Which of the following represents the correct order of the layers of the epidermis from the deepest to the most superficial?
This is the dermal layer closest to the epidermis
The epidermal layer that is present in the nail bed and the nail matrix is the
surrounds each muscle fiber
Endomysium is a delicate network of loose connective tissue that
2, 3, 1, 4
List the following structures in order from smallest to largest. (1) muscle fiber (2) myofilament (3) myofibril (4) muscle fasciculus
Which of the following connective tissue layers is outside all the others?
globular (G) actin
Which of the following is part of a thin myofilament?
has a calcium-binding site
Which of the following is composed of myosin molecules?
The active sites to which cross-bridges attach are found on the
ATPase is found in
The region of the sarcomere that contains both actin and myosin myofilaments is called the
Both actin and myosin myofilaments shorten during contraction. (T/F)
contain strands of fibrous actin
5, 3, 2, 4, 1
Arrange the events of synaptic transmission in correct sequence. (1) sodium ions diffuse into the cell and cause a local potential (2) neurotransmitter binds with receptor on postsynaptic cell (3) neurotransmitter diffuses across the synaptic cleft (4) membrane permeability to sodium ions on postsynaptic cell increases (5) action potential causes release of neurotransmitter
voltage-gated ion channels
Channels that open or close in response to changes in the electrical charge or voltage across the plasma membrane are called
Synaptic vesicles in the neuromuscular junction contain
continuous stimulation of the postsynaptic membrane
Lack of acetylcholinesterase in the synaptic cleft would result in
conduct action potentials deep into the muscle cell
stores calcium ions
The sarcoplasmic reticulum
1, 3, 4, 2, 5
Arrange the following list of biochemical events in the correct sequence. (1) An action potential is conducted deep into the muscle fiber by the T tubule. (2) Calcium ions bind to troponin. (3) The membranes of the sarcoplasmic reticulum become more permeable to calcium ions. (4) Calcium ions diffuse into the sarcoplasm around the myofibril. (5) The troponin-tropomyosin complex moves exposing active sites.
Which of the following would occur as a result of a single muscle contraction?
a single muscle fiber and a single motor unit
Which of the following will respond to a threshold stimulus with an all-or-none contraction?
A condition in which stimuli occur so rapidly that there are no intervening relaxations between contractions is called
the muscle produces increasing tension as it shortens
Concentric contractions occur when
depletion of ATP reserves
Which of the following would contribute to muscular fatigue in the muscle fiber?
Schwann cells form a myelin sheath around only one axon, while oligodendrocytes extend processes to surround several axons at once.
Schwann cells differ from oligodendrocytes in which of the following ways?
both anaerobic and aerobic respiration
Which type of respiration produces ATP molecules?
Which type of respiration occurs in the mitochondria?
inability of the muscle fiber to respond to nervous stimulation
Curare blocks acetylcholine receptors at the motor end plate. This would result in
conveys action potentials to the CNS
The sensory (afferent) division of the peripheral nervous system
Cell bodies of the peripheral nervous system are located in
There are _____ pairs of cranial nerves and _____ pairs of spinal nerves
cell bodies or soma
Protein synthesis in neurons occurs in
areas of rough endoplasmic reticulum
Nissl bodies are
are the input part of the neuron
Neuroglia produce action potentials for skeletal muscles (T/F)
A neuroglial cell that is a major component of the blood-brain barrier is the
Overproduction of cerebrospinal fluid could be the result of overactivity of the
are phagocytic cells in the CNS
Multiple sclerosis is a neurological disorder in which myelin sheaths in the CNS are destroyed. Which of the following neuroglial cells is being damaged in multiple sclerosis?
Mr. Miller has been hospitalized for the flu. The flu virus increases membrane permeability to potassium. You would expect his cells to
A nerve, which causes the smooth muscle of a blood vessel wall to constrict, contains __________ neurons
3, 1, 4, 2
Arrange the following in correct sequence: (1) autonomic ganglia and ganglionic synapse (2) synapse with target tissues (3) preganglionic neuron (4) postganglionic neuron
short postganglionic axons near the organs they innervate
The parasympathetic nervous system is characterized by
When acetylcholine binds with nicotinic receptors, the response is
parasympathetic blocking agent
Atropine causes the pupil of the eye to dilate by blocking the effect of muscarinic receptors. This means atropine is a(n)
increased parasympathetic responses and increased sympathetic responses
When a person consumes a substantial amount of nicotine, the response is
muscarinic blocking agent
Acetylcholine will cause the pupil of the eye to constrict. A drug acts on receptors for acetylcholine to cause the pupils of the eye to dilate. Nicotine does not bind to receptors in smooth muscle cells of the iris. Therefore, the drug which causes the pupils to dilate is a
epinephrine and norepinephrine
Sympathetic stimulation of the postganglionic cells of the adrenal medulla causes the release of
interfere with the ability to respond to neurotransmitter.
Damage to a postsynaptic membrane would
Gap junctions are functional __________ synapses
spatial summation occurs
When two action potentials arrive simultaneously at two different presynaptic terminals that synapse with the same postsynaptic neuron
Initiating the withdrawal reflex in both legs at the same time would cause one to
The posterior horn of the cord contains the cell bodies of motor neurons (T/F)
affect sensory projection to the cerebral cortex
Injury to the thalamus would
Which of the following cranial nerves is exclusively sensory?
cutaneous sensations on the opposite side of the body below the level of injury
Lesions on one side of the spinal cord cut the lateral spinothalamic tract of the anterolateral system and eliminate
Specialized muscle fibers associated with detection of muscle length are
maintains control of unconscious movements
The extrapyramidal system (indirect pathway)
the third and fourth ventricle
The cerebral aqueduct connects
A conscious awareness of stimuli received by sensory receptors