Anatomy 2 Flashcards
What is the anterolateral system (also called the Lateral Spinothalamic Tract) of the spinal cord?
An ascending somatosensory pathway carrying information regarding pain and thermal sensations
What is the blood-brain barrier?
The tight junctions in the endothelial cells that line the capillaries of the central nervous system which prevent most macromolecules from entering or leaving the central nervous system
The outer 2-4 mm of the cortex is made up of gray matter that has been divided into how many horizontal layers?
6
What is contained in the dorsal root ganglia?
Cell bodies for the sensory axons of the spinal nerves
The fasciculus gracilis and fasciculus cuneatus are located in the…
Dorsal white columns
What is the name of the structure which made from the pia extending through the cauda equina from the conus medullaris to the end of the dural sac around the spinal cord, and anchoring the spinal cord in the area of the the coccyx?
Filum terminale
Are action potentials a local and graded response?
No
What are the ABCDE’s of melanomas?
A: Asymmetry
B: Borders that are uneven vs smooth
C: Color variety or change
D: Diameter that is relatively large
E: Evolving, changing in size, shape, elevation, color, etc.
Where are pseudo-unipolar cells found?
Dorsal root fibers with the dorsal root ganglia
Which artery supplies blood to the area of the superior temporal gyrus and lateral fissure, including the area of the primary auditory cortex?
Middle cerebral artery
How does CSF flow?
CSF is produced by choroid plexus and flows from the 2 lateral ventricles through the interventricular foramina to the third ventricle and then through the cerebral aqueduct to the fourth ventricle and then out into the subarachnoid space
What is the specific name of the condition caused when there is an occlusion of the foramina of the 4th ventricle resulting in a build-up of CSF within the ventricles that cannot escape into the subarachnoid space to circulate and be reabsorbed?
Noncommunicating hydrocephalus
What type of cells form myelin on the axons in the peripheral nervous system?
Schwann cells
How is the circle of willis formed?
The circle of willis is formed due to both of the posterior communicating arteries and the anterior communicating artery. The posterior communicating arteries connect the internal carotid to the posterior cerebral artery on both sides of the brainstem. The anterior communicating artery connects the two anterior cerebral arteries. The communicating arteries usually only have a little blood flow, or none at all, and their main function is to equalize pressure and shunt blood over to another artery if there is an occlusion
What is a dermatome?
An area of skin supplied by a single afferent spinal nerve (from a single dorsal root)
Where are the dorsal root ganglia located?
In the peripheral nervous system just outside of the dorsal side of the spinal cord and vertebrae
Which type of proprioceptors detect/measure muscle length?
Muscle spindles
What are golgi tendon organs?
What is the action of the sodium-potassium pump?
To actively pump 3 sodium (Na+) ions out of the cell and 2 potassium (K+) ions into the cell to maintain the correct balance for the resting membrane potential
What are the names of the major arteries that bring blood from the heart to the central nervous system (coming off of the aorta and subclavian arteries)?
Carotid arteries (internal carotid to CNS) and vertebral arteries
Where is Rexed’s lamina II (two) in the spinal cord located?
In the dorsal gray horns
Separations in the layers of the dura form cavities which are part of the drainage system of the brain and are known as…
Venous sinuses
True or False: One oligodendrocyte can extend to 20 or more axons to envelope them, forming the myelin sheath
True
During embryologic development, six hillocks of tissue form around both sides of the first branchial groove. What do these hillocks eventually become?
The pinna
During embryological development of the central nervous system, which secondary vesicle of the neural tube becomes the pons, cerebellum and a portion of the fourth ventricle?
Metencephalon
What is CN V?
Trigeminal
Sensory information from the face and motor innervation of mastication and to the tensor tympani
What is CN VI?
Abducens
Motor control of the lateral rectus eye muscles
What is CN VII?
Facial
Sensory info from tongue through the chorda tympani and motor control for facial expression and the stapedius muscle
What is CN XI?
Accessory
Motor control of sternocleidomastoid and trapezius
What is CN XII?
Hypoglossal
Motor for intrinsic and extrinsic muscles of the tongue
What is the glossopharyngeal nerve?
Motor for pharynx and palate and taste
What is the vagus nerve?
Parasympathetic motor function for heart, lungs, etc.
And sensory
What is the trochlear nerve?
Motor control of superior oblique eye muscles
CN VIII enters or exits the brainstem at…
The pontomedullary junction or cerebellopontine angle
Which extrinsic eye muscles are innervated by CN III?
Superior rectus
Inferior rectus
Inferior oblique
Medial rectus
What is meant by the term branchiomeric nerves?
Cranial nerves that innervate branchial arch musculature such as CN V, VII, IX, X and XI
Which branchial arches play a major role in development of ear structures?
Branchial arches 1 and 2
The cerebellum is connected to the main body of the pons by 3 pairs of fiber tracts known as the…
Cerebellar peduncles
Of the cerebral cortex layers, which layer is most superficial and which is the deepest?
Layer 1 is the most superficial and 6 is the deepest
The superior and inferior colliculi are located in which area of the brainstem?
Tectum of the midbrain
Which type of degeneration involves the distal portion of the axon that has been severed from the cell body and leaves Schwann tubes that may aid in regeneration?
Orthograde degeneration
What pathway projects primarily from the primary motor cortex, decussating in the pyramids of the medulla, traveling to the lateral white columns in the spinal cord to the ventral gray horn and then innervating muscles to provide the main control of voluntary skilled movements?
Corticospinal tract
What pathway projects from the medial and lateral vestibular nuclei to the spinal cord to act upon interneurons and motor neurons to control antigravity muscles for postural control?
Vestibulospinal tracts
What is the fasciculus gracilis?
Carries somatosensory information including touch and proprioception from the lower extremities to the medulla as part of the dorsal column-medial lemniscus pathway
Intensity of a stimulus is represented by frequency modulation (rate of firing) for…
Action potentials
Embryologically, the central nervous system (including the brain and spinal cord), sense organs such as the cochlear and vestibular hair cells, and the skin are derived from which of the germ layers?
Ectoderm
What is the generic term that describes defects of the spinal cord, during embryologic development when the caudal neuropore does not properly close?
Spina bifida
Which inner ear fluid is able to flow through a duct to reach the subarachnoid space and is thought to be a derivative of CSF?
Perilymph
What is gastrulation?
The formation of the three primary germ layers
During embryologic development, which germ layer gives rise to the skeletal structures, circulation structures, meninges, and cartilage (including the ossicles and temporal bone)?
Mesoderm
Embryologically, development of the inner ear begins with formation of…
The otic placodes which are thickenings of ectoderm
Embryologically, what structures are derived from the neural tube and its tissues?
Central nervous system structures including structures such as the cerebrum, brainstem, cerebellum, ventricles and spinal cord
Which classification of nerve fibers have the slowest conduction velocity and are unmyelinated?
Group IV
The binding of a neurotramsmitter to a receptor site and depolarization of the post-synaptic cell membrane due to changes in the membrane permeability is an example of what?
Activation of ligand-gated ion channels
The two vertebral arteries merge near the pontomedullary junction to form what artery?
The basilar artery
What is the reticular formation?
Diffusely organized groups of cell bodies throughout core of the brainstem which help with integration of many types of information
Which motor pathway carries information from the reticular formation of the pons and medulla to all levels of the spinal cord to influence muscle tone in the lower extremities?
Reticulospinal tract
Where is Rexed’s lamina I (one) in the spinal cord located?
In the initial portion of the dorsal gray horns (the most dorsal layer)
What is scarpa’s ganglia?
The cell bodies of the bipolar afferent vestibular CN VIII fibers located in the internal auditory canal
Some vestibular information being carried by CN VIII and coming from the vestibular nuclei is carried to the cerebellum. What is the route and location in the cerebellum where vestibular information is processed?
Nerve fibers carrying vestibular information reach the cerebellum via the juxtarestiform body of the inferior cerebellar peduncle and the information is processed primarily in the flocculonodular lobe
A reduction in blood flow can be caused by a local, attached clot in a blood vessel caused by an atherosclerotic plaque. What is this vascular abnormality called?
Thrombosis
Which artery supplies blood to the area of the superior temporal gyrus and lateral fissure, including the area of the primary auditory cortex?
Middle cerebral artery
During embryologic development, what does the tubotympanic recess eventually become?
The middle ear cavity and the ET
Which reflex refers to the response when an infant is startled and then throws out his/her arms and legs and begins to cry?
Moro
What is the location of the primary auditory cortex (A1)?
A1 is located on the transverse gyri of the superior temporal gyrus of the temporal lobe, inside the lateral fissure
In the embryo, which flexure of the developing neural tube marks the location where the future brainstem meets the future spinal cord, and this bend straightens out over time during development?
Cervical flexure
Once a nerve reaches its threshold to fire an action potential, what is the FIRST step is a change in membrane permeability along the axon to begin the propagation of the bioelectrical change that is the action potential?
The opening of voltage-gated ion channels allowing an influx (inward flow) of Na+ to rapidly depolarize the neuron at the axon hillock
What term best describes the brief time period after the peak of an action potential during which another action potential cannot be generated no matter how much the cell membrane is depolarized?
Absolute refractory period
What is the resting membrane potential of a neuron?
The inside of the cell is about -70 millivolts compared to the extracellular fluid due to a high concentration of sodium outside of the cell and a high concentration of potassium inside the cell
When action potentials reach the terminal bouton of a neuron, what occurs to allow for synaptic transmission of the signal to the next cell (the post-synaptic cell)?
Voltage change triggers opening of Ca++ channels at the bouton, inward flow of Ca++, and then the release of neurotransmitters into the synaptic cleft
A nonacoustic middle ear muscle reflex can be used to provide additional diagnostic information if the acoustic middle ear muscle reflex is absent. What are the muscles evaluated and the stimuli used to generate the nonacoustic middle ear muscle reflex?
Tactile stimulation of the facial skin or a puff of air into the eye or sudden lifting of the upper eyelid can cause the stapedius and/or tensor tympani muscles to contract
If there is a patient with Bell’s Palsy, which test below might an audiologist use to help in diagnosis and assessment of recovery from the palsy?
ART
True or False: There is no somatotopic mapping of body parts/areas in the pathways of the spinal cord because somatotopic mapping only begins in the primary motor and primary somotosensory cortices in the cerebrum
False
What is located directly beneath the arachnoid mater?
Subarachnoid space filled with cerebrospinal fluid
Following a skull fracture and the tearing of meningeal arteries, there may be bleeding between skull bones and the dura that can be fatal unless treated. This is known as a/an…
Epidural hematoma
What is the specific name of the condition caused when there is a build-up of CSF within the subarachnoid space due to a lack of absorption after the CSF has exited the ventricles and is flowing in the subarachnoid space?
Communicating hydrocephalus
What type of cells form myelin on the axons in the central nervous system?
Oligodendrocytes
The ability to sense the position of one’s limbs is known as…
Proprioception
Which glands of the skin release sodium chloride, urea, uric acid and other substances out through the skin and also help with heat regulation to cool the body?
Sweat glands
What is the largest bundle of axons that serves as the main interhemispheric connection between the right and left hemispheres?
Corpus callosum
Which type of proprioceptors detect/measure muscle tension?
Golgi tendon organs
Separations in the layers of the dura form cavities which are part of the drainage system of the brain and are known as…
Venous sinuses
Which layer of the skin mainly contains adipose (fat) tissue?
Hypodermis/subcutaneous
What are some terms used to refer to a collection/bundle of axons in the CNS?
Fasciculus
Lemniscus
Peduncle
Funiculus
What are some structures that are related to the limbic system?
Cingulate gyrus
Amygdala
Hippocampus
What is agnosia?
The inability to recognize an object or interpret sensory stimuli
What is the designator used to represent the left ear?
A1
True or False: Febrile seizures are a definite early warning sign of the presence of epilepsy
False
What happens during the light reflex of the visual system when a bright light is directed into one eye?
The stimulation goes to the brainstem via CN II and then causes CN III to activate the pupillary constrictors in both eyes
What is the premotor area?
Aids in preparation for motor movements
What is the supplemental motor area?
Facilitates coordination of complex movements and is not needed for simple repetitive tasks
A lesion to the cortex resulting in weakness of the extraocular eye muscles interrupting voluntary saccades but with intact ocular reflexes is an example of which of the following?
Supranuclear ophthalmoplegia
Which answer below best describes activities mediated by the parasympathetic nervous system?
Decreasing heart rate, increasing digestive activity and pupillary constriction
Which photoreceptors of the retina are responsible for color vision?
Cones
Why do most individuals exhibit a right ear advantage when listening to complex speech stimuli?
Because the right ear is most directly connected to the left brain which is the speech dominant hemisphere for most people
TRUE or FALSE: All patients who have tinnitus in one or both ears are extremely debilitated by it and cannot work or enjoy daily activities due to the strong emotional and physiological responses they have to the sounds
False
T/F: The right visual field is represented in the visual cortex on the left side of the brain
True
What is ballismus?
A movement disorder characterized by a “jumping about” movement where an arm or leg shows wild flailing movements
What is the name for the type of pain described by someone feeling pain in the chest wall or left arm when the stimulation is from the heart due to myocardial ischemia (a heart attack)?
Referred pain
What area in the eye creates the natural blind spot?
The optic disk
Review projected pain
Which fluid in the eyeball is the jelly-like semifluid which is important for maintaining the round shape of the globe of the eyeball?
Vitreous fluid
If a patient has spontaneous nystagmus, why might you not see it when the patient comes to your office and you are taking their case history?
Because the ability to visually fixate on objects in a lighted room masks or controls the nystagmus
How would you describe a type of lesion that would result in a contralateral lower quadratic anopsia?
A lesion impacting a portion (one half) of the optic radiations, specifically those going to the cuneus gyrus on one side
How does blood flow?
Deoxygenated blood from the body returns to the heart through the superior and inferior vena cava
How many pulmonary veins exist in the cardiovascular system?
4
What is the pathway of the autonomic nervous system (ANS) from the spinal cord to the periphery?
The ANS involves a 2-neuron path with preganglionic axons coming from cell bodies in the lateral gray horns of the spinal cord to synapse on peripheral ganglia with postganglionic axons then projecting to muscles or organs
What ASIA scale rating indicates the most severe injury?
ASIA A
During a neurological examination, observation of the patient’s ability to smile, grimace and raise their eyebrows to test for mimetic/facial expression muscle weakness is done to test which cranial nerve?
CN VII
Damage to one of the CN VI nuclei, resulting in a loss of lateral gaze and a medial diversion of the eye on forward gaze ipsilateral to the lesion, is an example of ….
Nuclear ophthalmoplegia
What is orthostatic hypertension?
A drop in blood pressure (20 mm Hg in systolic or 10 mm Hg in diastolic pressure) when moving from a supine position to an upright position (such getting out of bed and standing up) that can result in dizziness, fatigue, and blurred vision
What does paraplegia mean?
Paralysis of lower extremities
What is happening when the sympathetic nervous system is activated?
Increasing heart rate and blood flow to muscles, dilating the pupils, stimulating sweat and decreasing digestive activity
What is the fovea?
The region of highest visual acuity in the retina densely packed with cones, but not rods
What is the cornea?
Clear portion that is the outer protective layer in front of the lens
What is the choroid layer?
The middle layer of the eyeball that contains blood vessels and nerves
Tapping the patellar tendon causing a light stretch in the quadriceps followed by a reflexive contraction of the quadriceps and a knee jerk is an example of what type of reflex?
Stretch reflex
If someone steps on a nail with a bare foot and immediately pulls the foot up and off of the nail, this is an example of what type of reflex?
Flexor withdrawal or cutaneous reflex
What does the parasympathetic nervous system prepare our body for?
Rest and digestion
What is the purpose of the bicuspid, tricuspid and semilunar valves of the heart?
To prevent the backflow of blood to an area where the blood was just pumped from (such as not letting the blood flow backwards from a ventricle back up into an atrium)
What arteries supplies blood to the area of the occipital lobe?
Posterior cerebral arteries
Which artery provides the main blood supply to the face, including areas around the auricle/pinna and temporal and maxillary regions?
External carotid
In relation to the cardiac cycle, the systole phase refers to which of the following?
The contraction phase of the ventricles
What are erythrocytes?
Biconcave red blood cells that carry hemoglobin
What are leukocytes?
Granular and agranular white blood cells that function as part of the immune system response
What are thrombocytes?
Disk-shaped fragments that prevent blood loss from damaged vessels by aiding in formation of blood clots
What is albumin?
A plasma protein that aids in pressure/water balance and transportation of products that bind to it in the plasma
What is the most common blood type?
O+
What is myopia?
Elongated eyeball
Near-sighted
What is an astigmatism?
The cornea has inconsistent curvature that impacts the ability to focus
What is glaucoma?
Increases intraocular pressure from excess aqueous humor and tested by a puff of air in the eye
How do our eyes adjust to focus for near vision when an object like a book with small print is brought closer to our eyes?
Through convergence (eyes moving medially towards the nose), accommodation (rounding of the lens) and constriction of the pupils
Studies have shown that what functions are generally lateralized to the right hemisphere for most individuals?
Creative and artistic processing/skills
What is left hemineglect?
Lack of appreciation of spatial aspects and body parts on the left side
What are febrile seizures?
Abnormal neuronal firing in the cortex, usually benign and seen in infants
What is chorea?
Movement disorder showing continuous involuntary movements that appear almost like dancing
What is the main function of the kidneys?
To serve as the main organ for excretion, through the process of filtering blood and body fluids to extract waste and make urine
Which structure is a small-pear shaped sac that stores and concentrates bile until it needs to enter the duodenum of the small intestines?
Gallbladder
What is the main site of absorption of nutrients along the gastrointestinal tract?
Small intestines
Where is regeneration of neurons most likely to successfully occur?
Peripheral nervous system
What do nociceptors detect?
Tissue damage
About how long are the human intestines in a cadaver?
25-30 feet
Which structure/tube is the final passageway for food to reach the stomach?
Esophagus
Which organ shares a physiologic ultrastructure very similar to the stria vascularis in the cochlea so that toxins or genetic disorders my damage the ear and this organ?
Kidneys
Where is gas exchanged between the blood and the lungs?
In the alveoli
What is an antigen?
A toxin or foreign substance that induces an immune system response
What is the lymphatic system?
A network of vessels that drain fluid from tissues and towards the heart
Which side of the body drains 3/4 of the lymphatic fluids to a subclavian vein?
Left
What is hepatitis?
Infection/inflammation of the liver
What is peristalsis?
Involuntary constriction of muscles in the GI tract to move food/material forward along the tract
What is the function of the pleura and pleural fluid around the lungs?
To provide moisture and reduce friction
What is considered the functional filtering unit of the kidneys?
Nephrons
Which types of cell create myelin in the peripheral nervous system?
Schwann cells
What happens during inhalation?
The diaphragm contracts and pulls downward causing the thoracic cavity to expand
