13.3 Flashcards
What is the primary function of the blood-brain barrier?
A) To protect the brain from toxins and pathogens in the bloodstream
B) To allow all blood contents to pass into the central nervous tissue
C) To regulate body temperature
D) To control hormone levels
A) To protect the brain from toxins and pathogens in the bloodstream
Explanation: The blood-brain barrier ensures that only specific substances can pass into the brain, protecting it from harmful toxins and pathogens.
The CNS needs specialized structures for the maintenance of circulation, beginning with a unique arrangement of blood vessels carrying fresh blood into the _____.
A) Heart
B) CNS
C) Lungs
D) Liver
B) CNS
Explanation: Specialized structures and a unique arrangement of blood vessels are essential for maintaining circulation within the CNS.
The orthostatic reflex helps maintain blood pressure when changing body position.
A) True
B) False
A) True
Explanation: The orthostatic reflex responds to changes in body position to help maintain blood pressure, preventing dizziness or fainting upon standing.
Which artery supplies blood to the anterior aspect of the spinal cord?
A) Internal carotid artery
B) Anterior spinal artery
C) Vertebral artery
D) Basilar artery
B) Anterior spinal artery
Explanation: The anterior spinal artery supplies blood to the anterior aspect of the spinal cord, crucial for its function.
The circle of Willis is a specialized arrangement of arteries that ensure constant perfusion of the _____ even in the event of a blockage of one of the arteries in the circle.
A) Liver
B) Brain
C) Heart
D) Lungs
B) Brain
Explanation: The circle of Willis helps maintain a constant blood supply to the brain, even if one part is blocked.
After passing through the CNS, blood returns to the circulation through a series of dural sinuses and veins, including the _____ sinus and the transverse sinuses.
A) Superior sagittal
B) Inferior mesenteric
C) Coronary
D) Hepatic portal
A) Superior sagittal
Explanation: The superior sagittal sinus and the transverse sinuses play key roles in returning blood from the CNS to the heart.
The dura mater is a thin, delicate membrane that forms a loose sac around the CNS.
A) True
B) False
B) False
Explanation: The dura mater is a thick fibrous layer that forms a strong protective sheath over the brain and spinal cord.
What structure directly follows the convolutions of gyri and sulci in the cerebral cortex?
A) Dura mater
B) Arachnoid mater
C) Pia mater
D) Superior sagittal sinus
C) Pia mater
Explanation: The pia mater is a thin fibrous membrane that closely follows the contours of the brain’s gyri and sulci, providing an additional layer of protection and support.
Which meningeal layer is described as a tough outer covering that encloses the entire CNS?
A) Arachnoid mater
B) Dura mater
C) Pia mater
D) Subarachnoid space
B) Dura mater
Explanation: The dura mater is a thick, tough outer layer that physically protects the CNS and encloses major blood vessels.
The arachnoid mater is named for its resemblance to a spider web.
A) True
B) False
A) True
Explanation: The arachnoid mater is named for its web-like appearance due to the arachnoid trabeculae that span the subarachnoid space.
The subarachnoid space is filled with _____.
A) Blood
B) Cerebrospinal fluid (CSF)
C) Interstitial fluid
D) Air
B) Cerebrospinal fluid (CSF)
Explanation: The subarachnoid space is filled with CSF, which provides a cushion for the brain and spinal cord.
What is the purpose of a lumbar puncture?
A) To inject medication into the spinal cord
B) To withdraw cerebrospinal fluid (CSF) for testing
C) To relieve pressure in the brain
D) To measure blood pressure in the CNS
B) To withdraw cerebrospinal fluid (CSF) for testing
Explanation: A lumbar puncture is used to collect CSF for chemical testing to diagnose conditions like meningitis.
Bacterial meningitis can be treated with antibiotics, but viral meningitis cannot.
A) True
B) False
A) True
Explanation: Antibiotics are effective against bacterial infections, but viral infections do not respond to antibiotics.
What are the open spaces within the brain where cerebrospinal fluid (CSF) circulates called?
A) Sinuses
B) Ventricles
C) Arteries
D) Veins
B) Ventricles
Explanation: The ventricles are the open spaces within the brain where CSF circulates, providing cushioning and nutrient transport.
The CSF circulates through all of the ventricles to eventually emerge into the _____ where it will be reabsorbed into the blood.
A) Dural sinuses
B) Subarachnoid space
C) Interstitial space
D) Capillaries
B) Subarachnoid space
Explanation: CSF is eventually reabsorbed into the blood after circulating through the subarachnoid space.
Which ventricle connects to the third ventricle via the interventricular foramina?
A) Lateral ventricles
B) Fourth ventricle
C) Cerebral aqueduct
D) Central canal
A) Lateral ventricles
Explanation: The lateral ventricles connect to the third ventricle through openings called the interventricular foramina.
The pia mater is a thick fibrous layer that lines the inside of the skull.
A) True
B) False
B) False
Explanation: The pia mater is a thin fibrous membrane that closely follows the contours of the brain and spinal cord.
What produces cerebrospinal fluid (CSF) in the ventricles?
A) Choroid plexus
B) Ependymal cells
C) Arachnoid granulations
D) Superior sagittal sinus
A) Choroid plexus
Explanation: The choroid plexus, found in all four ventricles, is responsible for producing CSF by filtering blood.
The telencephalon takes on a C-shaped formation through the _____, _____, _____, and finally _____ regions.
A) Occipital, parietal, frontal, temporal
B) Parietal, frontal, occipital, temporal
C) Frontal, parietal, occipital, temporal
D) Temporal, occipital, frontal, parietal
C) Frontal, parietal, occipital, temporal
Explanation: The space within the telencephalon stretches into a C-shape through these regions of the brain.
The cerebral aqueduct connects the third ventricle to the fourth ventricle.
A) True
B) False
A) True
Explanation: The cerebral aqueduct passes through the midbrain and connects the third and fourth ventricles.
Which ventricle is bounded by the medial walls of the hypothalamus and thalamus?
A) First ventricle
B) Second ventricle
C) Third ventricle
D) Fourth ventricle
C) Third ventricle
Explanation: The third ventricle is surrounded by the medial walls of the hypothalamus and thalamus.
The CSF is reabsorbed into the blood at the _____.
A) Choroid plexus
B) Subarachnoid space
C) Arachnoid granulations
D) Central canal
C) Arachnoid granulations
Explanation: Arachnoid granulations allow CSF to filter back into the blood for drainage.
A stroke occurs when there is a blockage to an artery in the brain, leading to the deprivation of blood flow to surrounding tissues.
A) True
B) False
A) True
Explanation: A stroke results from a blockage that deprives the brain tissue of necessary blood flow and oxygen.
Which mnemonic helps remember the signs of a stroke?
A) RICE
B) CPR
C) FAST
D) ABC
C) FAST
Explanation: FAST stands for Face, Arms, Speech, and Time, key indicators to look for when someone may be experiencing a stroke.
What type of stroke is described as a “mini-stroke” and involves temporary blockage?
A) Hemorrhagic stroke
B) Ischemic stroke
C) Transient ischemic attack (TIA)
D) Lacunar stroke
C) Transient ischemic attack (TIA)
Explanation: A TIA is a temporary blockage of blood flow to the brain that can cause brief neurological symptoms.
Recovery from a stroke is highly dependent on the speed of treatment.
A) True
B) False
A) True
Explanation: Quick medical intervention is crucial for minimizing the long-term effects of a stroke and improving recovery outcomes.
The meninges from most superficial to deep are: dura mater, arachnoid mater, and pia mater.
A) True
B) False
A) True
Explanation: The meninges are three layers of protective tissue that cover the brain and spinal cord. From most superficial to deep, they are the dura mater, arachnoid mater, and pia mater. The dura mater is the outermost tough layer, the arachnoid mater is the middle web-like layer, and the pia mater is the innermost delicate layer adhering closely to the brain and spinal cord.
There are 31 pairs of spinal nerves extending from the spinal cord.
A) True
B) False
A) True
Explanation: There are 31 pairs of spinal nerves that extend from the spinal cord, each serving different regions of the body. These nerves are part of the peripheral nervous system and are crucial for transmitting sensory and motor information between the spinal cord and the rest of the body.
White matter of the spinal tract is composed of myelinated and non-myelinated fiber tracts.
A) True
B) False
A) True
Explanation: White matter in the spinal cord consists primarily of myelinated nerve fibers, which facilitate the rapid transmission of electrical signals along the nerves. However, it also contains some non-myelinated fibers, which are involved in slower signal transmission. The myelination gives the white matter its characteristic color.
Which of the following statements about the meninges is not true:
A) The dura mater is the most superficial of the meninges.
B) All are true statements
C) The dura mater extends inwards in areas to form dural septa which help prevent excessive movement of the brain.
D) In the spinal cord, the dura mater is not connected to the vertebral column; instead, the epidural space is located there.
E) In addition to protecting CNS structures, the meninges protect blood vessels and enclose the venous sinuses.
B) All are true statements
Explanation: All the provided statements about the meninges are accurate:
-The dura mater is the most superficial layer.
-The dura mater forms dural septa that help stabilize the brain.
-In the spinal cord, the dura mater is separated from the vertebral column by the epidural space.
-The meninges protect CNS structures, blood vessels, and enclose venous sinuses.
What are the four structures/features that protect the brain?
A) Dura mater, Arachnoid mater, Pia mater and microglia
B) Ventricles, blood brain barrier, meninges and CSF
C) Bone, Meninges, CSF, and neurons
D) Bone, Meninges, CSF, and the blood brain barrier
D) Bone, Meninges, CSF, and the blood brain barrier
Explanation: The brain is protected by several key structures:
Bone: The skull encases the brain, providing a hard, physical barrier against external impacts.
Meninges: These are three layers of protective tissue (dura mater, arachnoid mater, and pia mater) that surround the brain and spinal cord.
Cerebrospinal fluid (CSF): This fluid cushions the brain, providing a protective buffer against shocks and helping to maintain a stable environment.
Blood-brain barrier: This barrier regulates the passage of substances from the blood into the brain, protecting the brain from harmful chemicals and pathogens.
Match the gray matter horn or structure of the spinal cord with its best description:
A) Dorsal horns
B) gray commissure
C) Lateral horns
D) Ventral horns
- Contains cell bodies of somatic motor neurons
- Contains cell bodies of interneurons that receive somatic and visceral sensory input
- Contains cell bodies of sympathetic motor neurons
- Connects the two halves of gray matter in the spinal cord
A) Dorsal horns - 2. Contains cell bodies of interneurons that receive somatic and visceral sensory input
B) Gray commissure - 4. Connects the two halves of gray matter in the spinal cord
C) Lateral horns - 3. Contains cell bodies of sympathetic motor neurons
D) Ventral horns - 1. Contains cell bodies of somatic motor neurons
Explanation:
Dorsal horns receive sensory information and contain interneurons.
Gray commissure connects the left and right sides of the spinal cord.
Lateral horns are present in the thoracic and upper lumbar regions and contain sympathetic neurons.
Ventral horns contain motor neurons that innervate skeletal muscles.
Which of the following structures contains motor axons (both somatic motor and autonomic)?
A) Dorsal root ganglia
B) Ventral roots of the spinal cord
C) Dorsal roots of the spinal cord
D) Ventral horns
B) Ventral roots of the spinal cord
Explanation: The ventral roots of the spinal cord contain motor axons that transmit signals from the central nervous system to muscles and glands. These include both somatic motor axons, which control voluntary muscle movements, and autonomic motor axons, which control involuntary functions. The dorsal roots contain sensory axons, and the dorsal root ganglia contain the cell bodies of sensory neurons. The ventral horns contain the cell bodies of motor neurons but not the axons themselves.
Identify the structure labelled ‘E’ in the image of the spinal cord below (note: ventral view):
A) ventral horn
B) dorsal horn
C) dorsal roots
D) dorsal root ganglion
A) ventral horn
In the diagram below, what is the unlabeled region of the spinal cord?
A) Enteric
B) Brachial
C) Thoracic
D) Phrenic
C) Thoracic
