BIOL 2130 Mastering- Ch. 7
A graded potential is also known as a nerve impulse.
False
The term central nervous system refers to the ________.
brain and spinal cord
The midbrain, pons, and medulla oblongata are housed in the ________.
brain stem
Which ion causes neurotransmitter vesicles to fuse with the axon's membrane during the conduction of a nerve impulse from one neuron to the next?
calcium
Ganglia are collections of ________.
cell bodies
The nervous system is structurally subdivided into two systems: ________ nervous system and ________ nervous system.
central; peripheral
Loss of muscle coordination results from damage to the ________.
cerebellum
The brain dysfunction where blood supply to a region (or regions) of the brain is blocked and vital brain tissue dies, as by a blood clot or a ruptured blood vessel, is called ________.
cerebrovascular accident (CVA), or stroke
Which one of the following is the correct sequence of nerves that exit the spinal cord, from superior to inferior?
cervical spinal nerves, thoracic spinal nerves, lumbar spinal nerves, sacral spinal nerves
Which spinal plexus gives rise to the phrenic nerve, and what organ does this nerve supply?
cervical; diaphragm
What produces cerebrospinal fluid (CSF)?
choroid plexus
Medulla Oblongata
contains centers that control heart rate, blood pressure, breathing, swallowing, and vomiting
Cerebrospinal fluid circulates through all of the following EXCEPT ________.
corpus callous
Which cranial nerves control eye movement?
cranial nerve III, IV, VI (3, 4, 5)
What part of a neuron receives signals and sends a message to the cell body?
dendrite
The neuron processes that normally receive incoming stimuli are called ________.
dendrites
Which one of the following statements about aging is most accurate?
despite some neuronal loss, an unlimited number of neural pathways are available and ready to be developed; therefore, additional learning can occur throughout life
The thalamus, hypothalamus, and epithalamus collectively constitute the:
dicephalon (inter brain)
Bipolar neurons are commonly ________.
found in the eye and nose
Pituitary gland
gland that hangs from the hypothalamus
Midbrain
includes the cerebral peduncles and the corpora quadrigemina
Epithalamus
includes the pineal gland and choroid plexus of the third ventricle
Why is white matter "white"?
it contains a high concentration of myelin
Which of these is a deep pressure receptor?
lamellar corpuscle
The fissure in the brain that separates the two cerebral hemispheres is called the ________.
longitudinal fissure
The cell bodies of the ________ neurons are always located within the CNS.
motor
Impulse conduction is fastest in neurons that are ________.
myelinated
The gaps between Schwann cells found at regular intervals in peripheral system neurons are called ________.
nodes of Ranvier
The hypothalamus regulates the ________.
pituitary gland
During repolarization, ________ ions are pumped out of the cell.
potassium
What part of the brain do we use when initiating skeletal muscle movement?
primary motor area
Sensory receptors located in muscles and tendons are termed ________.
proprioceptors
Each spinal nerve branches into a ventral and dorsal ________.
ramus
Part complete Each spinal nerve divides into a dorsal and a ventral ________.
ramus
Which of these lists the components of a reflex arc in the correct sequence?
receptor afferent neuron control center efferent neuron effector
Hypothalamus
regulates body temperature, water balance, and metabolism
Thalamus
relay station for sensory impulses passing to the sensory cortex
________ cells form the myelin sheaths around nerve fibers in the PNS.
schwann
Which of the following neurons is classified as a unipolar neuron?
sensory neuron
What is the first event of an action potential?
sodium gates open and the membrane depolarizes
Which division of the peripheral nervous system activates skeletal muscles?
somatic nervous system
Preparing the body for the "fight-or-flight" response during threatening situations is the role of the ________.
sympathetic nervous system
The blood-brain barrier is formed by ________ junctions that nearly seamlessly bind capillaries in the brain.
tight
(T/F) The primary motor area allows us to consciously move our skeletal muscles.
true
What cranial nerve pair supplies many organs in the ventral body cavity?
vagus nerves
Myelinated fibers (tracts) form ________ matter while unmyelinated fibers form ________ matter.
white; gray
Central Nervous System
-CNS -brain and spinal cord -integrating and command centers
Peripheral Nervous System
-PNS -communication lines with the body -cranial and spinal nerves
Anencephaly disorder
-cerebrum fails to develop -failure to hear, see, or process sensory inputs
Spina bifida disorder
-incomplete vertebrae formation -inability to control the bowels or bladder -paralyzed lower limbs
Cerebral palsy disorder
-neuromuscular disability, possibly from temporary oxygen loss -spastic, poorly controlled muscles -possible mental retardation and impaired hearing or vision
Synaptic response to an action potential
1. an action potential arrives at the synaptic terminal 2. calcium channels open, and calcium ions enter the synaptic terminal 3. vesicles containing neurotransmitter fuse with the plasma membrane of the sending neuron 4. neurotransmitter molecules diffuse across the synaptic cleft 5. The neurotransmitter molecules bind to receptors in the plasma membrane of the receiving neuron, causing ion channels there to open
Which one of the following is the correct sequence of events that correlates to the sequence of events of a nerve impulse? 1. the membrane becomes depolarized 2. sodium channels open and sodium ions diffuse inward 3. the membrane becomes repolarized 4. potassium channels open and potassium ions diffuse outward while sodium is actively transported out of the cell
2, 1, 4, 3
Which of the following can adversely affect brain development?
alcohol
What cells of the nervous system are responsible for anchoring neurons to their blood vessels and controlling the extracellular fluid concentrations of potassium and neurotransmitters?
astrocytes
What is the most abundant glial cell in the central nervous system (CNS)?
astrocytes
Which of the following conditions would result from damage to the cerebellum?
ataxia