Vascular and Ventricular Systems

CSF is mainly produced by what structure?

• The choroid plexus in the lateral ventricle

• The choroid plexus in the lateral and third ventricles

• The choroid plexus in the lateral, third and fourth ventricles

• The choroid plexus in the lateral, third, fourth and central canal

Answer explanation

What is the main function of the CSF?

• To keep the brain and spinal cord lubricated like oil in an engine

• To clean the brain and spinal cord like a car wash

• To protect the brain and spinal cord by acting as a shock absorber

• To transport signals from the brain to the spinal cord

What supporting cells are responsible for the creation and circulation of CSF?

• Satellite cells

• Ependymal cells

• Purkinje cells

• Epithelial cells

Answer explanation

Ependymal cells

*Found in the CNS

*Produces cerebrospinal fluid

*Cilia on their uppermost surface helps to circulate the cerebrospinal fluid

What does hydrocephalus mean?

• Water on the bridge

• Water on the skull

• Water on the floor

• Water on the brain

What large vessel is formed by the union of the two vertebral arteries?

• Basilar artery

• Common carotid artery

• Aorta

• Anterior cerebral artery

• Anterior communicating artery

Answer explanation

●Vertebral arteries give rise to small branches in the neck that supply the spinal cord and other neck structures

●Enters the foramen magnum and merge to form a single basilar artery along the medulla

●Branches of the basilar artery supply the:

○Cerebellum

○Pons

○Inner ear

●At the pons-midbrain junction, the basilar artery divides and gives rise to the Circle of Willis

What arteries account for most of the blood supply to the brain?

• The two posterior cerebral arteries

• The two anterior cerebral arteries

• The two internal carotid arteries

• The two external carotid arteries

• The two vertebral arteries

Answer explanation

Internal carotid artery

●Passes medial to the angle of the mandible

●Enters the cranial cavity through the carotid canal of the temporal bone

●Supplies the orbits and ~85% of the cerebral blood flow

●Each internal carotid artery gives rise to the following:

○Ophthalmic artery (orbits, nose, forehead)

○Anterior cerebral artery (medial aspect of the cerebral hemisphere)

○Middle cerebral artery (supplies the lateral aspect of the temporal and parietal lobes)

What structure makes collateral circulation to the brain possible due to a vascular anastomosis at the base of the brain?

• The Circle of Willis

• The Circle of Friends

• The Circle of Ranier

• The Circle of Williamsburg

Answer explanation

●The blood supply to the brain is so critical that it is furnished by several vascular anastomoses called the Circle of Willis at the base of the brain

●Surrounds the pituitary gland and optic chiasm

●Receives blood from the internal carotid and basilar arteries

●

●Main function of the Circle of Willis is to provide a collateral blood flow between the anterior and posterior arterial systems of the brain

○Also offers alternate blood flow pathways between the right and left cerebral hemispheres

The middle cerebral artery supplies what areas of the brain?

• The frontal lobes and medial aspects of the parietal and occipital lobes

• The insula, most of the lateral surface of the cerebral hemisphere, the anterior temporal tip

• The rostral midbrain, posterior thalamus, medial occipital lobe, and inferior and medial surfaces of the temporal lobe

Answer explanation

Anterior cerebral artery: supplies the frontal lobes and medial aspects of the parietal and occipital lobes

Middle cerebral artery: Supplies the insula, most of the lateral surface of the cerebral hemisphere, and the anterior tip of the temporal lobe

Posterior cerebral artery: supplies the rostral midbrain, posterior thalamus, medial occipital lobe, and inferior and medial surfaces of the temporal lobe

The posterior cerebral artery supplies what areas of the brain?

• The frontal lobes and medial aspects of the parietal and occipital lobes

• The insula, most of the lateral surface of the cerebral hemisphere, the anterior temporal tip

• The rostral midbrain, posterior thalamus, medial occipital lobe, and inferior and medial surfaces of the temporal lobe

Answer explanation

Anterior cerebral artery: supplies the frontal lobes and medial aspects of the parietal and occipital lobes

Middle cerebral artery: Supplies the insula, most of the lateral surface of the cerebral hemisphere, and the anterior tip of the temporal lobe

Posterior cerebral artery: supplies the rostral midbrain, posterior thalamus, medial occipital lobe, and inferior and medial surfaces of the temporal lobe

The anterior cerebral artery supplies what areas of the brain?

• The frontal lobes and medial aspects of the parietal and occipital lobes

• The insula, most of the lateral surface of the cerebral hemisphere, the anterior temporal tip

• The rostral midbrain, posterior thalamus, medial occipital lobe, and inferior and medial surfaces of the temporal lobe

Answer explanation

Anterior cerebral artery: supplies the frontal lobes and medial aspects of the parietal and occipital lobes

Middle cerebral artery: Supplies the insula, most of the lateral surface of the cerebral hemisphere, and the anterior tip of the temporal lobe

Posterior cerebral artery: supplies the rostral midbrain, posterior thalamus, medial occipital lobe, and inferior and medial surfaces of the temporal lobe