cholinergic neurons

What type of neuron releases NE?

Adrenergic neurons

What do cholinergic neurons do?

Slow things down

What do adrenergic neurons do?

Modify things

What is synesthesia?

percieving letters or number as colours

What is chromothesia?

hear music as colours

What is synaesthesia?

coloured sounds taste sweet

What is simple diffusion?

a process of diffusion that does NOT consume energy

What is active transport?

a process of diffusion that requires metabolic energy, ATP

How does the Na+/K+ ATPase work?

Transports Na+ out of the cell and K+ into the cell

The Na+/K+ transport acts as the start of the

electrochemical gradient

What do ions do for electrochemical impulses?

Help produce the impulses that transmit information

What is the resting membrane potential voltage?

-70 mV

Where does Na+ start during resting membrane potential?

Outside

Where does K+ start during resting membrane potential?

inside

What is the primary function of nerve cells?

Receive, conduct, and transmit signals

How does depolarization work?

Positive charges flow into the cell

What is the action potential voltage?

+30mV

How does saltatory conduction work?

When one Node of ranvier is depolarized, it causes Na to rush in and travel down to the next node of ranvier. Causes the Extracellular Na from the next node of ranvier to travel to the now opened node of ranvier.

Why is saltatory conduction faster?

Myelin insulates axon, helps to maintain depolarization in cell (jumps from node of ranvier to node of ranvier)

This spread of depolarization is faster than waiting for more sodium channels to open

What is the refractory period?

a period immediately following stimulation during which a nerve or muscle is unresponsive to further stimulation. Helps action potential go in one way.

Where are neurotransmitters stored?

Synaptic vesicles

Where are neurotransmitters released?

Synapse

Where do neurotransmitters bind?

Postsynaptic receptors

What is the direction of synapse?

Presynaptic to postsynaptic

What type of matter makes up the CNS?

Gray and white matter

What is gray matter?

Mostly neuron cell bodies and nonmyelinated fibers

Where is gray matter found?

Surface layer of cortex

What is white matter?

Myelinated axons

Where is white matter found?

Under the cortex and around the nucleus

What are the meninges of the brain/spinal cord?

Dura matter, arachnid matter, and Pia matter

What is myotonia?

Delayed muscle relaxation after contraction

What is myotonia caused by?

Cl- mutation

What are the two cushions of the cerebrospinal fluid?

Outer and inner fluid cushions

What is the outer cavity of the fluid cushion?

Superior sagittal sinus (SSS)

What is the inner cavity of the fluid cushion?

Subarachnoid Space (SAS)

Where is the Superior sagittal sinus (SSS)?

Under the dura matter

Where is the Subarachnoid Space (SAS)?

Between arachnoid and Pia matter

How do we know if we have upper motor neuron damage?

Reflex is exaggerate or slightly normal

How do we know if we have lower motor neuron damage?

Reflex is diminished

What are the three primary vesicles of the brain?

Prosencephalon (forebrain)

Mesencephalon (midbrain)

Rhombencephalon (hindbrain)

What are the five secondary vesicles of the brain?

Telencephalon

Diencephalon

Mesencephalon

Mesencephalon

Myelencephalon

What are the five sections of the cerebrum?

Frontal lobe, occipital lobe, parietal lobe, temporal lobe, and insula

How is the cerebrum internally connected?

The corpus callosum

How many spinal nerve pairs are there?

31

(8 cervical)

(12 thoracic)

(5 lumbar)

(5 sacral)

(1 coccygeal)

What is the function of the frontal lobe?

Motor control