Synaptic Activity Cue Cards

Question 1

What are synapses?

Answer 1

The places where neurons connect and communicate with each other, they are how neural impulses get transferred cell to cell.

Question 2

What are the two types of synapses?

Answer 2

Chemical Synapse and Electrical Synapse.

Question 3

How does an electrical synapse work?

Answer 3

The transfer of ions through connexon channels in a gap junction

Question 4

What is different about a electrical synapse from a chemical synapse?

Answer 4

There is direct contact between the presynaptic neuron and the post synaptic neuron, and the electrical synapse does not involve neurotransmitters

Question 5

How does a chemical synapse work?

Answer 5

Neurotransmitters are getting released into the synaptic cleft where they will go through ion channels at the post synaptic cleft.

Question 6

What is the major protein connector of the electrical synapse?

Answer 6

Connexon

Question 7

What are some key characteristics of the electrical synapse

Answer 7

• The narrow gap makes the communication extremely fast.
• Permits easy flow of current
• Ions, ATP molecules can go through it

Question 8

What are connexons viewed as?

Answer 8

The entire functional unit

Question 9

What are connexins?

Answer 9

The individual connexon (spans both pre and post synaptic cells)

Question 10

What is the pore diameter of a connexon?

Answer 10

1.4nM (larger than most channels)

Question 11

What is the size of an electrical synapse?

Answer 11

About 3.5nM (small for direct transmission)

Question 12

What are some advantages of a electrical synapse with regards to speed?

Answer 12

Very fast

• It contains a depolarization current with a synaptic delay of 0.1ms

Question 13

What are some advantages of electrical synapses with regards to flow?

Answer 13

Can have a uni-or bi-directional flow

Question 14

What does the Uni or Bi directional flow in an electrical synapse do?

Answer 14

It synchronizes activity between neurons

Question 15

What are some examples of the synchronized activity between neurons as a result of uni or bi-directional flow?

Answer 15

• Regulation of breathing (brain stem)
• Posterior pituitary gland (oxytocin and vasopressin - ADH)

Question 16

What is the last advantage of an electrical synapse in regards to connections?

Answer 16

It connects neurons and glial cells.

Question 17

What is an electrical cardio gram?

Answer 17

Traces electrical signalling in the heart.

Question 18

What is the heart not made up of?

Answer 18

Neurons

Question 19

What is the cell type in the heart?

Answer 19

It is made up of cardiac muscle cells (myocytes)

Question 20

What do working myocytes produce in the heart?

Answer 20

Force

Question 21

What is the electrical signalling in the heart measuring?

Answer 21

Activation, then contraction

Question 22

What is the SA Node?

Answer 22

Considered the pacemaker of the heart. Its electrical signals normally cause the atria of an adult’s heart to contract at a rate of about 60 to 100 times a minute

Question 23

What are some characteristics of the chemical synapse?

Answer 23

It is slower, unidirectional and has a wider gap than electrical synapses (40 - 50mM)

Question 24

What is a chemical synapse dependent on?

Answer 24

Ca2+ neurotransmitter release.

Question 25

What is the Pre-Synpatic membrane of a chemical synapse?

Answer 25

Active Zones... location of neurotransmitter vesicle collections and internal membrane fusion.. exocytosis

Question 26

What is the Post-Synaptic Membrane of a Chemical Synapse?

Answer 26

More Density to support synaptic activity.

Question 27

What is a Ligand Gated Channel?

Answer 27

A ligand (Neurotransmitter) has to bind to it, in order for the channel to open and ions to flow through - Both a receptor and a channel

Question 28

What is an example of a Ligand Gated Channel?

Answer 28

The AchR (nicotine-Acetyl choline) receptor

Question 29

What are G-Protein Coupled Receptors?

Answer 29

- Can activate K+ channels in neurons - Modulation of action potentials.. the frequency - Mostly intracellular signalling, metabolism

Question 30

What is an example of a G-Protein Coupled receptor?

Answer 30

Epinephrine

Question 31

What are the series of events of G-protein coupled receptors?

Answer 31

Neurotransmitter binds, G protein is activated, G-protein subunits or intracellular messengers modulate channel, Ion flows across membrane, Ion channels open.

Question 32

What is your ventral horn?

Answer 32

The cell bodies of motor neurons that send axons via the ventral roots of the spinal nerves to terminate on striated muscles

Question 33

What is a Motor Unit?

Answer 33

One neuron and all the muscles fibres that surround it.

Question 34

What do somatic motor neurons innervate?

Answer 34

Skeletel muscles

Question 35

What can one motor neuron innervate?

Answer 35

Many muscle fibres

Question 36

What is each muscle fibre innervated by?

Answer 36

Only one motor neuron (you can't have two motor neurons plugged into same muscle fibre)

Question 37

What is excoystosis?

Answer 37

Moving cellular components from inside of cell to outside

Question 38

What are the three functions of exocytosis?

Answer 38

1.) Membrane Components - Adds molecules from vesicle interior (GLUT4) 2.) Recycle Endocytosis products 3.) Secretion (In to out) - Mucus - Neurotransmitters - WBC

Question 39

What is exocytosis done from?

Answer 39

Secretory Vesicles

Question 40

What is a Neuromuscular Junction?

Answer 40

The neuromuscular junction (NMJ) is a synaptic connection between the terminal end of a motor nerve and a muscle (skeletal/ smooth/ cardiac).

Question 41

What is the Neuro Muscular Junction a Site for?

Answer 41

It is the site for the transmission of action potential from nerve to the muscle.

Question 42

What is a patch (voltage) clamp recording?

Answer 42

Can manipulate a solution of Ach concentration and can inject a current

Question 43

What is a patch (voltage) clamp recording used for?

Answer 43

Examining behaviours of channels

Question 44

What are the recordings in a Patch (voltage) clamping recording?

Answer 44

I = current Downward, inward positive current.

Question 45

What is A Motor end plate?

Answer 45

The specialized postsynaptic region of a muscle cell.

Question 46

What is the Motor End Plate Potential Proportional To?

Answer 46

Calcium concentration

Question 47

How many Calcium do you need to release one vesicle?

Answer 47

4 Calciums

Question 48

What inhibits Ach?

Answer 48

Magnesium

Question 49

What is the relationship graph between Ca and EPP?

Answer 49

Non Linear

Question 50

How many vesicles for One Action Potential

Answer 50

About 100 to 300

Question 51

How many packets of Ach molecules released in one action potential?

Answer 51

5,000 to 10,000