Unit 7
a ganglion in the PNS is like a _____ in the CNS
nucleus
what forms myelin sheaths in the CNS
oligodendrocytes
where are beta-1 adrenergic receptors located and what do they respond to
on the heart, respond to epinephrine & norepinephrine binding
Beta-2 adrenergic receptors
reduce intracellular calcium. found on vascular smooth muscle mainly
true or false: Ascending tracts carry sensory information
true - carry it towards brain
T or F: Descending tracts carry efferent signals
true - carry motor info it towards PNS
if you are exposed to a muscarinic ACh receptor antagonist, which of the following symptoms would you expect? a. Increase in heart rate b. Decrease in total peripheral resistance. c. Increase in saliva and other digestive enzyme secretions d. (a) and (b) are correct; (c) is incorrect e. (a), (b), and (c) are all correct
A a is correct because activation of muscarinic ACh receptor would cause a decrease in heart rate, so blocking this receptor would cause an increase in heart rate. b and c are incorrect because peripheral resistance is not at all affected by the parasympathetic system, and because this receptor would normally increase digestive enzyme secretion so this effect would actually be blocked.
You are recording changes in membrane potential in the axon of a sensory afferent. If you note a sudden increase in action potential frequency, which of the following may have happened: a) The intensity of the stimulus has increased b) The duration of the stimulus has increased c) The modality of the stimulus has changed. d) a) and b) are both correct; c) is incorrect e) a), b), and c) are correct
A a is correct because increase in action potential frequency codes for the intensity of the stimulus. b is incorrect because this is coded by the duration that the axon is generating action potentials c is incorrect because this codes for the nature of the stimulus and which receptors are activated
which of the following are parts of the vertebrate peripheral nervous system Afferent Division Efferent Division Somatic Nervous System Autonomic Nervous System Parasympathetic Nervous System Sympathetic Nervous System Brainstem Spinal Cord Thalamus
All except for brainstem, spinal cord, and thalamus
Which of the following statements is/are true: a) Two cells will always exhibit the same intracellular responses after the same neurotransmitter binds to receptors on the cells. b) Sympathetic preganglionic neurons, parasympathetic postganglionic neurons and somatic motor neurons all release ACh. c) Norepinephrine binds to receptors on sympathetic postganglionic cells. d) a) and b) are both correct; c) is incorrect e) a), b), and c) are correct
B a is incorrect because it is the receptor that determines the response c is incorrect because ACh binds to receptors on sympathetic postganglion neurons, and norepinephrine is actually released by these receptors and binds to receptors on the target cell
Acetylcholine is released by many types of neurons. Which type does not typically release ACh a. Somatic motor neurons b. Sympathetic preganglionic neurons c. Sympathetic postganglionic neurons d. Parasympathetic preganglionic neurons e. Parasympathetic postganglionic neurons
B all other types do release ACh
during embryonic development, neural tissue rolls up into a tube, forming a hollow neural tube that becomes the a. brain b. peripheral nervous system c. central nervous system (brain and spinal cord) d. autonomic nervous system e. spinal cord
C
which trait arose first during the evolution of animals? a. ganglia b. central nervous systems c. nervous systems d. neural cords
C
which of the following is true about a dorsal root but NOT about a dorsal horn a. contains neuronal cell bodies b. located within the spinal cord c. is located outside of the spinal cord d. carries incoming sensory info e. contains two separate nuclei
C - dorsal root is located in PNS, but dorsal horn is in gray matter of spinal cord
astrocytes
CNS - help form the blood-brain barrier, take up K+, water & neurotransmitters, a source of neural stem cells, secrete neurotrophic factors, and provide substrates for ATP production
microglia
CNS - modified immune cells, act as scavengers
You are treating a patient with high blood pressure. Which of the following treatments is/are likely to decrease your patient's blood pressure? a. Giving your patient a β1 adrenergic receptor antagonist b. Giving your patient a muscarinic ACh receptor agonist c. Giving your patient an alpha adrenergic receptor agonist d. (a) and (b) are correct; (c) is incorrect e. (a), (b), and (c) are all correct
D a is correct because this would block the B-blockers on the heart, so heart rate would be unable to increase and the force of contractions would also be unable to increase in response to any decrease in blood pressure, so blood pressure would remain in a decreased state. b is correct because binding to the muscarinic ACh receptor on the heart also slows heart rate, so an agonist would activate this receptor as well c is incorrect because the a-adrenergic receptors cause blood vessels to vasoconstrict ==> increase blood pressure
Which of the following pathways contain a ganglion a) Sensory (afferent) pathways into the spinal cord. b) Autonomic (efferent) pathways out of the spinal cord. c) Somatic (efferent) pathways out of the spinal cord d) a) and b) are both correct; c) is incorrect e) a), b), and c) are correct
D a refers to the dorsal root ganglia, b refers to the synapse of the pre- and post-ganglionic neurons in the ganglia out side of the spinal cord c is incorrect because the somatic efferent pathways are inside the spinal cord, and these are not referred to as ganglia since it is part of the CNS then. it would be referred to as neuron
Which of the following animals would you expect to have a cerebellum? a. Bird b. Fish c. Worm d. a) and b) are both correct; c) is incorrect e. a), b), and c) are correct
D bird and fish are both vertebrates, so you would expect them to have a similar development sequence as all other vertebrates, which normally develop a cerebellum a worm is an invertebrate and exhibits primitive brains and nerve cords
where can you find ganglia? a. In the nervous systems of invertebrates b. In autonomic efferent pathways c. In ascending tracts in vertebrates d. (a) and (b) are correct; (c) is incorrect e. (a), (b), and (c) are all correct
D c is incorrect because ascending tracts refers only to the CNS, whereas ganglia are terms used only in reference to the PNS
A β1 receptor antagonist would have which of the following effects: a) It would slow the heart rate b) It would reduce stroke volume c) It would block the generation of action potentials in sympathetic post-ganglionic neurons d) a) and b) are both correct; c) is incorrect e) a), b), and c) are correct
D c is incorrect because these are not B-1 receptors
types of glial cells
In the CNS: astrocytes, ependymal cells, microglia, oligodendrocytes in the PNS: Schwann cells, satellite cells
which of the following structures contain many cell bodies Ventral root Dorsal root ganglion Descending tracts Ascending tracts Autonomic ganglia Dorsal horn Ventral horn Sympathetic chain
Dorsal root ganglion Autonomic ganglia Dorsal horn Ventral horn Sympathetic chain
Which of the following statements is/are true about the blood brain barrier (BBB): a) It is formed by the foot processes of astrocytes that line the brain's capillaries. b) Molecules that can diffuse through plasma membranes can move across the BBB. c) Glucose can move across the BBB using a transport protein. d) a) and b) are both correct; c) is incorrect e) a), b), and c) are correct
E
organization of central and peripheral nervous systems a. Afferent sensory information enters the spinal cord via axons in the dorsal roots b. Efferent autonomic motor information is transmitted over preganglionic axons coursing in the ventral roots c. The dorsal horn of the spinal cord is gray matter that receives synaptic input from nerve fibers with cell bodies in dorsal root ganglia d. (a) and (b) are correct; (c) is incorrect e. (a), (b), and (c) are all correct
E
Which of the following may be found in a nerve? a. Afferent axons b. Efferent axons c. Schwann Cells d) a) and b) are both correct; c) is incorrect e) a), b), and c) are correct
E nerve refers to collection of neurons in the PNS, and it is very common that fibers in the PNS will have axons that carry info to and away from CNS
the blood brain barrier is formed by the processes of myelinating oligodendrocytes, & prevents the movement of many hydrophilic molecules from the circulation into the brain. True or false?
False - this is the correct function of the blood brain barrier but it is astrocytes that form this barrier.
which parts of the brain play a large role in movement coordination? Frontal Lobe Midbrain Basal Ganglia Temporal Lobe Pons Cerebellum
Frontal lobe, basal ganglia, cerebellum
if the dorsal root ganglia from a given spinal segment were removed, sensory info from the associated body parts could not be conveyed to the CNS. True or false?
True - dorsal roots and dorsal root ganglia carry sensory information, and the dorsal root ganglia contain the cell bodies of the sensory neurons. If it were removed, the sensory info subsequently would not be able to be passed along
during brain surgery, a surgeon probes the part of the primary somatosensory cortex that receives sensations from the eye. This causes the region to depolarize. What sensation will this most likely cause? a. light flashing b. a touch to the eyelid c. a touch to the leg d. both a & b
b
duration of the stimulus
coded by duration of action potential train (i.e, continued firing of action potentials in sensory neurons)
location of the stimulus
coded by receptive fields in the nervous system
intensity of the stimulus
coded by the frequency of action potentials
sensory modality
coded by which sensory neurons are activated
activation of alpha-adrenergic receptors increases _______ which leads to _________
contraction of vascular smooth muscle; vasoconstriction
If an individual suffered damage to the brainstem, they would likely experience difficulty with what functions
controlling their breathing, blood pressure, and eye movements
In 2014, a 24-year-old woman was treated at Chinese PLA General Hospital of Jinan Military Area Command in Shandong Province. This where it was first discovered that she did not have a cerebellum. This is due to a rare condition called cerebellar agenesis. Based on this discovery, what would you predict about this woman? a) She has trouble walking steadily. b) As a child, she was a late talker. c) She often feels dizzy. d) All of the above.
d cerebellum plays a very important role in coordinating motor activities across systems => balance => coordination of movement => eye movements important role in integrating information from canals in ears and eye movements so if not functioning properly can cause someone to be dizzy/nauseous
activation of parasympathetic nervous system will _______ heart rate
decrease
ventral roots carry _________ signals
efferent
activation of parasympathetic nervous system will cause ________ in blood vessel diameter
no change
oligodendrocytes
form myelin sheaths in CNS
Schwann cells
form myelin sheaths in PNS and secrete neurotrophic factors
alpha receptors
found on vascular smooth muscle, increase intracellular calcium
Which lobe of the cerebrum contains the primary motor cortex and is the most anterior lobe?
frontal lobe
Response to norepinephrine on Beta-1 receptors
increase, increase intracellular calcium and therefore increase in heart rate and increase in force of heart contraction, this will cause no change in blood vessel diameter though
how does norepinephrine influence mean arterial pressure A. Causes no net change in MAP B. Decreases MAP C. Increases MAP
increases MAP this is because it is released in response to a decrease in blood pressure by the sympathetic nervous system, and then it binds to the a-receptors in the smooth walls of blood vessels and causes the walls to vasoconstrict ==> increase in blood pressure
activation of beta2-adrenergic receptors increases _______ which leads to _________
relaxation of vascular smooth muscle; vasodilation
dorsal roots carry ___________ info
sensory
ependymal cells
separate CNS fluid compartments, and are a source of neural stem cells
satellite cells
support cell bodies in PNS
Which divisions can cause changes in each of the following parameters? Heart rate
sympathetic and parasympathetic S via releasing norepinephrin/epinephrine on the B1 adrenergic receptors P via activating the muscarinic ACh receptors
Which divisions can cause changes in each of the following parameters? mean arterial pressure
sympathetic and parasympathetic this is influenced by heart rate and arterial wall diameter, and heart rate can be influenced by both parasympathetic and sympathetic systems
Which divisions can cause changes in each of the following parameters? heart contractility
sympathetic only parasympathetic response can only slow down the rate of heart contraction, and the force of contraction can only be influenced by beta-1 receptors which are activated by the sympathetic response
Which divisions can cause changes in each of the following parameters? arteriolar radius
sympathetic only there are no muscarinic receptors on arterioles/blood vessels, so only sympathetic responses can cause changes in arterial diameter. The type of receptor (alpha or beta adrenergic) activated determines the change (vasoconstriction or vasodilation)
Which divisions can cause changes in each of the following parameters? stroke volume
sympathetic only this is because only the force of contraction can influence the SV, and the force of contraction can only be increased, it cannot be decreased from baseline value. It is the sympathetic system that causes this change
which part of the vertebrate brain develops from the embryonic diencephalon, and acts as a relay center by processing afferent sensory information and sending it on to the cerebral cortex
thalamus