Unit 4
________ is the term used to describe the crossing over of a tract to the side of the nervous system opposite to where the axons originated. - Relaying - Coordinating - Ascending - Decussation - Descending
- Decussation
Describe the direction of sensory input and motor commands relative to the spinal cord. - Both sensory input and motor commands travel toward the spinal cord. - Sensory input travels toward the spinal cord and motor commands travel away from the spinal cord. - Sensory input travels away from the spinal cord and motor commands travel toward the spinal cord. - Both sensory input and motor commands travel away from the spinal cord
- Sensory input travels toward the spinal cord and motor commands travel away from the spinal cord.
Which neurotransmitter is released at the sympathetic chain ganglia? - acetylcholine - norepinephrine - endorphin - dopamine - All of the answers are correct.
- acetylcholine
A neuron with nicotinic receptors is exposed to acetylcholine. This will not lead to - excitation of the neuron. - binding of the nicotine to the channel. - activation of chemically gated ion channels. - entry of sodium ion. - activation of muscarinic receptors.
- binding of the nicotine to the channel.
A decrease in the autonomic tone of the smooth muscle in a blood vessel would result in - an increase in vessel diameter. - oscillation in vessel diameter. - an increase in blood flow through the vessel. - a decrease in vessel diameter. - both an increase in vessel diameter and an increase in blood flow through the vessel.
- both an increase in vessel diameter and an increase in blood flow through the vessel.
The adrenal medullae secrete - renin. - epinephrine. - norepinephrine. - medullin. - both epinephrine and norepinephrine.
- both epinephrine and norepinephrine.
Control of the diameter of the respiratory passages depends upon - sympathetic stimulation only. - parasympathetic stimulation only. - sensory receptors sensitive to changes in lung ventilation. - somatomotor stimulation only. - both parasympathetic and sympathetic levels of stimulation.
- both parasympathetic and sympathetic levels of stimulation.
The posterior root ganglia mainly contain - synapses. - cell bodies of sensory neurons. - axons of motor neurons. - cell bodies of motor neurons. - axons of sensory neurons.
- cell bodies of sensory neurons.
During sympathetic activation, which of the following would not occur? - elevated heart rate - constriction of pupil - increased sweating - elevated blood glucose - elevated blood pressure
- constriction of pupil
Reflexes that activate muscles on the opposite side of the body as the stimulus are called - collateral. - antilateral. - ipsilateral. - contralateral. - bilateral.
- contralateral.
The ________ reflex complements the flexor reflex by activating contralateral muscles. - crossed extensor - flexor - tendon - stretch - reciprocal
- crossed extensor
The parasympathetic nervous system is especially active during which physiological state(s)? - stress - digestion - exertion - trauma - All of the answers are correct.
- digestion
The dural sinuses are located in the - dural folds. - arachnoid mater. - tentorium cerebelli. - paranasal cavity. - pia mater.
- dural folds.
Preganglionic fibers leave the CNS and then synapse on - motor neurons. - visceral reflex responses. - ganglionic neurons. - sensory neurons. - postganglionic fibers.
- ganglionic neurons.
A viral disease that destroys the neuronal cell bodies of the anterior gray horn will - interfere with communication from one side of the spinal cord to the other. - lead to muscle weakness or paralysis. - mainly interfere with crude touch and temperature sense. - interfere with position sense. - block autonomic regulation.
- lead to muscle weakness or paralysis.
Bill contracts a viral disease that destroys cells in the posterior gray horns in his spinal cord. As a result, which of the following would you expect? - uncontrollable sweating of his feet - problems with moving his arms - problems with moving his legs - loss of sensation in his torso - inability to breathe
- loss of sensation in his torso
The white matter of the spinal cord is mainly - neuroglia. - unmyelinated axons. - myelinated axons. - Schwann cells. - nodes of Ranvier.
- myelinated axons.
Olfactory receptors send axons through the cribriform plate and synapse on neurons in the - olfactory tract. - medulla. - cerebral cortex. - olfactory bulb. - thalamus.
- olfactory bulb.
The cerebral area posterior to the central sulcus is the - insula. - occipital lobe. - parietal lobe. - frontal lobe. - temporal lobe.
- parietal lobe.
What structure is covered by many blood vessels and adheres tightly to the surface of the brain? - dura mater - choroid plexus - arachnoid mater - pia mater - falx cerebelli
- pia mater
A(n) ________ reflex has at least one interneuron placed between the sensory and motor neurons. - motor - integrative - sensory - polysynaptic - monosynaptic
- polysynaptic
The surface of the postcentral gyrus contains the ________ cortex. - primary sensory - visual - primary motor - auditory - olfactory
- primary sensory
Receptors that monitor the position of joints belong to the category called - nociceptors. - proprioceptors. - chemoreceptors. - baroreceptors. - thermoreceptors.
- proprioceptors.
Which of the following is not a function of cerebrospinal fluid? - provides cushioning for delicate neural tissues - provides ATP for impulse transmission - acts as a transport medium for waste products - provides buoyant support for the brain - acts as a transport medium for nutrients
- provides ATP for impulse transmission
The information that is passed from a sensory receptor to the central nervous system is called a - depolarization of a receptor. - perception - motor pathway. - sensation. - transducer.
- sensation.
Visceral reflex arcs can bypass CNS neurons in ________ reflexes. - short - long - both short and long - neither short nor long
- short
The anterior horns of the spinal cord contain mainly - sensory nuclei. - somatic motor nuclei. - sympathetic nuclei. - autonomic motor nuclei. - nerve tracts.
- somatic motor nuclei.
Postganglionic fibers that innervate targets in the body wall or thoracic cavity originate on neurons within - intramural ganglia. - suprarenal ganglia. - collateral ganglia. - sympathetic chain ganglia. - white rami.
- sympathetic chain ganglia.
Which of the following is not one of the special senses? - balance - smell - touch - hearing - taste
- touch
The spinal cord consists of five regions and ________ segments. 5 31 25 The number varies widely among individuals.
31