A & P I (Final)
All muscle types will respond to an electrical stimulus because all
muscle cells are ________.
Skeletal muscle is called ________ because it is usually subject to conscious control.
When a skeletal muscle lengthens, its ________ helps resist excessive stretching and subsequent injury to the muscle.
A) troponin-tropomyosin complex
Extensibility refers to the ability of a muscle to stretch.
The sarcoplasmic reticulum is the smooth endoplasmic reticulum of a muscle fiber.
Clinically, dystrophin is the most important noncontractile protein to occur in muscle fibers.
A deficiency of acetylcholine receptors leads to muscle paralysis in myasthenia gravis.
An isometric contraction does not change muscle length.
Which of the following is predominately made up of myosin?
A) G actin
B) The elastic filament
C) The thin filament
D) The thick filament
Which muscle(s) can contract without the need for nervous stimulation?
A) Smooth muscle only
B) Skeletal, smooth and cardiac muscle
C) Skeletal muscle only
D) Smooth and cardiac muscle
80% of the lactic acid produced by skeletal muscle is converted to pyruvic acid by the ________.
B) muscle tissue
C) sarcoplasmic reticulum
Shortening a muscle while it maintains constant tension is called ________.
A) complete tetanus
B) an isotonic contraction
C) an isokinetic contraction
D) an isometric contraction
Which of the following is an accurate comparison of skeletal muscle to smooth muscle?
A) Smooth muscle contracts more rapidly but relaxes more slowly.
B) Smooth muscle contracts more slowly but relaxes more rapidly.
C) Smooth muscle contracts and relaxes more slowly.
D) Smooth muscle depends on a nerve fiber to supply the calcium needed for contraction.
If one nerve stimulus arrives at a muscle fiber so soon that the fiber has only partially relaxed from the previous twitch, the most likely result will be ________.
A) incomplete tetanus
D) flaccid paralysis
To stimulate muscle contraction, acetylcholine is released from the ________ into the synaptic cleft.
A) sarcoplasmic reticulum
B) terminal cisterna
C) synaptic vesicles
The absence or inhibition of acetylcholinesterase at a synapse would lead to ________.
A) muscle wasting
Athletes who train at high altitudes increase their red blood cell count, which increases their oxygen supply during exercise. Increased oxygen supply results in ________.
A) increased glycolysis
B) reduced ATP consumption
C) longer aerobic respiration
D) longer anaerobic fermentation
Cardiac muscle has very little capacity for regeneration because it lacks ________.
A) satellite cells
B) somatic nerve fibers
C) dense bodies
D) an endomysium
Drugs called calcium channel blockers may be used to lower blood pressure by causing arteries to vasodilate. How do you suppose these drugs work?
A) They prevent calcium from entering smooth muscle, thus allowing
the muscle to relax.
B) They prevent calcium from exiting the sarcoplasmic reticulum in skeletal muscle.
C) They stimulate the calcium pump in smooth muscle, thus removing calcium from the calmodulin.
D) They prevent calcium from entering cardiac muscle, thus slowing down the heart rate.
The sarcolemma of a resting muscle fiber is most permeable to ________.
Which of the following is not a characteristic of a muscle cell?
Loss of muscle mass from lack of activity is called ________.
Most neurons have multiple dendrites.
Unipolar neurons have only a single process leading away from the soma.
In the brain, neurons are more abundant than neuroglia.
Which of the following are effectors?
A) Sense organs
What is another name for the autonomic nervous system?
A) Somatic motor division
B) Visceral sensory division
C) Visceral motor division
D) Somatic sensory division
Nerves are ________ of the nervous system.
A) organ systems
The term "nerve fiber" refers to a(n) ________.
C) nerve cell
D) bundle of macromolecules in nerve cells
Most metabolic and regulatory functions in a neuron happen where?
A) The axon hillock
B) The Schwann cell
C) The soma
D) The axon
What is the primary site on a neuron for receiving signals from other neurons?
A) The somas
B) The synaptic knobs
C) The axons
D) The dendrites
In a neuron, the opening of sodium gates typically leads to ________.
A) depolarization of the plasma membrane
B) hyperpolarization of the plasma membrane
C) plasma membrane voltage returning to the resting membrane potential
D) repolarization of the plasma membrane
A myelin sheath is composed primarily of ________.
An inhibitory local potential causes which of the following?
A) Repolarization of the plasma membrane
B) Hyperpolarization of the plasma membrane
C) Drifting of the membrane potential towards the resting membrane potential
D) Neutralization of the plasma membrane
Local potentials are ________, whereas action potentials are ________.
A) nondecremental; decremental
B) self-propagating; local
C) graded; all or none
D) produced by voltage-regulated channels; produced by gated channels
When the voltage of a plasma membrane shifts from +35mV towards 0 mV, the cell is ________.
A) reaching the threshold
During the absolute refractory period which of the following is true?
A) No stimulus of any strength will trigger a new action potential.
B) The neuron fires at its maximum voltage if a stimulus depolarizes the neuron to threshold.
C) The signal grows weaker with distance.
D) If a neuron reaches threshold, the action potential goes to completion.
A cholinergic synapse uses ________ as its neurotransmitter.
Parkinson disease is a progressive loss of motor function due to the degeneration of specific neurons. These neurons secrete an inhibitory neurotransmitter that prevents excessive activity in motor centers of the brain. What neurotransmitter is this?
While both systems maintain homeostasis, how does the nervous system differ from the endocrine system?
A) The nervous system releases hormones into the blood, while the
endocrine system releases neurotransmitters between cells.
B) The nervous system releases neurotransmitters into the blood, while the endocrine system releases hormones between cells.
C) The nervous system releases hormones between cells, while the endocrine system releases neurotransmitters into the blood.
D) The nervous system releases neurotransmitters between cells, while the endocrine system releases hormones into the blood.
Ascending signals in the spinal cord travel via gray matter, while descending signals travel via white matter.
Each portion of the spinal cord, from which a spinal nerve emerges, is called a "segment" of the cord.
A ganglion is a swelling along a nerve containing the cell bodies of peripheral neurons.
Voluntary motor signals typically begin in an upper motor neuron in the thalamus.
Posterior root ganglia contain somas of unipolar neurons.
) The tendon reflex is the inhibition of a muscle's contraction that occurs when its tendon is excessively stretched.
The signals that control your handwriting travel down the spinal cord in the ________ tracts.
C) medial vestibulospinal
Which of the following sensory functions involves neurons in the posterior root ganglion?
Which of the following is not considered a region of the spinal cord?
Which of the following fractures would be the least likely to cause a spinal cord injury?
A) A fracture of vertebra C2
B) A fracture of vertebra L4
C) A fracture of vertebra C6
D) A fracture of vertebra T12
The middle layer of the meninges is called the ________.
A) arachnoid mater
B) pia mater
C) gray matter
D) dura mater
Voluntary motor impulses leave the spinal cord via the ________ of gray matter.
A) posterior column
B) lateral horn
C) anterior horn
D) posterior horn
Cerebrospinal fluid fills the space between the ________.
A) dural sheath and dura mater
B) arachnoid mater and pia mater
C) dura mater and pia mater
D) dura mater and arachnoid mater
Which of the following structures is the richest in lipid content?
A) White matter
B) Gray matter
C) Dura mater
D) Pia mater
Which of the following is contained within gray matter?
A) Neurosomas, dendrites, and proximal parts of axons of neurons
B) Glial cells, axons of motor neurons, and Schwann cells
C) Glial cells only
D) Glial cells and myelinated fibers
Motor commands are carried by ________ from the brain along the spinal cord.
A) spinal nerves
B) both anterior and posterior roots
C) cranial nerves
D) descending tracts
Eyes and ears are innervated by ________ fibers.
Which of the following is comprised of anterior rami from C5-T1?
A) Coccygeal plexus
B) Sacral plexus
C) Lumbar plexus
D) Brachial plexus
A nurse pricks your finger to type your blood. You flinch at the pain, pulling your hand back. This is called the ________ reflex.
A) flexor (withdrawal)
B) crossed extension
You go to the movies after a long day and you begin to nod off as soon as the movie starts. Your head starts to lower a little, but a reflex causes your head to rise. This is called the ________ reflex.
A) crossed extension
B) stretch (myotatic)
The cerebellum exhibits folds called gyri separated by grooves called sulci.
The blood-brain barrier (BBB) helps prevent hemorrhages in the nervous tissue of the brain.
The amygdala, hippocampus and hypothalamus are involved in such feelings as love, anger, fear, pleasure, and pain.
The right and left cerebral hemispheres are separated from each other by ________.
A) many sulci
B) many gyri
C) the corpus callosum
D) the longitudinal fissure
From superficial to deep, the meninges occur in which order?
A) Pia mater, arachnoid, dura mater
B) Dura mater, pia mater, arachnoid
C) Pia mater, dura mater, arachnoid
D) Dura mater, arachnoid, pia mater
The blood-brain barrier (BBB) is most permeable to which of the following?
A) Glucose and oxygen
C) Sodium, potassium, and chloride
D) Platelets, white blood cells, and red blood cells
Which structures create the blood brain barrier (BBB)?
A) Tight junctions between endothelial cells that form the
B) Gap junctions between endothelial cells that form the capillary walls
C) Gap junctions between ependymal cells and endothelial cells that form the capillary walls
D) Desmosomes and tight junctions between astrocytes and ependymal cells that form the capillary walls
A patient is experiencing a high fever, stiff neck, drowsiness, and intense headaches. A spinal tap showed bacteria and white blood cells in the cerebrospinal fluid (CSF). This individual most likely has what condition?
A) Parkinson disease
B) A stroke
Where are the cardiac, vasomotor, and respiratory centers found?
B) Medulla oblongata
C) Spinal cord
The reticular formation is a web of ________ scattered throughout the ________.
A) neurosomas; hypothalamus
B) nerves; white matter in the cerebrum
C) gray matter; cerebrum
D) gray matter; brainstem
There are no cranial nerves associated with which part of the brain?
B) Medulla oblongata
Nearly all the somatosensory input to the cerebrum passes by way of synapses in which region of the brain?
Sex drive, body temperature, and food and water intake are regulated by which part of the brain?
B) Pineal gland
C) Pituitary gland
D) Limbic system
Where are the hippocampus and amygdala found?
A) Limbic system
B) Basal nuclei
C) Cerebral cortex
D) Medulla oblongata
Short-term memory is associated with the ________, whereas long-term memory is associated with the ________.
A) cerebral cortex; amygdala
B) hippocampus; midbrain
C) hippocampus; cerebral cortex
D) cerebral cortex; hippocampus
The pyramidal cells of the precentral gyrus are called ________ neurons.
A) lower motor
D) upper motor
The autonomic nervous system is composed of ganglia in the central nervous system and ganglia in the periphery.
Most autonomic efferent pathways involve one neuron.
The parasympathetic division stimulates digestion.
) The adrenal medulla is a modified sympathetic ganglion.
Fibers of the vagus nerve end very near or within their target organs.
All sympathetic postganglionic adrenergic fibers secrete adrenaline.
All autonomic output originates in the central nervous system.
The autonomic nervous system controls all of the following except the ________.
A) skeletal muscle in the rectus abdominis
B) parotid salivary gland
C) adrenal gland
D) cardiac muscle in the right atrium
The background rate of sympathetic and parasympathetic activity is called ________.
A) visceral tone
B) visceral motor activity
C) autonomic reflex arc activity
D) autonomic tone
In response to high blood pressure, stretch receptors called ________ in the walls of arteries carrying blood to the head, will trigger a reflex that causes the heart to ________ its beats per minute.
A) chemoreceptors; increase
B) baroreceptors; decrease
C) proprioceptors; decrease
D) proprioceptors; increase
The motor pathway of the autonomic nervous system usually involves ________ neurons.
Preganglionic fibers run from the ________ to the ________.
A) posterior root ganglia; gray matter
B) posterior root ganglia; autonomic ganglia
C) gray matter; autonomic ganglia
D) autonomic ganglia; visceral effectors
The adrenal medulla secretes mostly ________.
A) norepinephrine (noradrenaline)
C) acetylcholine (ACh)
D) epinephrine (adrenaline)
The solar plexus is used as a name for the ________.
A) the celiac and mesenteric ganglia
B) sympathetic nerve route
C) carotid plexus
D) splanchic nerves
Which of the following is not a characteristic of the enteric nervous system?
A) It does not arise from the brainstem.
B) It innervates smooth muscle.
C) Its reflex arcs are associated with the spinal cord.
D) It innervates glands.
The parasympathetic division arises from the ________ regions of the spinal cord.
A) sacral and lumbar
B) brain and sacral
C) brain, sacral, and coccygeal
D) brain, lumbar, sacral, and coccygeal
Olfaction results from the stimulation of chemoreceptors
Taste signals travel from the tongue through the facial and glossopharyngeal nerves.
The ossicles belong to the middle ear
Light falling on the retina is absorbed by rhodopsin and photopsin in the pigment epithelium.
Vitamin A is necessary for the synthesis of rhodopsin.
Changes in blood pressure are detected by ________ in certain arteries.
Pain, heat, and cold are detected by ________.
A) tactile corpuscles
B) tactile (Meissner) discs
C) end (Krause) bulbs
D) free nerve endings
In a taste bud, which cell produces a receptor potential?
A) Sensory nerve fibers
B) Taste hairs
C) Supporting cells
D) Gustatory cells