Unit review video 3 neuro system

Question 1

What is the function of the nervous system?

Answer 1

To Provide commutation from the external environment to the internal environment. (Control center of the body)

Question 2

Explain the structural divisions of the nervous system.

Answer 2

Central nervous system
- Brain
- Spinal Cord

Peripheral Nervous system
- Nerves
- Ganglia

Question 3

Explain the functional divisions of the nervous system.

Answer 3

Central nervous system
- Integration (receives information and makes decisions with information)

Peripheral Nervous system
- Sensory: Recieve information
- Motor: Send information

The motor is divided into somatic and autonomic.

Question 4

The function of Somatic and Autonomic. (PNS Motor)

Answer 4

Somatic
- Send signals to skeletal muscle ( voluntary control)

Autonomic
- Send signals to cardiac, smooth muscle, and glands.

Question 5

The function of Visceral and somatic.
(CNS)

Answer 5

Visceral
- Send a message to deep organs from inside

somatic
- send message From outside to deep organ.

Question 6

Neuroglia in the Central Nervous system.

Answer 6

• Astrocytes: Protect
• Microglia: Immune cells (phagocytes)
• ependymal cells: Move Cerebral spinal fluid
• Oligodendrocytes: Form the myelin Sheath

Question 7

Neuroglia in the Peripheral nervous system.

Answer 7

• Schwann cells: Create Myelin sheath
• Satellite: Protect cell bodies of neurons

Question 8

What is the function of Neuroglial cells?

Answer 8

To support and protect neurons.

Question 9

Neuron parts and functions.

Answer 9

• Dendrites: Recieve messages ( more dendrites the more you receive)
• Cell body: Control center of neuron
• Axon: Send messages

Question 10

What is the difference between a nerve and a tract?

Answer 10

Nerve: Bundle of axons in the Peripheral nervous system

Tract: Bundle of axons in Central nervous system.

Question 11

Where are the Nucelous and Ganglia found?

Answer 11

Nucleus: found in Central nervous system

Ganglia: Perphial nervous system (cell body)

Question 12

Explain the importance of the myelin sheath and describe how it is formed in the central and peripheral nervous systems

Answer 12

Central nervous system
- Oligodendrocytes: Wrap around the axon, leaving spaces called nodes of Ranvier

Peripheral nervous system
-Schwann cells: Wrap around the axon, leaving spaces called nodes of Ranvier

These are insulated, leading to the speed of transmission.

Question 13

Characteristic of a neuron.

Answer 13

• Send and receive
• Electrical
• Excitable
• Long-lived (100 years +)
• Amitotic (Dont divide)

Question 14

Define resting membrane potential and describe its electrochemical basis.

Answer 14

Resting membrane potential
- Positive on the outside
- Negative on inside
- (-70) on inside
- sodium-potassium pump 3 Na+ outside K+ inside
- K+ is leaking out through leak channels
- nothing happens

Question 15

Compare and contrast graded potentials and action potentials.

Answer 15

Graded potentials: Graded potentials are triggered by various stimuli, such as neurotransmitters binding to receptors, mechanical stimulation, or changes in ion concentrations.

Action potentials are triggered when the membrane potential reaches a certain threshold, typically around -55 to -50 millivolts. This threshold must be reached to initiate an action potential.

Question 16

Define absolute and relative refractory periods.

Answer 16

The absolute refractory period ensures that action potentials are discrete events and prevents the neuron from generating overlapping signals

relative refractory period temporarily reduces the neuron’s excitability, requiring a stronger stimulus to initiate another action potential.

Question 17

Types of graded membrane potential

Answer 17

EPSP: Deporazation positive (Na+) trigger action potiental

IPSP: Hyperpolerize negative (k+)

Question 18

Where does action potential begin?

Answer 18

Axon Hillock

Question 19

Define saltatory conduction and contrast it to conduction along unmyelinated fibers

Answer 19

Saltatory conduction: More efficient because no ions leak out. It’s quicker. Myelin sheath is hydrophobic, which keeps ions moving faster through voltage-gated channels.

Unmyelinated Ions can leak out, which leads to slower.

Question 20

What channels are on the cell body?

Answer 20

Ligand-gated channels

Question 21

What channels are on the axon?

Answer 21

Voltage-gated channels

Question 22

What is Snyapes

Answer 22

The space between a neuron and something else. Communication area between another neuron, muscle, or gland

Question 23

Distinguish between electrical and chemical synapses by
structure and by the way they transmit information

Answer 23

Chemical synapses are none fused synapses( slower)

Electrical synapses Are fused faster. Communicated through gap junctions.

Question 24

Distinguish between excitatory and inhibitory postsynaptic potentials.

Answer 24

EPSP: ligand-gated channels open sodium rushin, making the membrane more positive to -55mV. Depolarization. ( start action potienal)

IPSP: K+ channel opens or chlorine, and K+ rushes out, making it more negative -80 mV. Hyperpolarization. (stop action potential)

Question 25

Describe how synaptic events are integrated and modified.

Answer 25

synaptic events are integrated and modified through spatial and temporal summation of excitatory and inhibitory inputs, determining whether the postsynaptic neuron will fire an action potential.

Question 26

Define neurotransmitters and name several classes of neurotransmitters.

Answer 26

A neurotransmitter is a chemical substance that transmits signals across a synapse, which is the junction between neurons or between a neuron and an effector cell (such as a muscle or gland cell)

1. Amino Acids
2. Monoamines
3. Acetylcholine
4. Neuropeptides
5. Gasotransmitters
6. Purines

Question 27

Describe common patterns of neuronal organization and processing.

Answer 27

CNS neurons are organized into several types of neuronal pools, each with distinguishing patterns of synaptic connections called circuits.

The four basic circuit types are diverging, converging, reverberating, and parallel after-discharge.