Chapters 12-13 Flashcards
1) What is the general overall function of the nervous system?
works with the endocrine system to maintain homeostasis, communicates with the body via action potentials, is responsible for thoughts and behaviors, and initiates voluntary movements
2) What makes up the nervous system?
NOT: the vertebral column
3) What are some of the major functions of the nervous system?
Sensory: detect changes in the environment and relays information to the brain and the spinal cord
4) What makes up the central nervous system?
excludes the cranial and spinal nerves, ganglia, and sensory receptors, is the source of thoughts and emotions.
5) What makes up the peripheral nervous system
may be divided into somatic, autonomic, and enteric* nervous system
6) What does the somatic nervous system do?
provides motor signals and conscious control to skeletal muscles
7) What are neurons?
are electrically excitable cells, vary greatly in size, have a prokaryon enriched with the organelles for protein synthesis
8) Which are more numerous for a neuron, dendrites or axons?
axons
9) What makes up a synapse?
a synapse is the site of where two neurons or a neuron: and an effector meet
10) What kind of neuron make up most of the brain?
multipolar
11) What are neuroglia?
compromise about one half of the tissue in the CNS, retain mitotic potential but do not conduct nerve impulses, support and protect neurons.
12) What are astrocytes, what do they do?
they form the blood-brain barrier
13) Which neuroglia cells produce myelin?
oligodendrocytes, schwann cells
14) What is multiple sclerosis (MS)?
disease that results in the destruction of the myelin sheath
15) What makes up gray matter?
consists of neuron cell bodies, neuroglia, and unmyelinated nerve fibers
16) What is true about the electrical potential across a neuron’s plasma membrane?
neurons exhibit differences in electrical voltage across their plasma membrane
17) When ions move across the plasma membrane, what happens?
flow of electrical current, disturb potential
18) What is true about ion channels?
NOT: leakage channels make it more permeable
19) What contributes to the maintenance of a resting membrane potential?
lower plasma membrane permeability to sodium than potassium
20) What are graded potentials?
arise when ion movement causes a minor change in the resting membrane potential
21) What are action potentials
allow an impulse to travel over long or short distances
22) Place the events involved in generating an action potential in the order in which they occur.
132:C
23) Some governments execute convicts using lethal injections that contain high concentrations of KCl. At the cellular level, how does the high concentration of KCl kill the convict?
excess potassium disrupts gradient, no neuron repolarization
24) What is the difference between continuous conduction and salutatory conduction?
continuous conduction is slower than salutary conduction
25) Axons classified as A fibers have what/are what?
they are myelinated, have large diameters, conduct impulses more rapidly
26) An instructor helps a student clean up the pieces of a broken beaker. As they search for glass fragmentsunder the lab bench, the instructor inhales sharply and says, “I just found a piece of glass with my knee.” How
could the instructor determine that her knee was in contact with broken glass rather than with the floor?
the broken glass generated more frequent action potentials than the pressure of the floor, more action potentials in more neurons were activated by the pressure of the glass
27) Do neuron action potentials last longer than muscle fiber action potentials?
NOT neuron action potentials last longer than muscle fiber action potentials
28) What are electrical synapses?
occur when there is direct contact between electrically excitable cells
29) What happens at a chemical synapse?
the pre-synaptic neuron converts an electrical signal into a chemical signal
30) Place the events at a chemical synapse in the order in which they occur.
- action potential arrives at pre-synpatic neurons end bulbs;
- calcium channels bind to vesicles
- vesicles fuse with presynaptic neurons membrane, neurotransmitter exocytosed;
- diffuses across synaptic cleft, neurotransmitter binds to receptors, ***
31) Can the transfer of information at a synapse be bi-directional?
NOT: information transfer at a chemical synaose is bidirectional
32) Two neurotransmitters, epinephrine (E) and serotonin (5-HT), are known to be important in regulation of
mood. Inadequate stimulation of postsynaptic neurons by these neurotransmitters results in depression. Which of
the medications are most likely to increase availability of one of these neurotransmitters and be helpful in treating
depression?
ALL ARE CORRECT
33) What is summation ?
the integration of input into a neuron
34) A postsynaptic neuron receives a greater number and frequency of excitatory signals than inhibitory
signals, but not enough excitatory signals to reach threshold level. What will develop in this neuron?
an EPSP
35) What are the small molecule neurotransmitters?
NOT: substance
36) What does acetylcholine do?
is released from some CNS neurons and most PNS neurons,
is excitatory at skeletal muscle motor end pates,
is inhibitory where the vagus nerve synapses with cardiac fibers
is removed from synapses by the enzyme acetylcholenesterase
37) Which amino acids function as neurotransmitters?
NOT: enkephalin
38) What is true about aspartate?
NOT: aspartate is released by most exitatory neurons in the CNS
39) What are the biogenic amines?
include epinephrine
norephrine
serotonin
dopamine
40) What is norepinephrine?
an epinephrine are also made by the adrenal glands and can be considered hormones