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Neurophysiology Flashcards

1
Q

The nervous system consists of two major divisions: ____ and _____.

A

Central Nervous System (CNS) and the Peripheral Nervous System.

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2
Q

Function of the Nervous System

A
  • Control and communicate activities of the body.
  • Regulate all bodily activities
  • Interpret and commands activities of the body
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3
Q

The functions are overlapping and follow the order: (3)

A
  1. Sensory (Input of information) 2. Integration (Process and Translate)
  2. Motor Output (Effect Activity)
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4
Q

• Consists of the brain and spinal cord
• Occupies the dorsal cavity
- Integrative and control center
- Brain and Spinal Cord

A

CNS

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5
Q

A complex set of brain structures that lies on both sides of the thalamus, right under the cerebrum.
- It supports a variety of functions, including emotion, behavior, motivation, long-term memory, and olfaction.

A

Limbic System

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6
Q

It comprises multiple subcortical nuclei, of varied origin, in the brains of vertebrates, which are situated at the base of the forebrain. It is strongly interconnected with the cerebral cortex, thalamus, and brainstem, as well as several other brain areas.
- It is associated with a variety of functions including: control of voluntary motor movements, procedural learning, routine behaviors or “habits” such as bruxism, eye movements, cognition and emotion.

A

Basal Nuclei

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7
Q

A region in the brainstem that is involved in multiple tasks such as regulating the sleep-wake cycle and filtering incoming stimuli to discriminate irrelevant background stimuli.
- It is essential for governing some of the basic functions of higher organisms, and is one of the phylogenetically oldest portions of the brain.

A

Reticular Formation Centre

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8
Q

A brain structure located in the mesencephalon (midbrain) that plays an important role in reward, addiction, and movement.

A

Substantia Nigra

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9
Q

the crossing of the fibers of the corticospinal tracts from one side of the central nervous system to the other near the junction of the medulla and the spinal cord

A

Decussation of Pyramids

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10
Q

A set of connected nuclei in the brains of vertebrates that is responsible for regulating arousal and sleep-wake transitions. As its name implies, its most influential component is the reticular formation.

A

Reticular Activation System (RAS)

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11
Q

An area of motor cortex lying within the frontal lobe of the brain just anterior to the primary motor cortex. It occupies part of Brodmann’s area
- The functions are diverse and not fully understood. It projects directly to the spinal cord and therefore may play a role in the direct control of behavior, with a relative emphasis on the trunk muscles of the body. It may also play a role in planning movement, in the spatial guidance of movement, in the sensory guidance of movement, in understanding the actions of others, and in using abstract rules to perform specific tasks

A

Pre-motor Cortex

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12
Q

It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two of these, one in each side of the brain. It is located under the cerebral cortex.

A

Hippocampus

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13
Q

• Is composed of nerves and ganglia
• Functional, the ____ is divided into sensory and motor divisions and each of these divisions is sub-sectioned into somatic and visceral divisions.
- Communication lines between CNS and the rest of the body

A

PNS

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14
Q
  • Somatic and visceral sensory fibers

- Conducts impulses from receptors to CNS

A

Sensory (afferent) division

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15
Q
  • Motor nerve fibers

- Conducts impulses from the CNS to effectors (muscles and glands)

A

Motor (efferent) division

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16
Q
  • Visceral motor (involuntary)

- Conducts impulses from the CNS to cardiac muscles, smooth muscles, glands

A

ANS - Autonomic Nervous System

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17
Q
  • Somatic motor (voluntary)

- Conducts impulses from the CNS to the skeletal muscles

A

SNS - Somatic Nervous System

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18
Q

Mobilizes body systems during activity. Fight or flight.

A

Sympathetic Division

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19
Q

Conserves energy and promotes housekeeping functions during rest.

A

Parasympathetic Division

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20
Q

Sensory (Afferent) Division: (2 subdivisions)

A
  1. Somatic sensory division

2. Visceral sensory division

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21
Q

Division that carries signals mainly from the viscera of the thoracic and abdominal cavities (organs such as the heart, lungs, stomach and urinary bladder) to the CNS.

A

Visceral sensory division

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22
Q

Division that carries signals from receptors in the skin, muscles, bones and joints to the CNS

A

Somatic sensory division

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23
Q

Carries signals from the CNS mainly to muscles and gland (Effectors)

A

Motor (Efferent) Division

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24
Q

2 subdivisions of motor (efferent) division

A
  1. Somatic motor division

2. Visceral motor division

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25
Q

Motor division that carries signals to skeletal muscles (the signs cause voluntary and involuntary muscle contraction).

A

Somatic motor division

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26
Q

Motor division that carries signal to gland cardiac muscle and smooth muscle. The functions are involuntary controlled and the system operates at the unconscious level. The AUTOMONIC NERVOUS SYSTEM (ANS) is a part of this division.

A

Visceral motor division

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27
Q

Two types of neural tissue.

A

neuroglia and neurons

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28
Q

Neuroglia outnumber neurons by a ratio of ____

A

10:1

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29
Q

Neuroglia number about _____ minimum, in a young person

A

10 000 million

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30
Q

Function of Neuroglia (4)

A
  • Uptake of released neurotransmitters, e.g., uptake of GABA
  • Development & Maintenance of the nervous system, e.g., multiple and an occupy areas from which neurons are lost. (Brain Tumours arise from glia cells since neurons do not undergo mitosis.)
  • Provide mechanical support for neurons and prevent electrical interference between neuron by insulating neuron axons
  • Form the blood brain barrier. Blood-Brain barrier is a concept based on the observation that certain chemicals transported in the blood which can get to soft tissue such as liver and kidney are prevented from reaching brain tissue.
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31
Q

Neuroglia (Glial Cells) in the CNS (4)

A
  1. Oligodendrocytes
  2. Ependymal cells
  3. Microglia
  4. Astrocytes
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32
Q

Neuroglia (Glial Cells) in the CNS

- form myelin in the brain and spinal cord that cover thicker neuron fibres

A

Oligodendrocytes

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33
Q

Neuroglia (Glial Cells) in the CNS
- line cavities of the brain and spinal cord; secrete and stir cerebrospinal fluid (CSF) to promote circulation of the CSF.

A

Ependymal cells

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34
Q

Neuroglia (Glial Cells) in the CNS

- the scavenger neuroglia; phagocytes that destroy microorganisms, foreign bodies and dead neural tissue.

A

Microglia

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35
Q

Neuroglia (Glial Cells) in the CNS
- most abundant neuroglia; cling to neurons and their synaptic ending; cover blood capillaries; brace and anchor neuron into position; control environment around neurons; influence neuron function and participate in information process in the brain; nourish neurons; act to form blood-brain-barrier; form scar tissue to replace damage neural tissue.

A

Astrocytes

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36
Q

Neuroglia in the PNS (2)

A
  1. Schwann cells

2. Satellite cells

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37
Q

Neuroglia in the PNS
- wrap around the larger axons of nerve fibres; assist in the regeneration of damage nerve fibre; aid conduction of action potential.

A

Schwann cells

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38
Q

Neuroglia in the PNS

- surround cell bodies of neurons located in ganglion (in PNS).

A

Satellite cells

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39
Q

Myelin lipid (whitish, fatty) layer that surround long and large diameter nerve fibres; it forms a _____.

A

myelin sheath

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40
Q

The myelin sheath is formed by spiralling layer of plasma membrane of an _____ or ______.

A

Oligodendrocyte or Schwann cells

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41
Q

Myelin sheath is associated only with the axons of a _____.

A

nerve fibre

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42
Q

_____ of nervous system begins in the 14th of foetal development and ends in late adolescence.

A

Myelination

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43
Q

In both PNS and CNS nerve fibres are much longer than a single glial cell; hence several glial cells are required to cover a fibre. The myelin sheath, therefore appear on the fibre in segments, hence the __________.

A

Nodes of Ranvier

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44
Q

Myelin protects and insulate ____.

A

fibres

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45
Q

Myelin increase the speed transmission of _____.

A

nerve impulses

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46
Q

__________ are found in the CNS and PNS. In both PNS and CNS small-diameter axons are unmyelinated.

A

Unmyelinated nerve fibres

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47
Q

In the PNS on Schwann cell may surround _____ small nerve fibres.

A

1-12

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48
Q

Regions of the CNS containing dense collection of myelinated fibres are referred to as _____ matter.

A

white matter

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49
Q

Grey matter contains mostly cell bodies and ______.

A

unmyelinated fibre

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50
Q

Disorders of Myelin (2)

A
  1. Multiple sclerosis

2. Tay-Sach disease

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51
Q

PROPERTY OF NEURON (3)

A
  1. Excitability 2. Conductivity
  2. Secretion
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52
Q

All cells are excitable when stimulated by environmental stimuli.

A

Excitability

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53
Q

product electrical signal (action potential) that can travel to another cell.

A

Conductivity

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54
Q

secrete a chemical (neurotransmitter) that aid in the transmission of the electrical signal.

A

Secretion

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55
Q

FUNCTIONAL CLASSES OF NEURON (3)

A
  1. Sensory (Afferent) Neurons
  2. Interneurons (association neurons)
  3. Motor (Efferent) Neurons
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56
Q

• neurons that detect stimuli such as light, heat, pressure; transmit information about stimuli to CNS; conducts to

A

Sensory (Afferent) Neurons

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57
Q

• neurons that lie entirely with the CNS; receive information from many neurons;

  • process, integrate, store, retrieve information; make decisions.
  • make up over 90% of all the body’s neurons.
A

Interneurons (association neurons)

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58
Q

Neurons that send information mostly to muscles and glands; conduct action potential away from the CNS.

A

Motor (Efferent) Neurons

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59
Q

NEURON STRUCTURE (4)

A
  1. Anaxonic
  2. Unipolar
  3. Bipolar Neurons
  4. Multipolar neurons.
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60
Q

Neurons that have multiple dendrite but no axon; communicate through their dendrite; do not produce action potential; found in the brain, retina and adrenal medulla.

A

Anaxonic neurons

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61
Q

Neurons that carry sensory information to the Spinal cord from the periphery; have branching dendrites in the skin; cell bodies dorsal ganglion.

A

Unipolar Neurons

62
Q

Rare neurons that found in some sense organs (e.g., retina of eye and olfactory mucosa)

A

Bipolar Neurons

63
Q

Most common type of neuron in the body (over 99% of all neurons).

A

Multipolar neurons

64
Q

Within the axon material is transported via ______ of the cytoskeleton.

A

microtubules

65
Q

The motors that carry the materials are _____.

A

proteins (transport proteins)

66
Q

Transport proteins have ____ and ____ and carry material on their

A

cilia and flagella

67
Q

There is a two-way conduction within the neuron axons: (2)

A

1) Anterograde transport

2) Retrograde transport

68
Q

Transport that involves the movement of material such as proteins and chemicals made in the soma (cell body) to the axon membrane (e.g., protein for membrane repair) and axon terminals (e.g., acetylcholine, amino acids, glucose).

A

Anterograde transport

69
Q

Transport that involves the movement of substances from the axonal terminal to the soma for recycling and disposal. Substance transported by this means include Herpes virus, polio virus, and tetanus toxin.

A

Retrograde transport

70
Q

The potential energy generated by charged particles such as electrons and ions.

  • is measured in volts (1 mV = 0.001V)
  • is the difference in potential energy between two point in an electric field.
A

Voltage

71
Q

The flow of charged particle (electron, ion) from one point in an electric field to another. It is measured in ampere (A); 1mA = 0.001A

A

Current

72
Q

The hindrance of flow to current flow through a material.

A

Resistance

73
Q

Resistance in a conductor is measured in ____.

A

ohms

74
Q

If the resistance is high in a material the material is called an ______;

A

insulator

75
Q

Tif the resistance is low, the substance is called a ____.

A

conductor

76
Q

Voltage across a plasma membrane

A

Membrane Potential

77
Q

The state of a plasma membrane of an un-stimulated cell membrane. The inside of the cell membrane is relatively negative (compared to the outside) because more protein is inside than outside the cell. (Protein carries a negative charge.) The outside is more positive because of high Na+ conc’n. and the inability of Na+ to diffuse easily across the membrane. In the polarized state, the number of K+ moving out of the cell equals the number of K+ moving inside the cell.

A

Polarized

78
Q

The voltage across a plasma membrane that is un-stimulated (polarized). It is caused mainly by differences in intracellular and extracellular ions.

A

Resting Membrane Potential (RMP)

79
Q

RMP results from the combination of (3)

A
  1. Diffusion of ion down concentration gradient

2. Selective permeability of the plasma membrane; 3. The attraction of cations and anions to each other.

80
Q

____+ has the largest influence on RMP

A

K+

81
Q

RMP for neurons is approximately ____ mV (inside negative)

A

-70 mV

82
Q

When the RMP is changed so that the inside of the cell become less negative, the membrane is said to be _____.

A

depolarized

83
Q

______ are openings in large proteins often with subunits whose amino acids chains twist backward and forward across the plasma membrane.

A

Ion Channels

84
Q

Types of channel include: (4)

A

a) Chemical-gated (ligand-gated) channels
b) Voltage-gated channel
c) Mechanically-gated channel
d) Non-gated/ Leakage channel

85
Q

Type of Channel
- part of the protein molecule forms a gate that opens or closes in response to certain chemical. The gate opens only when specific chemical binds e.g., neurotransmitter.

A

Chemical-gated (ligand-gated) channels

86
Q

Type of Channel

- opens and closes in response to changes in membrane potential

A

Voltage-gated channel

87
Q

Type of Channel

- opens and closes when physical action is apply (e.g., when sensory receptor for pressure, touch are deformed)

A

Mechanically-gated channel

88
Q

Type of Channel
– these channels are always open but channel is selective as to which ion passes through (e.g. K+ channels allow only K+ to pass through.

A

Non-gated/ Leakage channel

89
Q

When gated ion channels are open the ions diffuse quickly through the gate (down their concentration gradient). The ion flow constitutes an electric current which is called an _______.

A

impulse or action

90
Q

______ are proteins that active to moving certain substance into or out of cell; they tend to move substance from low concentration to high concentration (i.e., up concentration gradient).

A

Membrane pumps

91
Q

_______ is an enzyme that hydrolyses ATP (ATP ADP + P + energy to pump).

  • This pump, in each cycle of action, moves 3 Na+ from inside the cell to the extracellular fluid and simultaneously, brings 2K+ into the intracellular fluid by using 1 molecule ATP for energy.
  • Notice that this pump stabilizes the resting membrane potential by maintain the ion concentration gradient across the membrane.
A

Na+/K+ pump (Na+/K+ ATP-ase)

92
Q

A rapid voltage change in which a plasma membrane briefly reverses electrical polarity.

A

ACTION POTENTIAL (AP)

93
Q

All functional body cells generally exhibit a resting membrane potential (RMP) but muscle and nerve cells are able to alter the cross membrane potential by _____

A

depolarization

94
Q

The shift in potential difference from positive to negative (outside the cell membrane) is called an _______.

A

action potential (AP.)

95
Q

A state in which the plasma membrane becomes more positive than the resting membrane potential

A

Depolarization

96
Q

An increase in membrane potential in which the membrane becomes more negative than the resting membrane potential.

A

Hyperpolarisation

97
Q

Action potential (AP) in neurons has amplitude of about ___ mV and last for 1ms.

A

110 mV

98
Q

The generation of AP is the result of a stimulus by a _______(e.g., light, heat, electrical energy or mechanical force). The stimulus causes the membrane to become permeable to Na+ leading to depolarization of the membrane. (This is an example of a positive feedback system while the Na+ that crosses the membrane cause more Na+ to enter the cell , until Na+ inside = Na+ outside the cell.) Following depolarization, K+ leaves the cell making the inside less positive, in an effort to restore the RMP.

A

form of energy

99
Q

Restoration of the RMP is brought about by the outward diffusion of ___+.

A

K+

100
Q

_____ occurs following repolarisation. K+ diffusion out of the cell dominates repolarisation. Generally, so much K+ diffuse out of the cell that the membrane potential to fall below the RMP, a condition called _______.

A

Hyperpolarisation

101
Q

Following hyperpolarisation, the Na+/K+ pump resorts the cross membrane ion conc’n. by pumping __+ out __+ into the cell

A

Na+ out K+ in

102
Q

AP obeys the _____ law. That is, they are not graded responses; they either full-size or absent depending on the stimulus. AP produced by any neuron has a constant size of 110mV and last for 1 ms. amplitude and duration do not vary with frequency of stimulation. If the stimulus depolarizes the neuron to the threshold, the neuron fires to its fullest level. If the threshold is not reached the neuron will not fire.

A

all-or-none law

103
Q

True or False

The last potential at the end of a fibre is as strong as the first AP.

A

True

104
Q

True or False

AP goes to completion; it cannot be stopped once started.

A

True

105
Q

A short range change in voltage.

  • Occurs when a dendrite is stimulated by stimuli such as heat, light, pressure, pain signal from damaged tissue. Stimulation causes voltage regulated Na+ gates to open and allow Na+ into the plasma membrane of nerve cells. Inflow of Na+ leads to neutralization of negative charges and move the membrane voltage towards zero (i.e., causes depolarization to occur). Sodium only travels a short distance along the plasma membrane from the receptor end to the cell body of neurons.
  • gets weaker as it travels to the soma
  • vary in strength and can be quickly reverse as K+ leaves intracellular fluid
  • can cause depolarization or hyperpolarisation.
A

LOCAL POTENTIAL

106
Q

Virtually all voltage regulated Na+ and K+ channels are closed at the ____.

A

resting membrane potential (RMP)

107
Q

II. ____ zones of neurons have many voltage regulated gates (more than the soma of neurons).

A

Trigger zones

108
Q

III. Local potential that spreads through a membrane to reach the trigger zone can cause voltage regulated gates to open, if the signal is ______.

A

strong enough

109
Q

IV. If local potential causes membrane voltage to rise to the threshold voltage (~ -55mV) the neuron “____”. If the local potential is < -55 mV the neuron _____ (i.e., all-or-none).

A

fires; does not fire

110
Q

V.Threshold voltage is reached by means of

4

A
  1. Na+ gates opening quickly and let in Na+.
  2. K+ gates opening slowly to let K+ out.
  3. Influx of Na+ causes other Na+ gates to open (Positive Feedback)
  4. Influx of positive ions leads to rapid rise in membrane potential
111
Q

VI. When membrane potential reaches 0 mV, _______ start closing. By the time all gates are closed membrane voltage has climbed to + 35 mV to 50 mV (Peak voltage).

A

Na+ gates

112
Q

VII. At peak voltage all the K+ gates are open and _____ is occurring. K+ gates stay open longer than Na+ gates.
- So efflux of K+ > influx of Na+.

A

efflux of K+

113
Q

VIII. _____ causes the membrane potential to move towards zero and the RMP (Repolarisation). But since diffusion of K+ levels is greater than influx of Na+ the plasma membrane becomes more negative than the RMP ( i.e., hyper-polarization occurs). By the end of hyper-polarization K+ gates are closed and the cell will respond to a new stimuli.

A

Diffusion of K+

114
Q

Peak voltage

A

+ 35 mV to 50 mV

115
Q

During an action potential and a few milliseconds after, the neuron will not respond to stimuli. This period is called the ________.
- This period refers only to a small patch of membrane where the AP has already begun, not to the entire neuron.

A

refractory period

116
Q

Action potential follows a lit fuse or _____.

A

domino effect

117
Q

• Na + open in a region, Na+ influx occurs then the Na+ gates close (_______occurs)

A

depolarization

118
Q

Depolarization in one region causes depolarization in the ____ region and AP spreads along the axon to the axon terminal.

A

adjacent region

119
Q

• AP does not move backwards because of _____________.

A

refractory period in previously depolarized region

120
Q
  • Signal is slow (~ 2m/s)

- Signal does not grow weaker as it spreads _____; signal strength stays the same.

A

forward

121
Q

_____ blocks the movement of ions into the neuron and voltage gates are few in the internodes’ regions.

A

Myelin

122
Q

Most voltage gates are located in the _____.

A

Nodes of Ranvier

123
Q

Na+ enter at the nodes causes an AP and diffuse along the _____.

A

axolemma

124
Q

Myelin weakens signal strength so the sign can only travel ___mm before it become too weak to affect an adjacent node.

A

1mm

125
Q

When sign from one node reaches an adjacent node it opens Na+ voltage gate at that node and ____ occur.

A

Na+ influx

126
Q

At each node influx of Na+ occurs followed by an ____, hence signal appear to jump from node to node (SALTATORY CONDUCTION).

A

AP

127
Q

The propagation of nerve signal that seems to jump from one node to another.

A

Saltatory conduction

128
Q

Conduction velocity up to ____m/s.

A

120m/s

129
Q

A ____ is a bundle of nerve fibres (axons) wrapped in fibrous connective tissue.

A

Nerve

130
Q

Nerves originate from the CNS and travel through ___ of the skull and _____. They carry signal to and the CNS to other parts of the body.

A

foramina; vertebral column

131
Q

____ nerve refers to the fact that the nerve contains both afferent and efferent nerve fibres innervating a number of different muscles and glands.

A

Mixed nerve

132
Q

Each nerve is wrapped in delicate fibrous connective tissue called ____ and groups of nerve fibres are held together in bundles called _____. The bundles of nerve fibres are all enclosed in an outer fibrous covering called _____.

A

endoneurium; perineurium; epineurium

133
Q

Speed of conduction on a nerve fibre depends on (2)

A

1) diameter size and 2) myelination:

134
Q

Since signal conduction occurs at the surface (rather than deep within the axon), the larger the diameter of the fibre the ____ the conduction of the action potential. This implies that the smaller the fibre the ___ the conduction.

A

Faster; Slower

135
Q

True or False

Myelinated fibres conduct much faster and farther those unmyelinated fibres

A

True

136
Q

Conduction speed in a fibre of diameter 2-4 micrometers, unmyelinated:

A

0.5-2 m/s

137
Q

Conduction speed in a fibre of diameter 2-4 micrometers, myelinated:

A

3-15m/s

138
Q

Conduction speed in large diameter fibres (up to20 micrometres) is as fast as _____m/s.

A

120m/s

139
Q

____ fibres used where speed is important, e.g. signal to muscles, sensory input from vision and balance.

A

Fast fibres

140
Q

____ fibres employed in processing information in which rapid response not required, e.g., secreting stomach acid, dilating the pupil.

A

Slow fibres

141
Q

At the axonal terminals AP depolarizes the axolemma to cause Ca++ to enter and binds to ____.

A

vesicles

142
Q

The vesicles with Ca++ migrate to the membrane, binds and empty their content (neurotransmitter) in the _____.

A

gap

143
Q

Four categories of neurotransmitters are released by neurons: (4)

A
  1. Acetylcholine (Ach)
  2. Amino Acids
  3. Monoamines
  4. Neuropeptides
144
Q

There are two types of synapse:

A
  1. Excitatory synapse and EPSP

2. Inhibitory synapse and IPSP

145
Q

At _______ synapse, neurotransmitter binding causes depolarization of the postsynaptic membrane. Binding of the neurotransmitter to chemical gates causes the opening of Na+ and K+ gates and the ions to flow in opposite direction. The net effect is membrane depolarization. If enough neurotransmitter binds to the membrane, so that the membrane threshold voltage is reached, then the neuron fires. Otherwise, it does not fire. Since post-synaptic membrane cannot generate AP (because the membrane have not voltage gate) only a local graded depolarization event called excitatory postsynaptic potential (EPSP) occurs. The function of an EPSP is to help trigger action potential at the axon hillock of the post-synaptic neuron.
If the current that reaches the axon hillock is strong enough to depolarize the axon to its threshold voltage, then voltage gates on the axon open and the neuron fires. Examples of excitatory neurotransmitter are: Ach, NE and E.

A

Excitatory synapse and EPSP

146
Q

At ______ synapse, neurotransmitter binding inhibits the postsynaptic neurons ability to generate action potential. Most inhibitory neurotransmitters cause Cl- to move into and K+ to move out of the cell thus creates a situation of hyperpolarisation of the membrane. (These neurotransmitters do not affect movement of Na+.) The increase in membrane potential reaches the axon hillock and raises the voltage required to cause the axon to fire. Since a larger than normal depolarization current is required to generate an action potential these synapses are called inhibitory postsynaptic potentials (IPSP).
Example inhibitory neurotransmitters are: GABA and Glycine

A

Inhibitory synapse and IPSP

147
Q

Neurotransmitter binds to post-synaptic membrane for only a short time (____m). When one molecule leaves another takes its place until all the neurotransmitter in the gap disappears.

A

(1 m)

148
Q

Neurotransmitter can diffuse into the extracellular fluid and taken up by _____.

A

astrocytes

149
Q

Neurotransmitter can be re-uptake into pre-synaptic fibre and re-used. Some of the reuptake neurotransmitter can be broken down by ___________.

A

monoamine oxide (MAO)

150
Q

Neuro- transmitter can be broken down by ______ such as catechol-O-methyltransferase (COMT) and acetylcholinesterase (Ach-ase) and the by- products taken up into the blood.

A

gap enzymes

Physiology (9 decks)

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