Download Mizzou Anatomy 2201 Hill Exam 3 With Complete Solutions Latest Update and more Exams Advanced Education in PDF only on Docsity!
Mizzou Anatomy 2201 Hill Exam 3 With Complete
Solutions Latest Update
SP: Common Fibular Nerve - ANSWER Sensory innervation- skin of antero-lateral leg, skin on dorsum of foot Motor innervation- Muscles of anterior leg, muscles of lateral leg Lesion to this nerve causes foot drop
Functions of the Nervous System - ANSWER 1. Collect information: (sensory input from PNS)
- Process and evaluate information: processes sensory input and determines response
- Respond to information: dictates response by activating effector organs
Nervous System: Somatic Sensory - ANSWER nerve endings in almost all body tissue has receptors for touch, pain, pressure, vibration, temp also for sense of body in space "special senses"
Nervous System: Visceral Sensory - ANSWER Sensations from the organs Only stretch and temperature
Nervous System: Somatic Motor - ANSWER Voluntary muscle system Contraction of skeletal muscles
Nervous System: Autonomic Motor - ANSWER Involuntary nervous system Regulates contraction of smooth and cardiac muscle and gland secretion
Can't control this Subdivides into sympathetic and parasympathetic
Nervous Tissue - ANSWER 2 types of cells: neurons and glia Neurons transmit electrical signals (excitable) Glia ("nerve glue") are supporting cells (not excitable)
Structure of a Neuron - ANSWER Dendrites- receive signal, transmit to cell body Soma (cell body)- contains nucleus cytoplasm, organelles Axon- (long cell process) transmits signal to exon terminals Myelin insulates axon
Neuron Signal Pathway - ANSWER Dendrite --> Cell body --> Axon --> Axon terminal More dendrites more impulses recieved
Synapse - ANSWER where an axon connects with another cell
Chemical Synapse - ANSWER Most numerous Uses neurotransmitters
Electrical Synapse - ANSWER rely on flow of ions at gap junctions
CNS Glia: Ependymal Cells - ANSWER Help produce CSF
CNS Glia: Microglia - ANSWER Defense
CNS Glia: Oligodendrocytes - ANSWER Myelinates axons
- Brain stem Midbrain Pons Medulla oblongata
Gray Matter - ANSWER is on the outer part of the brain Also the innermost regions Gray matter is unmyelinated neurons and neuron cell bodies
White Matter - ANSWER is made of myelinated axons, lies deep to the cortex of the brain
Diencephalon ("in between brain") - ANSWER Surrounded by cerebral hemispheres Contains 3rd ventricle
Thalamus - ANSWER Filters somatosensory, visual, and auditory info (all but smell) Any part of the brain that communicates with the cerebral cortex must go through this first "gate way to cerebral cortex"
Hypothalamus - ANSWER Main visceral control center of the body, regulates many activities
Epithalamus - ANSWER Includes pineal gland (which secretes melatonin for circadian rhythm)
Cerebrum - ANSWER Divided into two halves Left and Right hemispheres Each hemisphere is divided into 5 lobes: Frontal, Parietal, Occipital, Temporal, and Insula (deep to temporal and parietal lobes)
Cerebrum: Gyri and Sulci - ANSWER Gyri- ridges of the brain tissue, allow for more cortex to fit in the crainal vault Sulci- grooves between the gyri
Cerebral Functions - ANSWER Intelligence and complex thinking 3 types of functional areas
- Sensory - conscious awareness of sensation (senses)
- Association areas- integrate info (compare with previous experiences)
- Motor areas- voluntary motor functions (response of association areas)
Cerebrum: Primary Somatosensory Cortex - ANSWER In post central gyrus cortex that receives info from somatic senses and enables conscious awareness of the senses
Cerebrum: Primary Visual Cortex - ANSWER posterior/medial occipital lobe receives info from eyes (farthest possible from eyes)
Cerebrum: Primary Auditory Cortex - ANSWER in the temporal lobe, receives and process auditory info from inner ear
Cerebrum: Primary Motor Cortex - ANSWER Is located in precentral gyrus, Control voluntary skeletal muscle, also Broca's Area
Cerebrum: Broca's and Wernicke's Area - ANSWER Broca's- motor speech area, controls motor movements for speech. If damaged an understand speech but can't speak it very well (temporal lobe) Wernicke's- multimodal association area, recognition and understanding of speech. If damaged can speak but not comprehend language
Cerebrum: White Matter - ANSWER Corpus Callosum- is largest, most visible band of commissural tissue fibers (connect hemispheres
Folia: leaflike folds increase surface area Outer is gray matter What matter is Arbor Vitae (tree of life) (hindbrain)
Cerebellum: Processing - ANSWER Receives info from cerebrum on movements planned Compares planned movements with current body position Sends instructions back to cerebral cortex to readjust motor commands
Limbic System - ANSWER Involved with emotion and motivation, creating, storing, retrieving memories
- Cingulate gyrus-emotional response
- Hippocampus- stores memory
- Amygdala- processes fear Connected by fornix
Pia Mater - ANSWER Innermost lay, follows curves of brain, very delicate and lots of blood vessels
Arachnoid Mater - ANSWER Superficial to pia mater. Looks like spiderweb Subarachnoid space- weblike threads attach arachnoid mater to pia mater filled wit CSF
Dura Mater - ANSWER outmost layer Two layers
- Meningeal (Deepest)
- Periosteal (Superficial) These layers run together but split apart to form dural sinuses Also migraines occur in the pia mater
Dural Sinuses - ANSWER Drain blood from brain into the internal jugular vein. Anterior/Superior -> Posterior/Inferior: Superior Sagital Sinus> Straight Sinus> (Confluence>) Transverse Sinus> Sigmoid Sinus
Ventricles - ANSWER Lateral ventricles (1 and 2) communicate with 3rd via interventricular foramen 3rd ventricle drains into 4th via cerebral aqueduct circulate CSF
CSF - ANSWER Prevents damage/crushing Resists compressive forces, cushions against trauma, feeds brain, removes waste, carries chemical signals
CSF Flow - ANSWER 1. Made in choroid plexuses
- Flows thru ventricles > subarachnoid space
- Flows thru subarachnoid space
- Absorbed > dural venous sinuses ~500mL/day is processed/circulated
Brain Blood Supply - ANSWER Internal carotid divides into anterior and middle cerebral arteries. Anterior cerebral joins anterior communicating artery. Middle cerebral artery supplies ~80 of cerebrum (parts of temporal and parietal lobes)
Basilar Artery - ANSWER Formed by fusion of right and left vertebral, divides into posterior cerebral arteries (a/p cerebral connected by post. comm.) NOT part of Cerebral Arterial Circle
Circle of Willis (Cerebral Arterial Circle) - ANSWER Allows re-routing of blood flow through anastomosis
Epidural space that is filled with fat and veins (outside dura mater) Denticulate ligaments anchor spinal cord to dura mater
Spinal Cord: Clinical - ANSWER Epidural nerve block is injected between L4 & L5 w/o risk of damage to spinal cord. Cauda equina gets "pushed" out of the way if necessary.
Location of Spinal Nerves (in respect to vertebrae) - ANSWER Most cervical spinal nerves emerge SUPERIOR to their respective vertebrae (C1 nerve emerges superior to C1 vertebra) C8 nerve emerges inferior to C7 vertebra. Thoracic -> Coccygeal emerge INFERIOR to respective vertebrae.
Spinal Cord Gray Matter - ANSWER "H" shape, surrounded by white matter Commissure: unmyelinated axons crossing from one side to the other. Posterior arms = dorsal horns Anterior arms = ventral horns
Ventral and Dorsal Roots - ANSWER Dorsal horns receive information from sensory neurons (located in ganglia) Sensory neuron signals reach SC via DR. Ventral horns send out info to skeletal muscle. Signals to motor neurons travel via VR.
Spinal Nerves - ANSWER Formed by merged dorsal and ventral roots. Has both sensory and motor axons. Immediately splits into dorsal and ventral rami. Exits vertebral column @ intervertebral foramina.
Ventral Rami - ANSWER Carries both sensory and motor fibers.
Innervate most of the body, including trunk and limbs.
Dorsal Rami - ANSWER Carries both sensory and motor fibers. Innervate small portion of the back.
Reflexes - ANSWER Basic structural plan of NS, simple neuron chain. Usually exclude brain: rapid, automatic, unlearned motor response to stimuli. Signal synapses at SC. Ex. somatic: hot stove, visceral: vomiting.
Dermatome - ANSWER Area of skin supplied by a single spinal nerve. ALL spinal nerves except C1 have this. Numbness can pinpoint spinal cord injuries
Referred Pain - ANSWER When pain from an organ is mistakenly referred to dermatome. I.E. Appendicitis starts as pain in T10 dermatome.
Nerve Plexus - ANSWER A network of nerves formed only VENTRAL rami of spinal nerves only. All but T2-T12 branch and rejoin. Damage to one spinal nerve cannot completely paralyze and limb muscle.
Cervical Plexus - ANSWER Ventral rami of first 4 cervical nerves Most are sensory Some motor to anterior neck Phrenic nerve comes from C3, C4,C5- diaphragm
Brachial Plexus - ANSWER Partly in neck, partly in axilla
BP: Radial Nerve - ANSWER Sensory innervation: skin over dorso-lateral arm, forearm, and hand Motor innervation: posterior compartment of arm and forearm (all posterior compartment muscles)
Lumbar Plexus - ANSWER L1-L
LP: Femoral Nerve - ANSWER Sensory innervation: skin of antero-medial thigh, skin of medial leg and foot Motor innervation: muscles of anterior thigh (thigh flexors, leg extensors) TIP: F=front/flex
Sacral Plexus - ANSWER L4-S
LP: Obturator Nerve - ANSWER Sensory innervation: skin of medial thigh Motor innervation: muscles of medial thigh (adductors)
SP: Sciatic Nerve - ANSWER Tibial Nerve & Common Fibular Nerve togethe in common sheath Longest and thickest nerve of the body. serves all of lower limb except anterior/medial thigh
SP: Tibial Nerve - ANSWER Sensory innervation: skin of postero-lateral leg, skin of sole of foot (subdivides into plantar nerves) Motor innervation: Muscles of posterior thigh, muscles of posterior leg
Nerve Lesions: Clinical - ANSWER Phrenic: difficulty breathing Axillary: difficulty abducting arm to 90 degrees
Musculocutaneous: weakness flexing elbow Median: carpal tunnel syndrome, weakness flexing wrist Radial: difficulty extending elbow, wrist drop Ulnar: can't ad/abduct fingers, "funny bone" Femoral: walking probs, buckling knees Tibial: shuffling gait, difficulty w/ plantar flexing Common Fibular: foot drop
Autonomic Nervous System - ANSWER General PNS visceral motor system Involuntary control of visceral functions, regulates smooth and cardiac muscle and glands. Controls all the "routine" physiological functions.
ANS: Sympathetic - ANSWER ACTIVATES "fight or flight" Causes widespread, long lasting mobilization of fight or flight response Thoracolumbar: preganglionic neuron cell bodies in thoracic/lumbar SC. Emergencies, exercise, excitement
ANS: Parasympathetic - ANSWER INHIBITS "Rest and digest" These effects are highly localized and short lived Craniosacral: preganglionic neurons in brain/sacral regions of SC. Normal, everyday functioning.
Skin - ANSWER Largest organ in the human body 7% of total body weight
Dermis - ANSWER Underlies epidermis Strong, flexible connective tissue Highly vascularized Innervated (sensation) 2 cell layers: papillary-superficial (20%), reticular-deep (80%).
Hypodermis (subcutaneous) - ANSWER Not actually a layer of the skin Supports skin (epidermis and dermis). Areolar and adipose loose connective tissue (mostly adipose). Allows movement of skin over muscle and bones.
Nails - ANSWER Modified stratum corneum Protective Parts:
- Free edge (whitish part)
- Nail body
- Nail root (embedded in skin)
Hair Structure - ANSWER Basic: Shaft (exposed), Root (embedded portion). Hair Follicle: Bulb (innervation), Papilla (blood supply). Arrector Pili Muscle: contraction raises hair, "goosebumps"
Eccrine Sweat Glands - ANSWER Secrete onto surface of skin, allows evaporative cooling. Development: Invaginates from skin surface. Produce 99% water, 1% salts/wastes Acidic; antibacterial properties
Apocrine Sweat Glands - ANSWER Discharge into hair follicles, not body surface. Development: outgrowths from hair follicles Produce complex, odorous molecules Found in armpits/genitals
Modified Sweat Glands - ANSWER Ceruminous: produce earwax Mammary: secrete milk
Sebaceous Glands - ANSWER Multicellular exocrine glands Into hair follicles Secrete oil (sebum) Moisturizes hair and skin blocked hair follicle = acne
Skin Cancer - ANSWER Most common form of cancer. Melanoma: potentionally life-threatening -- cancerous melanocytes grow and spread rapidly thru lymphatic system. A. Asymmetry (irregular shape) B. Border (indistinct) C. Color (mottled) D. Diameter (>5mm is dangerous) E. Elevation (not flat)
Cranial Nerves (IMPORTANT TO HAVE MEMORIZED) - ANSWER 1. Olfactory: SENSORY (1)
- Optic: SENSORY (2)
- Oculomotor: MOTOR (1)
Horcruxes (Hypoglossal- CN XII)
Sensory Nerves - ANSWER 1. Olfactory- Smell (origin: Olfactory epithelium of nose)
- Optic Nerve- Vision (terminates in primary visual cortex)
- Vestibulocochlear- Hearing and balance (Origin: Inner ear, enters brain stem at pons)
Motor Nerves - ANSWER 3. Oculomotor- Moves 4 extrinsic eye muscles
- Trochlear- superior oblique
- Abducens- Lateral rectus (abducts eyes)
- Spinal Accessory Nerve- Motor nerve to trapezius and sternocleidomstoid muscles
- Hypoglossal- Motor to tongue (damage deviates towards affected side)
Both Nerves (sensory and motor) - ANSWER 5. Trigeminal: v1- opthalimic- sensory v2: maxillary- sensory v3: mandibular- sensory and motor to muscles of mastication (sensation to anterior 2/3)
- Facial: Motor to facial expression Sensory: Taste: anterior 2/3 tongue
- Glossopharyngeal: Motor to Stylopharyngeal muscle (swallowing) Sensory- taste to posterior 1/3 tongue, and sensation to 1/3 tongue
- Vagus: Motor to larynx and pharyngeal muscles Sensory- external auditory meatus and laryngophaynx
S/M/B Mnemonics (CN1-CN12) - ANSWER (S)ome (S)ay (M)oney (Matters (B)ut
(M)y (B)rother (S)ays (B)ig (B)rains (M)atter (M)ost
Olfactory (CN I) - ANSWER Sensory: smell Origin: Olfactory epithelium of nose, terminate in posterior olfactory cortex.
Optic (CN II) - ANSWER Sensory: Vision Origin: Retina of eye, terminate in PVC. Technically not a nerve, but a brain tract.
Vestibulocochlear (CN VIII) - ANSWER Sensory: Hearing and equilibrium. Origin: Inner ear, enters BS @ pons.
Oculomotor (CN III) - ANSWER Motor nerve to extrinsic eye muscles Origin: midbrain Also parasympathetic (visceral) Pupils
Trochlear (CN IV) - ANSWER Motor nerve to extrinsic eye muscles Origin: midbrain
Abducens (CN VI) - ANSWER Motor nerve to extrinsic eye muscles
