Anatomy Study Guide - Chapters 9-15 PDF

CHAPTER 9 1. What are joints, how are they named, and what functions do they serve? A joint (articulation) is the point where two bones meet. Joints are named based on the bones they connect and their structural or functional characteristics. Functions: They provide mobility and stability to the...

CHAPTER 9 1. What are joints, how are they named, and what functions do they serve? A joint (articulation) is the point where two bones meet. Joints are named based on the bones they connect and their structural or functional characteristics. Functions: They provide mobility and stability to the skeleton, allowing for body movements and supporting the body’s posture. 2. Name and describe the four major classes of joints: Bony joints (Synostosis): Immovable joints where two bones are fused together (e.g., the mandibular bones in infancy or the first rib to sternum in old age)). Fibrous joints (Synarthrosis): Joints where collagen fibers bind adjacent bones. These joints allow little to no movement (e.g., sutures, gomphoses, syndesmosis)). Cartilaginous joints (Amphiarthrosis): Joints where two bones are linked by cartilage, allowing slight movement (e.g., synchondroses and symphyses)). Synovial joints (Diarthrosis): The most structurally complex and movable joints. They contain a synovial cavity filled with fluid and are often prone to dysfunction). 3. Name some joints that become solidly fused by bone as they age: Examples include the mandibular bones, which fuse in infancy, and the first rib to the sternum, which fuses in old age). 4. Describe the three types of fibrous joints and give an example of each: Sutures: Immobile or slightly movable joints between skull bones. There are three classifications: serrate (interlocked), lap (overlapped), and plane (non-overlapped)). Gomphoses: Joints where a tooth is anchored into its socket by periodontal ligaments. There is slight movement under the stress of chewing). Syndesmoses: Joints where two bones are bound by long collagen fibers, allowing some movement (e.g., the joint between the radius and ulna or tibia and fibula)). 5. Describe the two types of cartilaginous joints and give an example of each: Synchondroses: Joints where bones are bound by hyaline cartilage, such as the epiphyseal plate in growing children or the costal cartilage of the ribs). Symphyses: Joints where bones are joined by fibrocartilage, such as the pubic symphysis and the intervertebral discs). 6. Describe the anatomy of a synovial joint and its associated structures: Articular cartilage: Hyaline cartilage that covers the facing surfaces of bones. Joint capsule: Surrounds the joint cavity, consisting of an outer fibrous capsule and an inner synovial membrane that produces synovial fluid, which lubricates the joint. Fibrocartilage pads like articular discs or menisci (e.g., in the jaw and knee) cushion and support the joint. Tendons connect muscle to bone, and ligaments connect bone to bone. Bursa: A sac of synovial fluid that reduces friction between adjacent muscles, bones, or skin). 7. Describe the six types of synovial joints: Ball-and-socket: Multiaxial joints with movement in multiple directions (e.g., shoulder, hip). Condylar (ellipsoid): Biaxial joints (e.g., wrist). Saddle: Biaxial joints (e.g., the base of the thumb). Plane (gliding): Biaxial joints (e.g., intercarpal joints). Hinge: Monoaxial joints (e.g., elbow, knee). Pivot: Monoaxial joints where a bone rotates on its axis (e.g., the atlantoaxial joint in the neck)). 8. List and demonstrate the types of movements that occur at diarthroses (synovial joints): Flexion: Decreases the joint angle. Extension: Straightens or increases the joint angle. Abduction: Moves a body part away from the midline. Adduction: Moves a body part toward the midline. Circumduction: The distal end of a limb makes a circle while the proximal end remains stationary. Rotation: Bone spins on its long axis (e.g., medial and lateral rotation). Supination: Turns the palm to face anteriorly (e.g., radius and ulna become parallel). Pronation: Turns the palm to face posteriorly (e.g., the radius crosses over the ulna)). 9. Identify the major anatomical features of the jaw, shoulder, elbow, hip, knee, and ankle joints: Jaw Joint (TMJ): A condylar, hinge, and plane joint. Ligaments: lateral ligament). Shoulder Joint: A ball-and-socket joint with ligaments like the coracohumeral and glenohumeral ligaments, and the glenoid labrum (a ring of fibrocartilage)). Elbow Joint: A hinge and pivot joint stabilized by radial collateral and ulnar collateral ligaments). Hip Joint: A ball-and-socket joint with the acetabular labrum (fibrocartilage) deepening the socket and ligaments like iliofemoral, pubofemoral, and ischiofemoral). Knee Joint: A hinge joint with medial and lateral menisci for padding, and ligaments like the anterior cruciate ligament (ACL)). Ankle Joint: A hinge joint with ligaments like the anterior talofibular, posterior talofibular, and the calcaneal (Achilles) tendon). 10. Define arthritis and describe its forms and causes: Arthritis: Inflammation of joints. It is the most common crippling disorder in the U.S. Osteoarthritis (OA): The most common form of arthritis, caused by wear-and-tear. Affects 85% of people over 70. It is characterized by crepitus, or the crunching and cracking sounds in joints. Rheumatoid Arthritis (RA): An autoimmune disease that attacks the synovial membrane, leading to ossification of the cartilage. This results in bones becoming solidly fused, a condition called ankylosis. There is no cure) Chapter 10 1. List the functions of muscular tissue and the properties it must have to carry out these functions. Functions: Movement (body parts, body contents, communication), stability (maintain posture, resist pull of gravity), control of body openings and passages, and heat production. Properties:  Excitability (responsiveness): React to stimuli. Conductivity: Spread electrical impulse through muscle cell. Contractility: Shorten when stimulated. Extensibility: Can stretch without harm. Elasticity: Can recoil from stretch. 2. Describe the distinctions between the three types of muscular tissue. Skeletal Muscle: Voluntary, striated, attached to bone. Muscle cell = muscle fiber or myofiber. Cardiac Muscle: Involuntary, striated, cells = cardiomyocytes. Smooth Muscle: Involuntary, non-striated, fusiform cell shape, tapered at ends. 3. Describe the ultrastructure of a muscle fiber and its myofilaments. Muscle fiber structure includes: Sarcolemma with T-tubules (invaginations of the sarcolemma). Sarcoplasm with myofibrils, glycogen, and myoglobin. Sarcoplasmic reticulum with terminal cisterns (stores calcium for muscle contraction). Myofilaments: Thick myofilaments: Myosin with heads projecting from bundled tails. Thin myofilaments: Actin, with active sites for myosin binding, and regulatory proteins tropomyosin and troponin. 4. Explain what accounts for the striations of skeletal muscle. Striations: Narrow stripes (light and dark) that run perpendicular to the length of the cell, due to alternating bands of thick and thin filaments. 5. Describe the blood supply to a skeletal muscle. At rest, muscle receives about one-quarter of the heart’s output. During heavy exercise, muscle receives more than three-quarters of the heart’s output (a larger percentage of a larger output). Muscle is generally well-vascularized. 6. Describe the neuromuscular junction where a nerve fiber meets a muscle fiber. Neuromuscular junction: Also called a synapse. The motor neuron’s synaptic knob contains vesicles with neurotransmitters that are released into the synaptic cleft, where the postsynaptic membrane folds of the muscle cell contain receptors for the neurotransmitter. 7. Describe the two main types of muscle fibers and their respective advantages and disadvantages. Not specified in the slides, but inferred: Slow-twitch fibers (high endurance, oxidative) and fast-twitch fibers (rapid contraction, anaerobic). 8. Describe how a muscle grows and shrinks with use and disuse. Resistance exercise stimulates the production of more myofilaments, leading to growth by hypertrophy (not hyperplasia, as muscle fibers do not undergo mitosis). Exercise also stimulates the production of mitochondria, myoglobin, glycogen, and blood vessels. Unused muscles atrophy (shrink). 9. Describe cardiac muscle tissue and compare its structure and physiology to the other types. Cardiac Muscle: Striated, short, stumpy, branched cells, with intercalated discs containing gap junctions. Typically mononucleated and involuntary. 10. Describe smooth muscle tissue and compare its structure and physiology to the other types. Smooth Muscle: No striations, small fusiform cell with one nucleus, dense bodies linking cytoskeleton and membrane. Involuntary control. Can be multiunit (independent control) or unitary (several cells excited at once). 11. Describe the changes that occur in the muscular system in old age. Not explicitly covered in the slides. 12. Discuss diseases: muscular dystrophy, myasthenia gravis. Muscular dystrophy: Hereditary, caused by a defective gene for dystrophin (a muscle protein), leading to skeletal muscle degeneration. Myasthenia gravis: An autoimmune disease where the immune system destroys muscle neurotransmitter receptors.  13. Briefly define and discuss several other disorders of the muscular system. The slides focus on myopathies such as muscular dystrophy and myasthenia gravis. Other disorders may include general muscle conditions but are not detailed in the provided slides. Chapter 11 1. Name and describe the connective tissues surrounding each component of a muscle. Epimysium – wraps muscle Perimysium – wraps fascicle Endomysium – wraps cell . 2. Describe how muscles are classified by shape and by the orientation of their fibers. Fusiform muscles: Thick in middle, tapered at ends. Parallel muscles: Uniform width, fascicles aligned. Triangular muscles: Broad at one end, narrow at other end. Pennate muscles: Feather-shaped. Circular muscles (sphincters): Form rings around body openings . 3. Describe two basic modes of muscle—bone attachment. What is an aponeurosis? Direct (fleshy) attachment: Close association with bone. Indirect attachment: Tendon attaches muscle to bone. Aponeurosis: Broad sheet of tendon . 4. Contrast the roles of a prime mover, synergist, antagonist, and fixator muscle in producing and controlling movement at a joint. Prime mover (agonist): Produces main force of action. Synergist: Aids prime mover. May stabilize joint. Antagonist: Opposes prime mover.  Fixator: Prevents bone movement . 5. Know the several Latin words commonly used in the naming of muscles. Size: For example, “brevis” = short. Shape: For example, “teres” = round. Location: For example, “brachii” = of the arm. Number of heads: For example, “biceps” = two heads. Orientation of the fibers: For example, “rectus” = straight. Action: For example, “flexor” = a muscle that flexes . 6. Define the innervation of a muscle. Innervation: Describes which nerve stimulates the muscle. Spinal nerves arise from the spinal cord and innervate muscles below the neck. Cranial nerves emerge from the brainstem and innervate muscles of the head and neck . 7. Name and locate the muscles that produce facial expressions. Frontal belly of occipitofrontalis elevates eyebrows. Orbicularis oculi closes eyes. Zygomaticus major and minor raise corners of mouth for smile. Risorius expresses horror . 8. Name and locate the muscles used for chewing and swallowing. Temporalis and masseter elevate mandible and move it sideways. Buccinator depresses cheeks against teeth keeping food central in the mouth . 9. Name and locate the neck muscles that move the head. Sternocleidomastoid rotates head to side when unilaterally active, draws head forward when bilaterally active . 10. Name and locate the muscles of respiration.  Diaphragm is the prime mover of inspiration. External Intercostals are muscles of inspiration. Internal Intercostals are muscles of expiration . 11. Name and locate the muscles of the abdominal wall and back. Rectus abdominis: long, anterior muscle connecting sternum to pubic bone. External oblique: superficial, lateral muscle. Internal oblique: deep to external oblique. Transverse abdominis: deepest of lateral muscles . Chapter 12 1. Explain what muscle compartments are and describe how they are separated from each other. Compartments are spaces enclosed by fasciae called intermuscular septa. Each compartment contains one or more functionally related muscles, along with nerves and blood vessels. 2. Name and locate the muscles that act on the shoulder, arm, forearm, wrist, and hand. Muscles acting on the arm (anterior): Pectoralis major flexes, adducts, and medially rotates humerus. Deltoid can flex and medially rotate, abduct, or extend and laterally rotate the arm, depending on which fibers are active. Coracobrachialis can flex the arm and pull it towards the trunk. Muscles acting on the arm (posterior): Teres major extends and medially rotates humerus. Latissimus dorsi adducts and medially rotates humerus, extends shoulder joint. Rotator cuff muscles: Tendons of four muscles form the rotator cuff: Supraspinatus, Infraspinatus, Teres minor, Subscapularis. Muscles acting on the forearm: Brachialis is the prime mover of elbow flexion. Biceps brachii supinates forearm and flexes both elbow and shoulder. Brachioradialis flexes the elbow. Triceps brachii extends the elbow.  Muscles of the forearm: Anterior compartment muscles flex the wrist (carpus), fingers (digits), and thumb (pollex). Posterior compartment muscles extend the wrist (carpus), fingers (digits), and thumb (pollex). 3. Relate the actions of these muscles to the joint movements. Pectoralis major: Flexes, adducts, and medially rotates the humerus at the shoulder joint. Deltoid: Flexes, abducts, extends, and rotates the arm at the shoulder joint depending on active fibers. Coracobrachialis: Flexes the arm and pulls it towards the trunk at the shoulder joint. Biceps brachii: Supinates the forearm, flexes the elbow and shoulder joints. Triceps brachii: Extends the elbow joint. 4. Describe the attachments and innervation of each muscle. Pectoralis major: Attaches to the clavicle, sternum, and humerus. Deltoid: Attaches to the clavicle, acromion, and scapular spine. Brachialis: Attaches to the anterior surface of the humerus and coronoid process of the ulna. Biceps brachii: Attaches to the scapula and radial tuberosity. Triceps brachii: Attaches to the humerus and ulna. 5. Name and locate the muscles that act on the hip, knee, ankle, and toe joints. Muscles acting on the hip and femur: Iliopsoas consists of the Iliacus and Psoas major, both of which flex the thigh. The medial compartment of the thigh contains the Adductor muscles (magnus, brevis, longus) and Pectineus. Anterior muscles of the thigh: Quadriceps femoris extends the knee and consists of four muscles: Rectus femoris, Vastus lateralis, Vastus medialis, and Vastus intermedius. Posterior gluteal muscles: Gluteus maximus extends and abducts the thigh. Gluteus medius and Gluteus minimus abduct and medially rotate the thigh.  Muscles acting on the leg: All anterior compartment muscles dorsiflex the foot and extend the toes. Posterior compartment muscles plantar flex the foot and flex the toes. 6. Relate the actions of these muscles to the joint movements. Iliopsoas: Flexes the thigh at the hip joint. Quadriceps femoris: Extends the knee joint. Gluteus maximus: Extends and abducts the thigh at the hip joint. Tibialis anterior: Dorsiflexes the ankle joint and extends the toes. Gastrocnemius: Plantar flexes the ankle joint and flexes the toes. 7. Describe the attachments and innervation of each muscle. Quadriceps femoris: Attaches to the anterior inferior iliac spine and tibial tuberosity. Hamstrings: Attach to the ischial tuberosity and bones of the leg. Tibialis anterior: Attaches to the lateral condyle of the tibia and medial cuneiform. Gastrocnemius: Attaches to the femur and calcaneus via the Achilles tendon. 8. Explain how to reduce the risk of muscle injuries. Muscle injuries often result from sudden, intense stress. Risk increases with improper conditioning or inadequate warm-up. Initial remedies involve rest, ice, compression, and elevation (RICE). 9. Define several types of muscle injuries often incurred in sports and recreation. Pitcher’s arm: Inflammation at the attachments of the wrist flexors. Blocker’s arm: Abnormal calcification in the lateral margin of the forearm resulting from repeated impact seen in football. Shin splints: Pain in the crural region caused by tendinitis of the tibialis posterior and inflammation of the periosteum. Tennis elbow: Inflammation at the attachment of extensor carpi muscles that attach to the lateral epicondyle. Chapter 13 Describe the function of the nervous system: "Nervous system functions include sensory perception, integration, and motor planning." Describe the anatomical subdivisions of the nervous system: "Two main divisions: Central nervous system (CNS) – Contains the brain and spinal cord. Peripheral nervous system (PNS) – Contains nerves and ganglia." Explain the functional differences between these anatomical subdivisions: "Central nervous system (CNS) – Contains the brain and spinal cord. Peripheral nervous system (PNS) – Contains nerves and ganglia." Define nerve, ganglion, receptor, and effector: The slides don't provide a direct definition of receptor and effector, but mention the nerve as part of the PNS and ganglion as containing neuron cell bodies in the PNS. Describe the properties that neurons must have to carry out their function: "Nerve cell = neuron with three fundamental properties: Excitability (irritability) – can respond to stimuli. Conductivity – can send signals to distant locations quickly. Secretion – can release chemical messengers (neurotransmitters)." Define three functional classes into which all neurons fall: "Sensory (afferent) neurons – Detects the stimuli. Interneurons – Receive signals from other neurons and make decisions about the response. Motor (efferent) neurons – Send signals to muscles to provide a response." Describe the structure of a representative neuron: "Neurosoma (Soma or cell body) – control center.  Dendrites – receive signals. Axon – sends action potentials (electrochemical messages). Axon terminal (terminal button) – ending of axon branches that communicates with another cell." Describe some variations in neuron structure: "Named for the number of dendrites and axons at the neurosoma: Multipolar – many dendrites, one axon. Bipolar – one dendrite, one axon. Unipolar – no dendrites, one axon." Name six types of cells that aid neuron function and state their respective locations and functions: CNS glia: "Oligodendrocytes myelinate axons to assist with conduction of impulse." "Ependymal cells secrete and circulate cerebrospinal fluid." "Microglia help in defense and disposal." "Astrocytes provide support and nourishment." PNS glia: "Schwann cells myelinate axons to assist with conduction of impulse." "Satellite cells provide support and nourishment." Describe the myelin sheath that is formed around certain nerve fibers: "Oligodendrocytes make myelin in the CNS. Schwann cells make myelin in the PNS." Describe the synaptic junctions between one neuron and another: "Synapses: Meeting point of neuron and neuron or with other cell types. Presynaptic neuron to postsynaptic neuron." Describe the variety of interconnections that exist between two neurons: "Axodendritic synapse – Axon to dendrite. Axosomatic synapse – Axon to neurosoma. Axoaxonic synapse – Axon to axon." Describe two basic variations (converging and diverging) in the circuitry or "wiring patterns" of the nervous system: Not explicitly mentioned in the slides, but typically, converging circuits involve multiple inputs converging onto a single neuron, and diverging circuits involve one input spreading to multiple outputs. Chapter 14 Describe the functions of the spinal cord: Not explicitly defined in the provided slides, but the spinal cord is typically involved in transmitting signals between the brain and the rest of the body, as well as coordinating reflexes. Describe the surface and cross-sectional anatomy of the cord: "Surface Anatomy of the Spinal Cord: Regions: Cervical, Thoracic, Lumbar, Sacral. Enlargements: Cervical, Lumbosacral. Medullary cone, Cauda equina, Terminal filum." "Cross-Sectional Anatomy: Fissure/Sulcus: Anterior median fissure, Posterior median sulcus. Central canal: Runs down the center of spinal cord, Contains cerebrospinal fluid (CSF)." Explain the difference between the gray and white matter of the cord: "Gray matter: Contains very few myelinated axons, Always contains two posterior (dorsal) horns and two anterior (ventral) horns." "White matter: Contains the myelinated axons, Three pairs of columns (funiculi) containing tracts (fasciculi) – Posterior (dorsal), lateral, and anterior (ventral) columns." Identify the major pathways (tracts) that conduct signals up and down the spinal cord, and identify the types of signals they carry:  "Ascending tracts carry sensory info to the brain. Descending tracts carry motor info from brain. Many tracts decussate or cross the midline." Describe the anatomy of nerves and ganglia in general: "A nerve is several axons wrapped by connective tissue. Epineurium wraps entire nerve. Perineurium wraps a fascicle of axons. Endoneurium wraps one axon." "A ganglion is a cluster of cell bodies outside the CNS." Describe the attachment of a spinal nerve to the spinal cord: "Proximal branches (closest to Spinal Cord): Posterior (Dorsal) root, Posterior (Dorsal) root ganglion, Anterior (Ventral) root." Trace the branches of a generalized spinal nerve distal to its attachment: "Distal Branches (further from Spinal Cord): Posterior (Dorsal) ramus, Anterior (Ventral) ramus." Name the five plexuses of spinal nerves and describe their general anatomy: "Cervical plexus – in neck, Brachial plexus – in shoulder, Lumbar plexus – in lower back, Sacral plexus – below lumbar, Coccygeal plexus – lower sacrum and coccyx." Name some major nerves (see lecture slides) that arise from each plexus and identify what they innervate: "Cervical Plexus: Phrenic Nerve – Innervates the diaphragm for breathing." "Sacral and Coccygeal Plexuses: Common Fibular + Tibial Nerves = Sciatic Nerve." Explain the relationship of dermatomes to the spinal nerves: "Dermatome – area of skin innervated by a particular spinal nerve. Dermatome map: Diagram of the areas of skin innervated by each spinal nerve." Describe some effects of spinal cord injuries: "Paraplegia: Paralysis of both lower limbs due to lesions from T1 to L1. Quadriplegia: Paralysis of all four limbs due to lesions above C5 and likely ventilation support. Hemiplegia: Paralysis on one side of body usually due to stroke or brain lesions." Define the types of paralysis and explain the basis for their differences: "Paraplegia: Paralysis of both lower limbs. Quadriplegia: Paralysis of all four limbs. Hemiplegia: Paralysis on one side of body." Chapter 15 Describe the major subdivisions and anatomical landmarks of the brain: "Cerebrum: Two cerebral hemispheres which contain: Gyri – folds, Sulci – grooves, Longitudinal cerebral fissure – big sulcus between hemispheres. Cerebellum: Also has folds. Brainstem: Crucial for survival" State the locations of the gray and white matter of the brain: "Gray Matter: Outer part (cortex) of cerebrum and of cerebellum. Neurosomas, dendrites, unmyelinated axons, and synapses" "White Matter: Deep in brain. Contain tracts made up of bundles of myelinated axons" Describe the meninges of the brain: "Dura mater – tough, outer layer. Arachnoid mater – transparent, middle layer, CSF, arachnoid granulations. Pia mater – delicate, inner layer" Describe the system of fluid-filled chambers within the brain: "Lateral ventricles (2), Third ventricle (1), Fourth ventricle (1), Central Canal of Spinal Cord" Discuss the production, flow, and function of the cerebrospinal fluid in these chambers: "Cerebrospinal fluid (CSF): Clear, colorless liquid. Produced by choroid plexus (ependymal cells) within the ventricles. Flows within ventricles, down canals, and within subarachnoid space of the brain and spinal cord. Absorbed by arachnoid granulations back into blood at superior sagittal sinus. Provides buoyancy, protection, and chemical stability" Explain the significance of the brain barrier system:  The slides do not explicitly mention the brain barrier system in this section. However, it is usually described as protecting the brain by regulating which substances can enter the brain tissue from the bloodstream. List the components of the hindbrain and midbrain: "Brainstem: The brain stem is composed of the: Midbrain, Pons, Medulla oblongata" Describe the major features of their anatomy: "The Pons: Anterior aspect creates a large bulge containing longitudinal and transverse fascicles. Posterior aspect: contains peduncles that attach to cerebellum" "The Midbrain: Tectum (posterior aspect): Tectal plate (corpora quadrigemina) – four bulges consisting of superior and inferior colliculi" "The Medulla Oblongata: Extends from the pons to the foramen magnum of the skull (where it becomes the spinal cord)" Explain the functions of each hindbrain and midbrain region: "Pons: Contains various tracts between the spinal cord and the brain/cerebellum" "Midbrain: Substantia nigra – degenerates leading to Parkinson’s" "Medulla Oblongata: Contains cardiac center, vasomotor center, respiratory center" Name the three major components of the diencephalon and describe their locations and functions: "Thalamus: 'Sensory gateway to the cerebral cortex.' All sensory input except for smell goes through here. Also involved in memory and emotion" "Hypothalamus: Major control center of the autonomic nervous system and endocrine system" "Epithalamus: Pineal gland – an endocrine gland" Locate the five lobes of the cerebrum and identify their functions: "Frontal lobe: Cognition, speech, and motor control" "Parietal lobe: Interprets signals of general senses and taste" "Occipital lobe: Principal visual center" "Temporal lobe: Hearing, smell, learning, and memory" "Insula: Taste, visceral sensation, and language" Describe the three types of tracts in the cerebral white matter:  "Projection tracts: Travel vertically to carry information between cerebrum and rest of body" "Commissural tracts: Commissures cross between two hemispheres. Corpus callosum is largest" "Association tracts: Connect regions within same hemisphere" Describe the distinctive cell types and histological arrangement of the cerebral cortex: "The Cerebral Cortex: Contains pyramidal cells. Triangle shaped with apex pointing to brain surface" Discuss the locations and functions of the basal nuclei and limbic systems: "Basal Nuclei: Deep masses of cerebral gray matter. Involved in motor control" "Limbic System: Important functions for emotion and learning" List the 12 cranial nerves by name and number: "I Olfactory, II Optic, III Oculomotor, IV Trochlear, V Trigeminal, VI Abducens, VII Facial, VIII Vestibulocochlear, IX Glossopharyngeal, X Vagus, XI Accessory, XII Hypoglossal" State the functions of each cranial nerve: "I Olfactory: Sensory nerve for smell" "II Optic: Sensory nerve for vision" "III Oculomotor: Motor nerve for Superior, Inferior, and Medial Recti, as well as the Inferior Oblique eye muscles" "IV Trochlear: Motor nerve for the Superior Oblique eye muscle only" "V Trigeminal: Mixed nerve (BOTH motor and sensory) for sensation of the face and control of chewing movements" "VI Abducens: Motor nerve for the Lateral Rectus eye muscle only" "VII Facial: Mixed nerve (BOTH) for sensation of taste and control of expressions, facial secretions" "VIII Vestibulocochlear: Sensory nerve for hearing and equilibrium" "IX Glossopharyngeal: Mixed nerve (BOTH) with diverse sensory and motor functions for head, neck, and thorax" "X Vagus: Mixed nerve (BOTH) for taste, gastrointestinal sensation, and control of various other visceral organs"  "XI Accessory: Motor nerve for swallowing, head, neck, and shoulder movements (Trapezius and Sternocleidomastoid muscle)" "XII Hypoglossal: Motor nerve controlling movements of the tongue" Discuss Alzheimer's and Parkinson's diseases at the levels of neurotransmitter function and brain anatomy: "Alzheimer disease (AD): Atrophy of gyri of cerebral cortex and hippocampus. Neurofibrillary tangles and senile plaques" "Parkinson disease (PD): Loss of motor function (tremors, shuffling gait, difficulty with movement sequences). Degeneration of dopamine-releasing cells from substantia nigra"