If the telencephalon was removed from a 5-week-old embroyo, which structures would fail to develope in the fetus?
The blood-CSF barrier is formed by?
The pyramind of the medulla oblongata contain?
Descending corticospinal fibers
Does not receive any input from the eyes?
The frontal lobe
While studying in a noisy cafeteria, you get sleepy and does off. You awaken with a start and realize that all the cafetria sounds have just "come back." While you were dozing, this auditory input was blocked from reaching your auditory cortex by
The reticular activating system.
Because of a brain lesion, a patient never feels full, but eats so excessively that she now weighs 600 lb.The lesion is most likely in her
The _______ is closely associated with the cerebellum in embryonic development and remains its primary source of input fibeers throughout life.
Damage to the ________ nerve could result in defects of eye movement.
All of the following except the _________ nerve begin or end in orbit. a. optic b. oculomotor c. trochlear d. abducens e. accessory
The right and left cerebral hemispheres are connected to each other by a thick C-shaped bundle of fibers called _________.
The brain has four chambers called _________ filled with _________ fluid.
Ventricles & Cerebrospinal
On a sagittal plane, the cerebellar white matter exhibits a branching pattern called the ___________.
Abnormal accumulation of cerebrospinal spinal fluid in the ventricles can cause a condition called ________.
Cerebrospinal fluid is secereted parttly by a mass of blood capillaries called the ________ in each ventricle.
The primary motor area of the cerebrum is the _______ gyrus of the frontal lobe.
A lesion in which lobe of the cerebrum is most likely to cause a radical alteration of the presonality?
Area of cerebral cortex that identify or interpret sensory information are called _____________ _______
Linear, analytical, and verbal thinking occurs in the ________ hemisphere of the cerebrum, which is on the left in most people.
The major pattern for speech is generated in he area of cortex called the _________ and then transmitted to the primary cortex o be carried out.
The two hemispheres of the cerebrals are seperated by __________ _________.
The cerebral hemispheres do not develope from ________ __________ tissue.
The midbrain is caudal to the ____________.
The Broca area is ipsilateral to the ___________ area.
The choroid plexus produces only ________ of the CSF.
Hearing is a __________ ________ function; vision resides in the _________ ________.
Temporal lobe; Occipital lobe
Respiration is controlled by nuclei in both the _______ and the _________ __________.
Pons; Medulla Oblongata
The __________ _________ carries sensory signals from the larger area of the face than the ________ _______ does.
Trigeminal; Facial nerve
Unlike cranial nerves, the _________ nerve extends far beyond the head-neck region.
The __________ contains more than half of brain neurons.
_________ _________ is not innervated by the autonomic nervous system.
Muscarinic receptors bind _______________.
_________________ does not carry parasympathetic fibers.
The ganglia ________ is not involved in the sympathetic division.
Epinephrine is secreted by ____ ____________ ____________.
The adrenal medulla
The most significant autonomic control cented within the CNS is ___ ____________.
The gray communicating ramus contains _____________ _________________ __________.
Sympathetic postganglionic fibers
Throughout the autonomic nervous system, the neurotransmitter released by the preganglionic neuron binds to ___________ receptors on the posganglionic neuron.
Does not result from sympathetic stimulation
Certain nerve fibers are called ___________ fibers because they secrete norepinephrine.
Is a state in which a target organ receives both sympathetic and parasympathetic fibers.
Is a state of continual background activity of the sympathetic and parasympathetic divisions.
Most parasympathetic preganglionic fibers are found in ________ nerve.
The digestive track has a semi-independent nervous system called the _________ nervous system.
MAO and COMT are enzymes that break down _____________ at certain ANS synapses.
The adrenal medulla consist of modified postganglionic neurons of the ______________ nervous system.
The sympathetic nervous system has short _____________ and long ______________ nerve fibers.
Adrenergic receptors classified as a1, B1, and B2 act by changing level of ______ in target cell.
Sympathetic fibers to blood vessels maintain a state of partial casconstriction called __________.
Both parasympatheric and sympathetic systems can be active _______________.
Blood vessels of the skin receive no _____________ ____________.
Limited ___________ ____________ of the ANS is possible
The sympathetic division inhibits ___________.
Urination and defecation cannot occur without signals from the brain to _____________ and ___________.
Bladder and rectum
Some sympathetic postganglionic fibers are ____________.
ALL ______________ fibers are cholinergic.
Parasympathetic effects are more __________ and __________ than sympathetic effects.
The parasympathetic division shows less _______ ___________ than the sympathetic division does.
The two divisions of the ANS have _____________ _________ on the iris.
Olfactory epithelium. Special sense of smell.
Retina of eye. Special sense of vision.
Inferior, medial, superior rectus, inferior oblique and levator palpebrae superioris, muscles, intrinsic eye muscles. Eye movement.
Superior oblique muscle. Eye movement.
Areas associated with the jaws. Mixed to face
Lateral rectus muscle. Eye movements
Sensory: taste receptors on anterior 2/3 of tongue; motor: muscles of facial expression, lacrimal gland, submandibular gland, sublingual salivary glands. Mixed to face
VII Vestibulocochlear (Acoustic)
Cochlea (receptors for hearing) and vestibule (receptors for motion and balance). Special sensory: balance and equilibrium (vestibular) and hearing (cochlear)
Sensory: posterior 1/3 of tongue, pharynx and palate, receptors for blood pressure, pH, oxygen and carbon dioxide concentration; motor: pharyngeal muscles and parotid salivary gland. Mixed to head and neck
Sensory: pharynx, auricle and external acoustic canal, diaphragm, visceral organs in thoracic and abdominopelvic cavities; motor: palatal and pharyngeal muscles and visceral organs in thoracic and abdominopelvic cavities. Mixed, widely distributed in the thorax and abdomen.
Internal: Skeletal muscles of palate, pharynx, and larynx (with vagus). External: Sternocleidomastoid and trapezius muscles. Motor to muscles of neck and and upper back.
Tongue musculature. Tongue movements.
Toward the forehead
Toward the spinal cord
Major parts of the brain
Cerebrum, Cerebellum and Brainstem
83% of brain volume
Is 10% of brain volume, but contains 50% of neurons
Nervous system developes from
Early the 3rd week of embroyo development, a dorsal streak called _______________________ which thickens to form a neural plate developes.
By 3'rd week of embroyonic development the neural plate becomes a __________ with folds on each side.
By the 4th week of embroyonic development, neural folds join to form the ___________ _______.
Lumen of the neural tube developes into central canal of spinal cord and _________ __ ___ ______.
Ventricles of the brain
Cells along the margin of the neural groove is called _______ ________.
Falx cerebri, falx cerebelli and tentorium cerebelli
4th week - The forebrain (prosencepehalon) subdivides into two vesicles called the
telencephalon and diencephalon
4th week- The midbrain (mesencephalon) remains undivided abd retains the same name
4 th week- The hindbrain (rhombencephalon) subdivides into two vesicles called
Metencephalon and myelincephalon
5th week (from forebrain subdivision) telencephalon forms _________ ________ and _______ _________.
Cerebral cortex and basal ganglia
5th week (from forebrain subdivision) diencephalons forms ___________ & ________________
thalamus and hypothalamus
5th week (from midbrain) mesencephalon forms
All parts midbrain. Mesencephalon does not subdivide it remains midbrain.
5th week (from hindbrain subdivison) metencephalon forms ______ and ________________
Pons and cerebellum
5th week (from hindbrain subdivision) myelencephalon forms _________ _________.
Outermost, tough membrane. Periosteal layer against bone.
From where dura mater seperates from inner meningeal layer it forms ________ ________ _______ which drains blood from brain.
Dural venus sinus
Two major dural sinuses are
Superior sagittal sinus & transverse sinus. (These meet like a T at the back of the brain and empty into jugular veins at the back of the neck.)
Falx Cerebri extended ______________________ that seperates right and left hemisphere.
Tentorium Cerebelli stretches like a roof over the posterior cranial fossa and seperates the _____________ from the overlying _______________.
Falx Cerebelli, partially seperates the right and left halves of the ______________ on the inferior side.
Epidural space filled with _____ in the lower back region.
Fat (Epidural anasthesia during childbirth)
A spider wed filamentous layer. Transparent membrane over brain surface.
Seperates arachnoid mater from pia mater below it
Subarachnoid spaces. CSF flows in subarachnoid space.
Brain has four internal chambers within the CNS which hold CSF called
Largest, most rostal ventricle that forms an arch in each cerebral hemisphere
Interventricular foramen is
Tiny pore which connects each laterial ventricle to the 3'rd ventricle
Each laterial ventricle is connected to the __________ __________, a narrow medial space inferior to the corpus collosum. _______ of CSF is produced here.
Third ventricle, 30% of CSF
From the 3rd ventricle, a canal called the ___________ __________ passes down the core of the midbrain and leads to the 4th ventricle.
The 4th ventricle is a small triagular chamber between the _______ and ______________
Pons and cerebellum
Caudally, the 4th venticle narrows and forms a _________ _________ which extends through the medulla oblongata into the spinal canal.
Ventricles are lined with _____________ _______ and contain choroid plexes of capillaries that produce CSF.
Epedemial cells. (Epedemial cells cover Choroid plexus and produce 30% of CSF)
On wall of each venricle is a spong mass of blood capillaries called
A type of neurogilia which resembles cubodial epithelium. Lines ventricals of canals and covers choroid plexus.
Clear colorless liquid that fills ventricles and canal of CNS. Bathes external surface of brain. (in subarachnoid space)
Cerebrospinal fluid (CSF)
Brain produces and absorbs 500 mL per day
Cerebrospinal fluid (CSF)
CSF production begins with with filtration of _________ __________ through capillaries which ___________ _______ modify as filtrate passes through them.
blood plasma, ependymal cells
CSF is not ______________ but _____________ ________ through and around CNS.
stationary, continually flows (by way of its own pressure, cilia on ependymal cells and rythemic pulsation that is produced by heartbeat.)
CSF has more Ka+ (sodium) & Cl+ (chloride) but less K+ (potassium) & Ca+2 (calcium) than blood plasma.
CSF provides ____________, _____________ and _____________ _____________.
Buoyancy, protection, ad chemical stability
CFS escapes out the ____ ___________ to surround the brain.
CFS is absorbed the _________ _________ into the venous sinus.
A pore in the wall of the 4th ventricle which CSF escapes out of and is led into the subarachnoid space.
Two pore of the 4th ventricle which CSF escapes out of and is led into the subarachnoid space.
Dural Sinus spaces that collect blood that has been circulated through the __________ and ultimately empty into the internal jugular veins of the neck.
Cauliflower shaped extentions if the arachnoid menix that protrudes through the dura mater into the superior sagittal sinus that absorbs CSF.
1) CSF is secreted by the ___________ ___________ in each ___________ ventricle.
Choroid Plexus, lateral
2) CSF flows through ________________ foramina into ______ ventricle.
3) Choroid plexus in the ________ ventricle adds _________ CSF
4) CSF flows down ____________ _______________ to ______ ventricle.
Cerebral aqueduct, 4th
5) __________ ___________ in the _____ ventricle adds _______ CSF.
Choroid plexus, 4th, more
6) CSF flows out of the ____ _________ aperatures and ____ ___________ aperature.
Two lateral, one medial
7) CSF fills the _____________ ___________ and bathes ___________ ____________ of brain and spinal cord.
subarachnoid space, external surfaces
8) At ______________ __________, CSF is reabsored into ____________ ___________ of dural __________ sinus.
Arachnoid villi, venous blood, venous
Blood Brain Barrier is tightly joined ______________ cells
Cells that line blood vessles, specifically capillary walls
The brain ______ of body weight, but receives ______ of blood supply, and consumes 20% of oxygen and glucose.
10 second interruption of blood flow can cause loss of consciousness. 1-2 minutes can significantly impare neural function. 4 minutes without blood causes _____________ ________ _________
irreversible brain damage
BBB (Blood Brain Barrier) strictly regulates what subsances get in from the _________ __________ into the _________ _________ of the brain.
Blood stream, tissue fluids
Blood Brain Barrier (BBB) is
tightly joined endothelium
BBB is permeable to __________ ___________ materials (alcohol, 02, CO2, nicotine, anesthetics, H20 and glucose).
The ___________ of the brain are well protected by BBB which consist of tight junctions of endothelial cells that form ___________ _______.
Capillaries, capillary walls
BBB ensures that anything leaving the ________ must pass through the cells and not between them.
Tight junction endothelium cells exclude ___________ ____________ from _________ tissue while _____________ ______________ ones to pass through.
harmful substances, blood, allowing necessary
At _________ __________ the brain is protected by a similar blood- CSF barrier formed by _________ ___________ between ___________ ________.
Choroid plexus, tight junctions, ependymal cells
Tight junctions are ___________ from ependymal cells outside of Choroid plexus.
Where trauma and inflammation sometimes damage the BBS (Brain Barrier System) there are places called ___________________ ___________ in the 3rd and 4th ventricles where barriers are absent and the blood has direct access to the brain.
Circumventricular Organs (CVOs)
_____________ ___________ are in the 3'rd and 4th ventricles at breaks in the barrier where blood has direct access.
Circumventrical Organs (CVOs)
Circumventricular Organs (CVOs) allow
The brain to monitor and respond to fluctuations in blood glucose, pH, osmolarity & other variations.
Unfortunately Circumventricular Organs (CVOs) can afford a potential route of invasion by the _____ ________.
HIV virus (human immunodeficency virus) to invade the brain.