Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy & Physiology > Nerves & Muscles > Flashcards

Nerves & Muscles Flashcards

1
Q

What is the nervous system?

A

A network of nerve cells (neurons) and fibres that transmit nerve impulses between parts of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What structures make up the CNS?

A

Brain & Spinal Cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What structures make up the PNS?

A

Nerves not in the brain or spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the autonomic nervous system?

A

Part of the nervous system responsible for involuntary movements made up of both the PNS and CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Do dendrites send afferent or efferent signals?

A

Afferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Do Axons send afferent or efferent signals?

A

Efferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What makes up the phospholipid bilayer?

A

Hydrophilic Phosphate Heads and Hydrophobic Lipid Bodies/Tails

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is needed for ions (charged) to pass through the phospholipid bilayer?

A

Channels or transporters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Are there more potassium (K+) cells inside than outside of the cell? and by how many?

A

30x more inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Are there more Na+, Cl- and Ca2+ ions inside or outside the cell?

A

Outside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What maintains the cell membrane charge/potential?

A

The outflow of K+ ions via potassium channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

At rest, what are ions are cell membranes most permeable to?

A

Potassium (K+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Does the sodium-potassium pump maintain or establish a cells membrane potential?

A

Establishes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is depolarisation?

A

The polarity of the cell becoming more positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is hyperpolarisation?

A

The polarity inside the cell becoming more negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the ‘potassium diffusion potential’?

A

K+ diffusing the concentration gradient across the neuronal cell membrane via K+ leaky channels that causes the cell to become more negative compared to outside the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Is the ‘potassium diffusion potential’ passive or active?

A

Passive - it goes with the concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

At what voltage do nerve cells reach equilibrium?

A

At -74mV where K+ outflow is equal to inflow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Is the sodium-potassium pump passive or active?

A

Active - it’s ATP activated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How many sodium and potassium ions are pumped out/in in the sodium-potassium pump?

A

3 x Na+ ions OUT
2 x K+ ions IN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the ‘resting negative membrane potential’?

A

The diffusion of ions on either side of the cell membrane, membrane permeability to different ions and the action of the sodium-potassium pump

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the process that occurs during an action potential?

A

1) The membrane potential hits -55mV due to stimulus
2) Voltage-gated sodium channels open and sodium (Na+) flows into the cell via the concentration gradient (passive) which depolarises the cell.
3) At around +40mV the voltage-gated sodium channels close and voltage-gated potassium channels open causing K+ ions to rapidly go down the concentration gradient = repolarisation
4) However, K+ are slow to close leading to hyperpolarisation (going beyond the -74mV resting state).
5) RMP is restored once both the Na+ and K+ have closed which is restored mainly by the K+ outflow from leaky channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the ‘absolute refractory period’?

A

When there are no further action potentials available as voltage-gated sodium channels have already started an AP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the ‘relative refractory period’?

A

Once voltage-gated Na+ close but K+ open for hyperpolarisation a stronger stimulus is needed to reach the threshold (-55mV) for another AP to occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the process of faster conduction along myelinated nerve fibres called?

A

Saltatory conduction

26
Q

What lies between each myelinated section of an axon?

A

Nodes of Ranvier

27
Q

Myelin is produced by which neuroglia in the PNS and CNS?

A

PNS - Schwann Cells
CNS - Oligodendrocytes

28
Q

Action potentials travel in both directions, what dictates the direction of the impulse?

A

Chemical synapses

29
Q

How do chemical synapses occur?

A

1) AP arrives at the pre-synaptic neuron
2) Calcium voltage-gates open
3) Calcium diffuses into the pre-synaptic neuron
4) The synaptic vesicle moves with the neurotransmitters across the cell membrane
5) The vesicle fuses with the membrane an allow the ACh to diffuse across the synpatic cleft to the post-synaptic neuron (Noradrenaline at the post-synaptic)

30
Q

What neurotransmitter occurs pre and post-ganglionic in the:
1) Skeletal Muscles?
2) Parasympathetic System?
3) Sympathetic System?

A

1) Skeletal Muscle - ACh only. Voluntary movements.
2) Parasym. (rest & digest) - ACH both pre-and-post ganglionic receptors
3) Sympathetic (fight or flight) - ACh at pre-ganglionic and Epinephrine and Norepinephrine for post-ganglionic

31
Q

Neurotransmitter molecules can attach to neurotransmitter receptors. What are the two types of receptors?

A

Ionotropic (open/close ion channels, fast, all or nothing and trigger APs)
or
Metabotropic (slower on/off, amplify or dampen signals, trigger post-synaptic events including APs)

32
Q

What are the three types of muscle?

A

Skeletal, Smooth and Cardiac

33
Q

What are the features of skeletal muscle?

A

Striated, multinucleated, tubular fibres and under voluntary control

34
Q

What are the features of smooth muscle?

A

Non-striated, uninucleated, involuntary control and responsible for veins etc.

35
Q

What are the features of cardiac muscle?

A

Striated, uninucleated, branched and under involuntary control

36
Q

What is the skeletal muscle micro-anatomy?

A

Muscle cell (myocyte) are muscle fibres –> a bundle of multinucleated myofibrils make up a contractile unit called a sarcomere and can either be thin (actin) or thick (myosin) –> a bundle of myocytes have surrounding connection tissues called endomysium and make up a fascicle –> Perimysium sheath fascicles –> epimysium sheath perimysium

37
Q

What part of skeletal muscles want to move together by attaching and moving past one another in the sliding filament mechanism?

A

Myofibrils

38
Q

What does myosin want to bind to during the sliding filament mechanism?

A

Myosin wants to bind to Actin

39
Q

What is blocking the way during the sliding filament mechanism?

A

Troponin-Tropmyosin complex

40
Q

What can expose the actin binding site during the sliding filament mechanism?

A

Calcium

41
Q

What is the process for muscle contraction?

A

1) AP arrives in the terminal axon causing an influx of Ca2+
2) Increased Ca2+ stimulates the release of ACh into the synaptic cleft which depolarises the cell.
(Botox prevent ACh from going into the cell)
3) Once depolarises, the muscle holds calcium in troponin.
4) ACh bind to ligand-gated ion channels (nicotinic ACh receptors) that generates an AP along the muscle fibre
5) T-tubles conduct APs to sarcoplasmic reticulum which releases Ca2+ into sarcoplasm.
6) This calcium binds to the troponin which exposes the binding site for myosin
7) ATP binds to myosin which hydrolyses to ADP and Phosphate
8) Myosin head binds to Actin and bends which releases ADP and Phosphate
9) A new molecule of ATP will then bind to the myosin head which would detach from actin myofibril

42
Q

How does muscle relaxation occur?

A

Sarcoplasm pumps Ca2+ out into the sarcoplasmic reticulum and then troponin-tropmyosin slides back into position by blocking the actin binding site.
At the neuromuscular junction AChE (acetylcholinesterase) breaks down ACh to allow for transmission.

43
Q

What type of poisoning inhibits AChE?

A

Organophosphate Poisoning

44
Q

What are muscle cells called?

A

Myocyte

45
Q

A bundle of what make up a contractile unit?

A

Myofibrils

46
Q

What’s the name of a contractile unit?

A

Sarcomere

47
Q

What is thin or thick sarcomere called?

A

Thin = Actin
Thick = Myosin

48
Q

What is the surrounding connection tissues around a bundle of myocytes called?

A

Endomysium

49
Q

What makes up a fascicle?

A

Endomysium

50
Q

What sheaths fascicles?

A

Perimysium

51
Q

What sheaths perimysium?

A

Epimysium

52
Q

What is pumped out of the sarcoplasmic reticulum for troponin-tropmyosin for muscle relaxtion?

A

Calcium

53
Q

In muscle contraction how does the cell become depolarised?

A

Ca2+ stimulates the release of ACh into the synaptic cleft

54
Q

What does botox prevent?

A

ACh from going into the cell

55
Q

In muscle contraction, what does ACh bind to?

A

Ligand-gated ion channels

56
Q

During muscle contraction, what are action potentials conducts by?

A

T-tubles

57
Q

In muscle contraction, what does myosin bind to?

A

Actin

58
Q

What does ATP bind to? What does it hydrolyses to?

A

Myosin and to ADP and Phosphate

59
Q

Once myosin binds to actin it bends to release what?

A

ADP and Phosphate

60
Q

What causes the myosin head from detaching from actin myofibrils?

A

A new molecule of ATP

Anatomy & Physiology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions