Ch. 9&11 Review Questions Flashcards
(105 cards)
1
Q
This consists of the axon terminal of a motor neuron and the motor end plate of a muscle fiber.
A
Neuromuscular junction
2
Q
From what neuron do axons originate?
A
Motor neuron
3
Q
This is a microscopic space separating an axon terminal from a muscle fiber.
A
Synaptic cleft
4
Q
These are small membranous sacs filled with the neurotransmitter (ACh) acetylcholine in which they release.
A
Synaptic vesicles
5
Q
This is a folded region of sarcolemma under the axon terminal. It contains ACh receptors.
A
Motor end plate
6
Q
This breaks down ACh to prevent overstimulation of muscle fibers.
A
Acetylcholinesterase
7
Q
This occurs when a neuron sends information down an axon away from the cell body. They are caused when different ions cross the neuron membrane.
A
Action Potential
8
Q
During depolarization which ion is moving?
A
Na+
9
Q
What is repolarization and which ion is moving?
A
Repolarization is restoration of the initial polarized state (resting membrane potential).
K+ ion is moving
10
Q
This is a period where a cell cannot be stimulated again (usually during repolarization)
A
Refractory period
11
Q
How does the action potential activate contraction (E-C coupling)?
A
Action potential spreads along the sarcolemma and down the t tubule.
12
Q
Does ATP cause contraction or relaxation in the muscle fiber?
A
Relaxation
13
Q
What is the motor unit?
A
A motor neuron and all the muscle fibers it supplies.
14
Q
A muscle does not change in length but changes in tension with this type contraction.
A
Isometric
15
Q
A muscle changes length but not in tension with this type of contraction.
A
Isotonic
16
Q
What are the two types of isotonic contractions?
A
Concentric
Eccentric
17
Q
With this type of isotonic contraction, muscle tension rises to meet the resistance but then remains stable as the muscle shortens.
A
Concentric
18
Q
With this type of isotonic contraction muscle lengthens as the resistance becomes greater than the force the muscle is producing.
A
Eccentric contraction
19
Q
This is an increase in the frequency with which a muscle is stimulated increases the strength of contraction.
A
Wave summation
20
Q
This is rapid stimulation which creates sustained and quivering contractions. Incomplete.
A
Unfused tetanus
21
Q
This is stimulation that is fast enough for all evidence of muscle relaxation to disappear. Complete.
A
Fused tetanus
22
Q
This is multiple motor unit summation.
A
Recruitment
23
Q
Motor units recruited in order from smallest muscle fiber to largest is called?
A
Size principle
24
Q
What are the 3 pathways for regenerating ATP in muscle fiber?
A
- ADP and creative phosphate
- Glycolysis
- Aerobic respiration
25
This type of pathway for regenerating ATP uses no oxygen and it’s energy source is creating phosphate.
ADP and creatine phosphate
26
This type of pathway for regenerating ATP uses no oxygen and it’s energy source is glucose.
Glycolysis
27
This type of pathway for regenerating ATP uses oxygen and it’s energy sources include, glucose, pyruvic acid, free fatty acids from adipose, amino acids from protein catabolism.
Aerobic respiration
28
What 4 characteristics affect the force (strength) of muscle contractions?
1. Number of muscle fibers stimulated
2. Relative size of stimulation
3. Frequency of stimulation
4. Degrees of muscle stretch
29
What are the 3 muscle fiber types?
1. Slow oxidative fibers
2. Fast oxidative fibers
3. Fast glycolytic fibers
30
This type of muscle fiber is slow in duration and velocity and are red.
Slow oxidative fibers
31
This type of muscle fiber is fast in velocity and contraction and is white.
Fast oxidative fibers
| Fast glycolytic fibers
32
What are the 2 layers of smooth muscle tissue?
1. Longitudinal- long axis of organ
| 2. Circular- circumference of organs
33
What movement do the 2 layers of smooth muscle tissue produce?
Peristalsis
34
How does activation of smooth muscle differ from skeletal muscle?
Smooth muscle has
- no neuromuscular junctions
- no sarcomeres
- the nerve endings end in varicosities
35
How do the myofilaments differ in smooth muscle?
Smooth muscle has myosin heads along the entire length and can form additional cross bridges and latch on to actin.
36
How does contraction differ in smooth muscle vs skeletal muscle?
Smooth muscle has gap junctions which tell one to contract then sends signal to the next all the way down a line. Example small intestine.
37
What mechanism controls smooth muscle contraction?
Neural
| Hormones and local factors
38
Smooth muscle can adapt to new lengths and still contract on demand. There is no sarcomeres you can stretch and release and will go back to its original self. It is more flexible and responsive than skeletal. This describes what?
Stress-relaxation response
39
This is the ability of smooth muscle cells to divide and increase their numbers.
Hyperplasia
40
What are the 2 types of smooth muscle tissue?
1. Single unit visceral
| 2. Multiunit smooth muscle
41
This type of smooth muscle tissue the cells contract rhythmically and together as a unit.
Single unit visceral
42
This type of smooth muscle tissue has muscle fibers that are structurally independent and have many nerve endings. Their response to neural stimulation is graded (recruitment).
Multi-unit smooth muscle
43
What are the 3 functions of the nervous system?
1. Respond to information-motor output
2. Gather information- sensory input
3. Process and interpret information- integration
44
What are the 2 subdivisions of the nervous system and their functions?
1. Central nervous system- brain and spinal cord
| 2. Peripheral nervous system
45
What are the 2 cell types of nervous tissue?
1. Neurons
| 2. Neuralgia or glia
46
This cell type is excitable cells that transmit electrical signals.
Neurons
47
This type of nervous cell is a supporting cell that surrounds and wraps neurons.
Glia (neuralgia)
48
What are the 6 types of glia?
1. Astrocytes
2. Microglia
3. Ependymal
4. Oligodendrocytes
5. Schwann cells
6. Satellite cell
49
Which of the 6 type of glia are part of the CNS and which are part of the PNS?
Astrocytes, microglia, ependymal, and oligodenrocytes are part of the CNS
Schwann cells and satellite cells are part of the PNS.
50
This type of glia is the most abundant. It supports and braces neurons and lines blood capillaries.
Astrocytes
51
This type of glia monitors the health of neurons and serves as the immune system of the CNS.
Microglia
52
This type of glia lines central cavities of the brain and spinal cord. It circulated CNS fluid.
Ependymal
53
This type of glia wraps around thicker axons to create insulating myelin sheaths.
Oligodendrocytes
54
This type of glia surrounds neuron cell bodies (astrocytes).
Satellite cells
55
This type of glia forms myelin sheaths in the PNS (oligodendrocytes).
Schwann cells
56
What are the 4 characteristics that define a neuron?
1. Conduct electrical impulses
2. Extreme longevity- function optimally got a lifetime.
3. Amniotic- can’t divide to make more
4. High metabolic rate- require continuous and abundant supplies of nutrients and oxygen
57
What are the 2 parts of a neuron?
1. Cell body (soma)
| 2. Processes
58
This part of a neuron contains all the normal organelles of a cell except for centrioles.
Cell body or soma
59
This part of a neuron is an arm like projection from the neuron cell body. There are 2 types.
Processes
60
What are the 2 types of neuron processes?
1. Dendrites
| 2. Axons
61
Rough ER referred to as nissl bodies. Has many microtubules and microfilaments to maintain shape and stability. This describes characteristics of what?
Soma
62
These are short tapering branch like extensions off a neural body or soma. They are the receptive region of the neuron.
Dendrites
63
These can branch and end in 1000s of terminal branches. Impulses are conducted from the cell body to other cells. There is one per neuron.
Axons
64
This is a white, fatty, segmented covering. It protects and insulated axons, which increases the speed of transmission.
Myelin sheath
65
Which cells are responsible for making myelin in the CNS?
Oligodendrocytes
66
Which cells are responsible for making myelin in the PNS?
Schwann cells
67
This is a gap between Schwann cells where axon is exposed.
Node of Ranvier
68
What are the 3 structural classifications of neurons?
1. Unipolar
2. Bipolar
3. Multipolar
69
What are the 3 functional classifications of a neuron?
1. Sensory- afferent
2. Motor- efferent
3. Interneuron/Association
70
What are the 4 membrane ion channel classes?
1. Ligand gated channels
2. Voltage gated channels
3. Mechanically gated channels
4. Leakage channels
71
This membrane ion channel requires a chemical “key”.
Ligand gated channel
72
This membrane ion channel requires changes in membrane potential
Voltage gated channels
73
This membrane ion channel requires physical deformation (touch and pressure receptors).
Mechanically gated channel
74
This membrane ion channel is always open.
Leakage channel
75
What is the membrane resting potential in a neuron?
Inside of the neuron has more negative charge than the outside.
76
Which ion is responsible for generating the resting membrane potential?
K+
77
K+ effluent undershirts resting membrane potential. The membrane becomes more negative than at rest and decreases charge of nerve impulse.
Hyperpolarization
78
Increased Na+ permeability and reversal of membrane potential is called what? The membrane becomes more positive and increases the chance of nerve impulse.
Depolarization
79
These are changes in membrane potential that vary in size, as opposed to being all-or-none. Current decreases in magnitude with distance from stimulus.
Graded potential
80
What occurs during the 4 stages of an action potential?
1. Resting state
2. Depolarization
3. Repolarization
4. Hyperpolarization
81
What occurs during the resting state of an action potential?
Voltage gated channel is closed
82
What occurs during the depolarization state of an action potential?
Increased Na+ permeability
83
What occurs during the repolarization stage of an action potential?
Decreased Na+ permeability and increase K+ permeability.
84
What occurs during the hyperpolarization stage of an action potential?
K+ efflux undershoots membrane potential.
85
What restores the electrical balance and what restores the ion balance?
Repolarization restores the electrical balance.
| Sodium potassium pump restores the ion balance.
86
These are periods where a cell cannot be stimulated again (usually during repolarization).
Refractory period
87
What are the two major types of synapses?
1. Electrical
| 2. Chemical
88
What is the presynaptic and postsynaptic neuron?
Presynaptic is the sending neuron.
| Postsynaptic is the receiving neuron.
89
This type of synapse has cells that are electrically coupled. Ions flow directly from one cell to another. Gap junctions.
Electrical synapse.
90
This type of synapse is release and reception of chemical neurotransmitters. There are two parts including axon terminal of presynaptic neuron and receptor region of postsynaptic neuron.
Chemical synapse
91
What are the 2 postsynaptic potentials?
1. Excitatory postsynaptic synapses (EPSP)
2. Inhibitory postsynaptic synapses.
(IPSP)
92
This postsynaptic potential allows Na+ and K+ to flow freely across the membrane leads to small depolarization.
Excitatory synapses
93
This postsynaptic potential allows K+ or Cl- to flow. It creates small hyperpolarization.
Inhibitory synapse
94
What is temporal summation?
Before postsynaptic potentials dissipates a second postsynaptic potential is added to it.
95
What is spatial summation?
Postsynaptic potentials from all parts of the neuron are added together at the same time.
96
This is repeated or continuous use of a synapse enhancing presynaptic neurons ability to excite postsynaptic neurons.
Synaptic potentiation
97
This is the release of excitatory neurotransmitter is inhibited by an anoaxonic synapse from another neuron.
Presynaptic inhibition
98
What are the 6 chemical classes of neurotransmitters?
1. Acetylcholine
2. Biogenic amines
3. Amino acids
4. Peptides
5. Purines
6. Dissolved gases
99
What is an example of biogenic amines?
Catecholamines such as dopamine, epinephrine, serotonin and histamines
100
What is an example of amino acids?
Glycine
Aspartame
Glutamate
101
What are examples of peptides?
Substance P
| Endorphins
102
What are examples of purines?
Adenine
Guanine
ATP
103
What are examples of dissolved gases?
```
Nitric oxide (NO)
Carbon monoxide (CO)
```
104
What are the functional classes of neurotransmitters?
1. Excitatory- glutamate
2. Inhibitory- GABA and glycine
3. Direct- bind to ion channels
4. Indirect- bind to receptors that activate 2nd messengers
105
What are the 2 neurotransmitter receptor types and how do they differ?
1. Channel linked receptor
| 2. G-protein linked receptors
