Unit 3 Flashcards
(121 cards)
1
Q
- Identify this general part of a neuron. It is the receiving area of a neuron.
A
dendrite
2
Q
- This arrow is pointing to that entire middle section of the cell that
contains a majority of the organelles. What is it generally called?
A
Cell body or soma
3
Q
- This arrow is pointing to the center structure inside the cell where DNA is housed. What is it?
A
Nucleus
4
Q
- This arrow is pointing towards several bundles of white material that are wrapped around a thin gray structure. These bundles function as insulation. What are they collectively called?
A
Myelin
5
Q
- This line is pointing towards a specialized area of the neuron that
generates actions potentials when appropriately stimulated. What is it called?
A
Axon Hillock
6
Q
- This arrow is pointing to the long, thin, gray cellular extension inside
the white bundles. This part of a neuron conducts or transmits action
potentials from the cell body to where neurotransmitters or neuromodulators are released. What is it?
A
Axon
7
Q
- This arrow is pointing towards the bulbous end of a neuron where it interfaces with another cell by releasing neurotransmitters or neuromodulators. What is that part generally called?
A
Axon terminal
8
Q
- This arrow is pointing towards the gap between the top neuron and
the bottom neuron in that zoomed-in view. What is that gap called?
A
Synaptic cleft
9
Q
- This arrow is pointing towards the receiving area of the next neuron. What is that part called?
A
Dendrite
10
Q
This division of the nervous system consists of the brain and spinal cord only.
A
CNS - Central Nervous System
11
Q
This branch of the nervous system contains only sensory (afferent) neurons and motor (efferent) neurons.
A
PNS - Peripheral Nervous System
12
Q
This branch of the nervous system is a network of neurons that lines the walls of the digestive tract. We will talk about it more towards the end of the course.
A
Enteric Nervous System
13
Q
As you learned in your prerequisite Anatomy class, nerves are bundles of many separate axons. Nerves that carry afferent signals only from the periphery to the central nervous system are called __________.
A
Sensory Nerves
14
Q
Nerves that carry only efferent signals from the central nervous
system out to skeletal muscles are called _________.
A
motor nerves
15
Q
Nerves that carry both sensory and motor signals are called ________.
A
mixed nerves
16
Q
This general type of cell is the functional unit of the nervous system.
A
neuron
17
Q
For this specific type of neuron, all its components (dendrites, cell body, axon, axon terminals) are contained completely within the central nervous system. These cells are used to spread information from one place in the central nervous system to another.
A
interneuron
18
Q
This general kind of cell in the nervous system gets its name from the Latin word for “glue.” These cells are crucial for providing support for neurons and also forming insulation around their axons.
A
Glial cells
19
Q
These specific cells form the myelin sheath in the central nervous system. As a part of their name implies, they can typically myelinate “a few” separate neurons with their arm-like extensions.
A
Oligodendrocytes
Oligo = a few
20
Q
These specific cells form the myelin sheath in the peripheral nervous system. They can only wrap themselves around one axon.
A
Schwann cell / neurolemmocyte
21
Q
The spaces on the axon that are tiny gaps in the myelin sheath are called __________.
A
Nodes of ranvier / neurofibril nodes
22
Q
These glial cells have a highly branched, star-like appearance and have many jobs, including take up and release of chemicals, providing neurons with substrates for ATP production, and help to maintain homeostasis in the CNS extracellular fluid. These cells are also important for forming the blood-brain-barrier.
A
astrocytes
23
Q
These specialized glial cells are the part of the immune system that resides in the CNS. They remove damaged cells and destroy foreign invaders.
A
Microglia
24
Q
These specific cells create a semi permeable layer that separates the fluid compartments of the CNS (ventricles) from the actual brain tissue.
A
ependymal cells
25
A/an _____ is a rapid change in membrane potential is an “all-or-none” phenomenon and transmits an electrical signal down the axon. This phenomenon is also known as a “spike”.
action potential
26
This is a general term for changes in membrane potential in the dendrites or cell body that vary in strength and can be either positive or negative. They also travel very short distances and lose strength rapidly. However, multiple ones in close spatial proximity or close in time add together to travel further or last longer.
graded potential
27
Graded potential is a general term with two specific sub-types. A(n) _____ is the sub-type that describes a small depolarization.
EPSP - Excitatory post-synaptic potential
28
A sub-type of graded potential that is defined by a small hyperpolarization. (Hint: See pp. 260 - 261).
IPSP - Inhibitory post-synaptic potential
29
What is the typical resting membrane potential for a neuron in
millivolts?
-70 mV
30
If the sum of all graded potentials at the axon hillock surpasses a
particular membrane potential called the __________ , the neuron will
generate or “fire” an action potential.
threshold voltage
31
At what membrane potential (in millivolts) will an action potential be
generated in a typical neuron?
-55 mV
32
When a neuron generates an action potential, it will rapidly depolarize
due to the influx of a few of these specific ions.
Na+
33
During the depolarization phase of an action potential, channels for this specific ion will be slow to open and achieve maximum
permeability just after the membrane reaches its maximum potential.
K+
34
The repolarization of the membrane during an action potential is
mostly due to efflux of a few of these specific ions.
K+
35
The phase of the action potential when the cell’s membrane potential dips below its resting level.
hyperpolarization
36
When a neuron is in the process of generating an action potential (including the depolarization and repolarization phases), it cannot fire a second action potential, no matter how much additional stimulation it receives. This period is called the ______________.
absolute refractory period
37
As the neuron’s membrane potential is slowly returning to the resting level from a hyperpolarized state, it CAN fire a second action potential IF the next stimulus is larger than normal. This period is called the ______________.
relative refractory period
38
______ is the specific term for an action potential moving rapidly down a myelinated axon.
saltatory conduction
39
When an action potential reaches the axon terminal, voltage-gated
____ channels will open and this ion will influx.
Ca2+
40
Calcium moves into the cell, _______ will fuse with the plasma membrane and release whatever signal molecule (a
neurocrine) they contain.
synaptic vessicles
41
A signal molecule that is released by a neuron into the synaptic cleft
could be a neuromodulator or a ___________.
neurotransmitter
42
A signal molecule that is released by a neuron into the circulatory
system (blood) is called a __________.
neurhormone
43
. If a signal molecule is released into a synaptic cleft, it will bind with
receptors on post-synaptic membrane. Eventually the effect of that
signal molecule will be turned off by several mechanisms. In some
cases, neurotransmitters are degraded by ______ in the synaptic cleft.
enzymes
44
In other cases, neurotransmitters will be transported back into the
neuron that secreted them for recycling or into a nearby glial cell for
degradation. This process is called _______________.
reuptake
45
This general category of neurotransmitters includes norepinephrine,
dopamine, serotonin, and histamine.
amines
46
This general neurotransmitter category includes adenosine.
purine
47
This is the only gas shown in this table that acts as a neurotransmitter.
nitric oxide
48
This specific neurotransmitter has two types of receptors – nicotinic
and muscarinic.
aceytlcholine
49
Many antipsychotic drugs are antagonists for this neurotransmitter.
Drugs of abuse are also typically agonists of this neurotransmitter.
dopamine
50
Molecules such as glutamate, GABA, and glycine belong to this general family of neurotransmitters.
amino acids
51
Alcohol, barbiturates, and benzodiazapines potentiate the effects of
this neurotransmitter.
GABA
52
Curare and alpha-bungarotoxin will block the action of these
acetylecholine receptors, so avoid being shot by poison darts!
Nicotinic
53
Atropine will block the action of these acetylcholine receptors. This is
why atropine is used to elevate heart rate during anesthesia.
muscarinic
54
The efferent branch of the peripheral nervous system can be subdivided into two general types of neurons. More specifically, the ____ control smooth muscle, cardiac muscle, many glands, and some adipose tissue.
Autonomic neurons
55
These efferent peripheral nervous system neurons always control
skeletal muscles.
Somatic motor neurons
56
Autonomic neurons can also be broken up into two branches that are
distinguished best by the type of situation in which they are most
active. This branch is dominant in stressful or active situations and is
often linked to the “fight or flight” response.
Sympathetic branch
57
This branch of the autonomic nervous system is more active if you are
resting quietly after a meal or during the quiet activities of day-to-day
living. It is often linked to the phrase “rest and digest.”
Parasympathetic branch
58
All autonomic neural circuits consist of two neurons connected in
series between the central nervous system and the effector. The first
neuron, called the ________, has its cell body within the central
nervous system.
Preganglionic neuron
59
The next neuron in the circuit has its cell body outside the central
nervous system (in an autonomic ganglion) and projects to an effector
organ or target tissue (e.g., the heart).
Postganglionic neuron
60
The preganglionic neurons of both the parasympathetic and
sympathetic branches secrete this neurotransmitter.
Acetylcholine
61
The postganglionic neurons of the sympathetic nervous system secrete
this neurotransmitter onto effector cells (e.g., the heart).
Norepinephrine
62
The postganglionic neurons of the parasympathetic nervous system
secrete this neurotransmitter onto effector cells (e.g., the heart).
Acetylcholine
63
The chromaffin cells of the ________ are modified postganglionic sympathetic neurons that secrete their neurohormone into the blood stream.
Adrenal medulla
64
The neurohormone secreted by the structure named in Question 10 is called ____________.
Epinephrine
65
Input from the _________ nervous system to the lungs will result in
airway (bronchiole) dilation to allow more air into the lungs during
times of physical or emotional stress.
Sympathetic
66
Input from the _________ nervous system will cause bronchiole
constriction because demand on the lungs is less during times of rest.
Parasympathetic
67
Heart rate and contraction force are increased by _______ nervous system signaling to increase delivery of O2 and nutrients to the body in times of stress.
Sympathetic
68
Signaling by the _________ nervous system will decrease heart rate
during times of rest.
Parasympathetic
69
The control of bronchiole diameter and heart rate use input from both
the sympathetic and parasympathetic nervous systems. These are
both prime examples of _________ control systems that we learned
about back at the end of Chapter 6 (Unit 2).
Antagonistic
70
_______ nervous system input to the adrenal medulla will increase the
secretion of catecholamines, such as epinephrine, into the blood.
Sympathetic
71
_______ nervous system input to adipose tissue will increase fat
breakdown to mobilize energy stores for increased cellular respiration.
Sympathetic
72
_______ nervous system input to the kidneys will increase rennin
secretion, which is very important for the retention of Na+ and
elevation of blood pressure (more on these processes in Unit 5).
Sympathetic
73
Only one branch of the autonomic nervous
system controls target tissue function. It is the amount of signaling by
that one system that determines what the effector organ actually
does. These are prime examples of ________ control systems that we
learned about back at the end of Chapter 6 (Unit 2).
Tonic
74
When the pupils receive _________ nervous system input they dilate
to bring more light (i.e., visual information) into the eyes. This
shouldn’t be shocking, since vision is the primary sense for humans.
Sympathetic
75
When the pupils receive _________ nervous system input they
constrict back to their baseline diameter and therefore allow less light
into the eyes.
Parasympathetic
76
It’s probably not a great idea to devote a lot of energy to digestion
during times of physical or emotional stress, right? Well, you should
not be surprised to find out that _______ nervous system input
decreases digestive motility and secretion.
Sympathetic
77
By contrast, __________ nervous system input will increase digestive motility and secretion. Hence the classic “rest and digest” phrase that typically describes this autonomic branch.
Parasympathetic
78
Preganglionic neurons of both the sympathetic and parasympathetic
nervous system release acetylcholine onto _________ receptors
(specific name) on their postganglionic neurons.
NN nicotinic
79
Somatic motor neurons always release acetylcholine onto ______
receptors located on the motor endplate of skeletal muscle cells.
NM nicotinic
80
Which of the four major categories of receptors discussed in Chapter 6
(Unit 2) do those receptors from Questions 25 and 26 fall into?
Receptor (ion) channels
81
Postganglionic parasympathetic neurons also release acetylcholine
onto their target cells (e.g., the heart). However, this time, the
acetylcholine binds to _______ receptors (specific name).
Muscarinic
82
Which of the four major categories of receptors discussed in Chapter 6 (Unit 2) do those receptors from Question 28 fall into?
G-protein coupled receptors
83
This subtype of adrenergic receptors is more sensitive to epinephrine
than norepinephrine and is found in certain blood vessels and smooth
muscle of some organs.
Beta-2
84
This subtype of adrenergic receptor also has a higher affinity for
norepinephrine than epinephrine, but these are predominantly found
in the digestive tract and pancreas.
Alpha-2
85
This subtype of adrenergic receptors binds equally to norepinephrine
and epinephrine and is found primarily on the heart and kidneys.
Beta-1
86
This subtype of adrenergic receptor is more sensitive to
norepinephrine than epinephrine and is found in adipose tissue.
Beta-3
87
This subtype of adrenergic receptor has a higher affinity for
norepinephrine than epinephrine and is the most common on
sympathetic target tissues.
Alpha-1
88
This type of muscle tissue is found only in the heart and helps to pump blood through the circulatory system.
Cardiac muscle tissue
89
This type of muscle tissue is primarily found in the internal organs and tubes, such as the stomach, urinary bladder, and blood vessels.
Smooth muscle tissue
90
All of the adrenergic receptors from qualify as
______, which was one of the four major categories of receptors
introduced in Chapter 6 (Unit 2).
G-protein coupled receptors
91
This type of muscle tissue is attached to the bones of the skeleton, enabling these muscles to control body movement.
Skeletal muscle tissue
92
When this general kind of skeletal muscle contracts, it brings the
centers of two bones closer together.
Flexor
93
When this general kind of skeletal muscle contracts, the centers of two bones move away from each other.
Extensor
94
These muscles are largely fatigue resistant and used for standing and
walking.
Fast-twitch oxidative glycolytic
95
These muscle fibers have the least mitochondria and the lowest
capillary density.
Fast-twitch glycolytic
96
In the left diagram above, #7 is pointing at the _____, which attaches a skeletal muscle to a bone.
Tendon
97
These muscle fibers can be thought of as a hybrid between those that develop maximum tension the fastest and those that develop
maximum tension the slowest.
Fast-twitch oxidative glycolytic
98
These muscle fibers make up red muscle and get that color due to large
stores of the protein myoglobin, which stores excess oxygen for long
term use.
Slow-twitch oxidative
99
In the left diagram above, #5 is pointing at a bundle of muscle fibers, also known a(n) _______.
Muscle fascicle
100
These muscle fibers make up white muscle, are quick to twitch, but are
also easily fatigued.
Fast-twitch glycolytic
101
In the left diagram above, #3 is pointing at two layers of _______ which surrounds and protects the entire skeletal muscle.
Connective tissue
102
These muscle fibers are the most resistant to fatigue, largely because
they have many mitochondria, very dense capillaries, and get their ATP
from oxidative or aerobic respiration.
Slow-twitch oxidative
103
In the left diagram above, #4 is pointing at a single ______, which is the functional unit of the whole muscle.
Skeletal muscle cell (fiber)
104
The Ca2+ ions released into the sarcoplasm will continue to stimulate a
muscle contraction. However, you do not want contraction to last
forever. So, Ca2+ ions are actively returned to the sarcoplasmic
reticulum by carrier proteins called __________ when stimulation from
the somatic motor neuron ceases.
Ca2+-ATPases
105
In the right diagram above, #6 is printed on the _______, which is the
specific term for the muscle cell plasma membrane.
Sarcolemma
106
When myosin is finished with its flexing and pulling action, it will bind one molecule of ______ to detach from actin and cock back for another cycle.
ATP
107
In the right diagram above, #2 is pointing at tunnels that penetrate deep into the skeletal muscle cell, allowing action potentials to activate all sarcomeres simultaneously.
Transverse tubules
108
When the protein named in the previous question binds to actin, it will
flex its head towards the M-line of the sarcomere, pulling the entire
thin filament in the same direction, and ultimately contracting the
muscle. This flexing and pulling action is called the _______.
Power stroke
109
Displacement of tropomyosin allows a motor protein on the thick
filament called _______ to bind to actin on the thin filament.
Myosin
110
In the right diagram above, #5 is pointing at a bundle of thick and thin filaments, collectively known as a(n) ________.
Myofibril
111
The Ca2+ ions diffuse to the nearest sarcomere and bind to _______,
which becomes activated and moves a protein called tropomyosin.
Troponin
112
In the right diagram above, #1 is pointing at the ______, which is an
intracellular organelle that releases Ca2+ ions into the sarcoplasm when the muscle cell is activated by an action potential.
Sarcoplasmic reticulum
113
The receptors mentioned in the previous question are mechanically
linked to Ca2+ channels on the sarcoplasmic reticulum. These channels
are called ___________ receptors and they release Ca2+ into the
sarcoplasm.
Ryanodine (RyR)
114
The general term for the site where a somatic motor neuron contacts a skeletal muscle fiber is the ___________.
Neuromuscular junction
115
As the electrical signal mentioned in the previous question moves
down the transverse tubules, it will eventually trigger ______
receptors, which are voltage-sensitive proteins.
Dihydropyridine (DHP)
116
The specialized part of a skeletal muscle cell at the neuromuscular junction is called the ________.
Motor end plate
117
These depolarizations mentioned in the previous question always
reach threshold and initiate an all-or-nothing __________ that races
across the sarcolemma and down the nearest transverse tubule.
End plate potential (EPP)
118
The neurotransmitter released by a somatic motor neuron onto a
skeletal muscle cell is _________.
Acetylcholine
119
The specific kind of receptors that receive acetylcholine at neuromuscular junctions are __________.
Nm Nicotinic
120
When the receptors in the previous question are triggered, a large amount of this ion will influx through them.
Na+
121
When the NM nicotinic receptors are triggered, a small amount of
this ion will efflux through them.
K+
