2. Nerve Cells

Question 1

What is a Neuron/nerve cell?

Answer 1

• Functional unit of the Nervous system that regulates body processes
• Respods to & releases chemicals
• Directs electrochemical signals

Question 2

What is a nerve?

Answer 2

• A bundeled pathway of neurons

Question 3

What is a gial cell?

Answer 3

Cell that defends against infection

Question 4

What are the Parts of the Neuron?

Answer 4

1 Dentrites:
* Receives messages from neurons or sensory receptors

2 Cell Body:
* Where site reactions occur

3 Axon:
* sends messages through nerve impulses

4 Schwann cells:
* Makes Myelin

5 Myelin Sheath:
* Layer of lipids that increase the speed of signals

6 Nodes of Ranvier:
* Gaps in Myelin sheath where ions come in and out

7 Axon Terminal:
* Branches at the end of the axon where messages are sent to neuron or an effector.

Question 5

What are the Types of Neurons?

Answer 5

1. Sensory afferent: Carry message
2. Motor efferent: send info to affectors
3. Interneurons: Coordinate response betweeen the first two, in CNS

Question 6

What is the steps of the Neural Pathway/ Reflex Arc?

Answer 6

1. Stimulus
2. Ganglia
3. Info’s sent
4. Message gets to CNS where they link ingoing and outgoing messages
5. Motor neurons
6. Effectors produce a response

Question 7

How neural signals are carried: Neurotransmitters

What is a Neurotransmitter?

Examples: acctycholine

Answer 7

• Chemical messengers to carry a signal between either neurons or an effector

They are chemical messengers secreted by neurons

Question 8

How neural signals are carried: Neurotransmitters

What is Synapse?

Answer 8

• Where two nerve cells meet or nerve cell meets an effector

Question 9

How neural signals are carried: Neurotransmitters

What is the Synaptic Vesicles?

Answer 9

• Membrane-bound sac carrying neurotransmitters

Question 10

How neural signals are carried: Neurotransmitters

What is Synaptic Cleft?

Answer 10

• Space between the presynaptic neuron & postsynaptic neuron or effector.

Question 11

How neural signals are carried: Neurotransmitters

How are Neural Signals carried?

Answer 11

1. Neurotransmitters travel across synaptic cleft in synaptic vesicles.
2. They bind to receptors in postsynaptic dentrite
3. When there’s enough signal, the nerve impulse will travel after initating from action potential