Group 2 Muscles and Nervous Tissues PDF

GROUP 2 - 2103 MUSCLE TISSUE MUSCLE TISSUE LOCATION TYPE OF CELLS HISTOLOGY PRIMARY TISSUE TYPES OF THE BODY. PRODUCE A FORM OF MOVEMENT. BONES, JOINTS, SKIN, HEART, INTERNAL STRUCTURES, BLOOD VESSELS, EYES AND BODY PASSAGEWAYS. CHARACTERISTICS OF MU...

GROUP 2 - 2103 MUSCLE TISSUE MUSCLE TISSUE LOCATION TYPE OF CELLS HISTOLOGY PRIMARY TISSUE TYPES OF THE BODY. PRODUCE A FORM OF MOVEMENT. BONES, JOINTS, SKIN, HEART, INTERNAL STRUCTURES, BLOOD VESSELS, EYES AND BODY PASSAGEWAYS. CHARACTERISTICS OF MUSCLE TISSUE 1. EXCITABILITY 2. CONTRACTILITY 3. EXTENSIBILITY 4. ELASTICITY  CARDIAC MUSCLE LOCATION TYPE OF CELLS HISTOLOGY CARDIOMYOCYTES (CARDIAC MUSCLE FIBERS) MUCH SMALLER, SHORTER AND EXTENSIVELY BRANCHED THAN SKELETAL MUSCLE FIBERS CAN BE FOUND IN THE HEART CIRCULATION OF BLOOD INTERCALATED DISCS WITH GAP JUNCTIONS  SMOOTH MUSCLE LOCATION TYPE OF CELLS HISTOLOGY SMALL SPINDLED MUSCLE SHAPE SHORTER THAN SKELETAL MUSCLE FIBERS. CAN BE FOUND ON THE WALLS OF SOME INTERNAL ORGANS AND PASSAGEWAYS. MOVE FOOD, URINE, REPRODUCTIVE SECRETIONS THROUGH THEIR RESPECTIVE SYSTEMS CAN ALSO DIVIDE TO PRODUCE MORE CELLS, A PROCESS CALLED HYPERPLASIA  SKELETAL MUSCLE LOCATION TYPE OF CELLS HISTOLOGY LONG, CYLINDRICAL FIBERS CAN BE FOUND IN THE MUSCLES OF THE LIMBS, TRUNK, FACIAL EXPRESSION, AND EXTERNAL SPHINCTERS MOVEMENT OR STABILIZATION OF THE SKELETON, GUARD ENTRANCES AND/OR EXITS FOR THE DIGESTIVE, RESPIRATORY, AND URINARY SYSTEM MORE ABOUT SKELETAL MUSCLE SKELETAL MUSCLE FIBERS CAN BE QUITE LARGE, SPANNING THE ENTIRE LENGTH OF THE MUSCLE. THE NUMBER OF SKELETAL MUSCLE FIBERS IS SET DURING DEVELOPMENT AND STAYS RELATIVELY CONSTANT THROUGHOUT LIFE, AS SKELETAL MUSCLE FIBERS CANNOT DIVIDE TO PRODUCE MORE FIBERS. SKELETAL MUSCLE PRODUCES MOVEMENT THROUGH VOLUNTARY CONTRACTION  KEY FUNCTION OF SKELETAL MUSCLE MAINTAIN POSTURE AND STABILIZE JOINTS CONTRACTION ALLOWS US TO MAINTAIN OUR POSTURE, RESIST GRAVITY AND ADDS DYNAMIC STABILITY TO OUR JOINTS GENERATE HEAT SKELETAL MUSCLE GENERATES HEAT AS A BYPRODUCT OF ITS CONTRACTION. PROTECT INTERNAL ORGANS FORMS A PHYSICAL BARRIER BETWEEN OUR INTERNAL ORGANS AND THE OUTSIDE WORLD. SKELETAL MUSCLE FIBERS MUSCLE FIBERS ARE ORGANIZED INTO INDIVIDUAL BUNDLES, CALLED FASCICLES. EACH SKELETAL MUSCLE HAS THREE LAYERS OF CONNECTIVE TISSUE THAT ENCLOSE IT, PROVIDES STRUCTURE AND SUPPORT TO THE MUSCLE AS A WHOLE, AND COMPARTMENTALIZE THE MUSCLE FIBERS WITHIN THE MUSCLE. EPIMYSIUM PERIMYSIUM ENDOMYSIUM SKELETAL MUSCLE FIBERS MYOFIBRILS - EACH MYOFIBRIL RUNS THE ENTIRE LENGTH OF THE MUSCLE FIBER. MYOFILAMENTS - WHICH ARE ACTIN AND MYOSIN PROTEINS. ACTIN AND MYOSIN - ORGANIZED INTO REPETITIVE GROUPINGS, AND EACH UNIQUE GROUPING IS CALLED A SARCOMERE. SARCOMERE - FUNCTIONAL UNIT OF THE MUSCLE FIBER. MOTOR UNITS MOTOR UNITS IS THE GROUP OF MUSCLE FIBERS IN A MUSCLE INNERVATED BY A SINGLE MOTOR NEURON EACH MUSCLE FIBER IS CONNECTED TO ONLY ONE MOTOR NEURON, BUT A MOTOR NEURON CAN CONTROL MULTIPLE FIBERS. NEUROMUSCULAR JUNCTION IS THE SITE WHERE THE MOTOR NEURON MEETS THE MUSCLE FIBER. MOTOR UNITS THE SIZE OF A MOTOR UNIT IS VARIABLE DEPENDING ON THE NATURE OF THE MUSCLE. SMALL MOTOR UNIT - ONE MOTOR NEURON SUPPLIES A SMALL NUMBER OF FIBERS IN A MUSCLE. LARGE MOTOR UNIT - ONE MOTOR NEURON SUPPLIES A LARGE NUMBER OF MUSCLE FIBERS IN A MUSCLE.  MOTOR UNITS MAXIMUM CONTRACTION ALL OR NONE PRINCIPLE AND FATIGUE WHEN A MOTOR NEURON IS WHEN ALL MOTOR UNITS ARE STIMULATED, ALL FIBERS IN ITS RECRUITED SIMULTANEOUSLY, IT MOTOR UNIT CONTRACT FULLY. CREATES MAXIMUM FORCE. THIS PRINCIPLE ENSURES THAT ALL THIS LEVEL OF FORCE IS FIBERS IN A MOTOR UNIT RESPOND UNSUSTAINABLE DUE TO HIGH FULLY TO STIMULATION, NOT ENERGY REQUIREMENTS, WHICH PARTIALLY. CAN LEAD TO FATIGUE. TYPES OF SKELETAL FIBER MUSCLE TYPES OF SKELETAL FIBER MUSCLE SLOW OXIDATIVE (SO) FAST OXIDATIVE (FO) FAST GLYCOLYTIC (FG) FIBERS FIBERS FIBERS CONTRACT SLOWLY INTERMEDIATE SPEED OF CONTRACT QUICKLY USE OXYGEN (AEROBIC) CONTRACTION PRIMARILY USE HIGH ENDURANCE, PRIMARILY USE OXYGEN GLUCOSE (ANAEROBIC) LOWER POWER BUT CAN SWITCH TO HIGH POWER, LOW FUNCTION WELL FOR GLUCOSE ENDURANCE POSTURAL CONTROL MODERATE ENDURANCE, AND ISOMETRIC MODERATE POWER EX. POWERFUL, RAPID CONTRACTIONS MOVEMENTS EX. MOVEMENTS EX. ENDURANCE ACTIVITIES DISTRIBUTION OF MUSCLE FIBERS MOST MUSCLES CONTAIN A MIX OF SLOW OXIDATIVE , FAST OXIDATIVE, AND FAST GLYCOLYTIC FIBERS. THE PRIMARY FUNCTION OF THE MUSCLE INFLUENCES MUSCLE FIBER TYPE. ENDURANCE-ORIENTED MUSCLES HAVE MORE SLOW OXIDATIVE FIBERS. POWER-ORIENTED MUSCLES HAVE MORE FAST GLYCOLYTIC FIBERS. NERVOUS TISSUE NERVOUS TISSUE TRANSMITS AND RECEIVES ELECTROCHEMICAL SIGNALS THAT PROVIDE THE BODY WITH INFORMATION TYPES OF NERVOUS TISSUE: WHITE MATTER — CONSISTS PRIMARILY OF SIGNAL-SENDING AXONS OF NEURONS, TOGETHER WITH THE NEUROGLIAL CELLS WRAPPED AROUND THEM. IT OCCURS IN THE BRAIN'S INTERIOR. GRAY MATTER — INCLUDES OTHER TYPE OF NEUROGLIA, TOGETHER WITH THE MOST NEURON CELL BODIES AND THEIR SIGNAL-RECEIVING DENDRITES. IT IS FOUND AT THE BRAIN'S OUTER SURFACE.  1. THE CENTRAL NERVOUS SYSTEM (CNS) CONSISTS OF THE BRAIN AND SPINAL NERVOUS SYSTEM’S CORD. 2. THE PERIPHERAL NERVOUS SYSTEM (PNS) TWO MAJOR REGIONS: CONSISTS OF ALL NERVOUS TISSUE OUTSIDE OF THE BRAIN AND SPINAL CORD. 1. NEURONS PROCESS AND COMMUNICATE TWO MAIN CLASSES OF INFORMATION THROUGHOUT THE BODY. CELLS MAKE UP 2. GLIAL CELLS, OR NEUROGLIA, PLAY AN NERVOUS TISSUE: ESSENTIAL ROLE IN SUPPORTING NEURONS. NEURONS TRANSMIT INFORMATION THROUGH THE BODY VIA ELECTROCHEMICAL SIGNALS HAS MORE THAN 100 BILLION NEURONS THREE TYPES OF NEURONS: SENSORY NEURONS — ARE EXCITED BY SPECIFIC STIMULI, SUCH AS LIGHT OR PRESSURE. INTERNEURONS — RECEIVE AND INTEGRATE SENSORY INFORMATION. THEY COORDINATE RESPONSES TO STIMULI AND FUNCTION IN MEMORY MOTOR NEURONS — RELAY COMMANDS FROM THE BRAIN AND SPINAL CORD TO GLANDS AND MUSCLE CELLS. PARTS OF NEURON THREE MAIN PARTS OF NEURON CELL BODY INCLUDES MOST OF THE CYTOPLASM, THE ORGANELLES, AND THE NUCLEUS. IT IS THE PROCESSING OR “THINKING” PART OF THE NEURON THREE MAIN PARTS OF NEURON DENDRITES THESE BRANCHES RECEIVE MOST OF THE INPUT FROM OTHER NEURONS AND CARRY IT TO THE CELL BODY. THREE MAIN PARTS OF NEURON AXON A FIBER THAT EMERGES FROM THE CELL BODY AND PROJECTS TO TARGET CELLS. IT IS THE AXON THAT PROPAGATES THE NERVE IMPULSE, WHICH IS COMMUNICATED TO ONE OR MORE CELLS.  SHAPES OF NEURONS PSEUDOUNIPOLAR CELLS HAVE AN AXON THAT EMERGES FROM THE CELL BODY, BUT IT SPLITS SO THAT THE AXON CAN EXTEND ALONG A VERY LONG DISTANCE. AT ONE END OF THE AXON ARE DENDRITES, AND AT THE OTHER END, THE AXON FORMS SYNAPTIC CONNECTIONS WITH A TARGET. UNIPOLAR NEURON  SHAPES OF NEURONS EXTEND FROM EACH END OF THE CELL BODY, OPPOSITE TO EACH OTHER. ONE IS THE AXON AND ONE THE DENDRITE. THEY ARE FOUND MAINLY IN THE OLFACTORY EPITHELIUM (WHERE SMELL STIMULI ARE SENSED), AND BIPOLAR NEURON AS PART OF THE RETINA.  SHAPES OF NEURONS ARE ALL OF THE NEURONS THAT ARE NOT UNIPOLAR OR BIPOLAR. THEY ARE BY FAR THE MOST COMMON NEURONS IN THE BODY. THEY HAVE ONE AXON AND TWO OR MORE DENDRITES MULTIPOLAR NEURON GLIAL CELLS OF THE CENTRAL NERVOUS SYSTEM ASTROCYTES THE MOST ABUNDANT GLIAL CELLS IN THE CNS. NAMED FOR THEIR STAR SHAPE. THEY HAVE MANY PROCESSES EXTENDING FROM THEIR MAIN CELL BODY. ASTROCYTES HAVE MANY FUNCTIONS, MOST OF WHICH SERVE TO SUPPORT NEURONS, INCLUDING: REGULATE THE ENVIRONMENT AROUND NEURONS AND TAKES UP AND BREAKS DOWN SOME NEUROTRANSMITTERS OR IONS IN THE FLUID SURROUNDING THE NEURONS. CONTRIBUTE TO THE BLOOD-BRAIN BARRIER ACT LIKE THE CONNECTIVE TISSUE OF THE BRAIN, FILLING SPACES AND HOLDING THINGS TOGETHER. FORM SCAR TISSUE OF THE BRAIN BY PROLIFERATING AND SURROUNDING DAMAGED REGIONS TO SEPARATE IT FROM THE HEALTHY NEURONS. REGULATE THE INFLAMMATORY RESPONSE TO DAMAGE. INVOLVED IN SYNAPSE FORMATION AND NEURONAL GROWTH IN DEVELOPING NERVOUS TISSUE. PROPAGATE CALCIUM SIGNALS INVOLVED WITH MEMORY.  MICROGLIA THE SMALLEST AND LEAST - ABUNDANT IN THE CNS. CAN BE CONSIDERED THE IMMUNE CELLS OF THE BRAIN. CONSTANTLY PATROLLING THE CNS, EXTENDING AND RETRACTING THEIR PROCESSES TO INSPECT THE BRAIN AND SPINAL CORD TISSUE. IF THERE IS DAMAGE TO NERVOUS TISSUE IN THE CNS, CHEMICALS ARE SENSED BY THE MICROGLIA AND DRAW THEM TO THE INJURY SITE. OLIGODENDROCYTES MYELINATE AXONS IN THE CENTRAL NERVOUS SYSTEM. CONTAIN A FEW PROCESSES, EACH EXTENDING OUT FROM THE CELL BODY TO MYELINATE A PORTION OF AN AXON. ONE OLIGODENDROCYTE WILL PROVIDE THE MYELIN FOR MULTIPLLE AXON SEGMENTS, EITHER FOR THE SAME AXON OR FOR SEPARATE AXONS. EPENDYMAL CELLS FILTER BLOOD TO MAKE CEREBROSPINAL FLUID (CSF), THE FLUID THAT CIRCULATES THROUGH THE CNS. THEY LINE EACH VENTRICLE, THE OPEN SPACES IN THE BRAIN, AND THE CILIA ON THEIR SURFACE HELP TO MOVE CSF THROUGH CNS.  GLIAL CELLS OF THE PERIPHERAL NERVOUS SYSTEM SCHWANN CELLS THEY MYELINATE AXONS IN THE PERIPHERY A SCHWANN CELL WRAPS ITS ENTIRE SELF AROUND ONE PART OF ONLY ONE AXON SEGMENT. SATELLITE CELLS THESE GLIAL CELLS SURROUND THE CELL BODIES OF NEURONS IN THE PNS, ISOLATING THEM AND PROTECTING THEM FROM THE SURROUNDING TISSUE. PROVIDE SUPPORT, PERFORMING SIMILAR FUNCTIONS IN THE PERIPHERY AS ASTROCYTES DO IN THE CNS. MYELINATION  MYELIN IS A LIPID-RICH SHEATH THAT SURROUNDS THE AXON AND CREATES A MYELIN SHEATH THAT FACILITATES THE TRANSMISSION OF ELECTRICAL SIGNALS ALONG THE AXON. MYELIN ACTS AS INSULATION MUCH LIKE THE PLASTIC OR RUBBER THAT IS USED TO INSULATE ELECTRICAL WIRES. THERE ARE GAPS IN THE MYELIN COVERING OF AN AXON. EACH GAP IS CALLED A NODE OF RANVIER AND ASSISTS WITH THE SPEED OF CONDUCTION ALONG AN AXON. MYELINATION OCCURS: IN THE CNS (CENTRAL NERVOUS SYSTEM), CELLS CALLED OLIGODENDROCYTES WRAP SECTIONS OF THE AXON IN LAYERS OF MYELIN. IN THE PNS (PERIPHERAL NERVOUS SYSTEM), SCHWANN CELLS WRAP THEMSELVES COMPLETELY AROUND THE AXON. THICKER MYELIN = FASTER SIGNALS NOT ALL AXONS ARE MYELINATED, AND UNMYELINATED AXONS HAVE THE SLOWEST CONDUCTION SPEED. TERMINOLOGY: COLLECTIONS OF CELL BODIES OR AXONS A GROUP OF NEURONAL CELL BODIES: CNS = NUCLEUS PNS = GANGLION (GANGLIA IS PLURAL) BUNDLE OF AXONS (FIBERS) CNS = TRACT (MOST COMMON), ALSO FASCICLE, LEMNISCUS, COMMISSURE PNS = NERVE  EPINEURIUM: THE OUTER LAYER NERVES ARE COMPOSED OF MORE THAN JUST THAT COVERS THE ENTIRE NERVOUS TISSUE. THEY HAVE CONNECTIVE NERVE. TISSUES INVESTED IN THEIR STRUCTURE, AS WELL AS BLOOD VESSELS SUPPLYING THE PERINEURIUM: THIS LAYER TISSUES WITH NOURISHMENT. WRAPS AROUND GROUPS OF AXONS WITHIN THE NERVE, FORMING BUNDLES CALLED FASCICLES. ENDONEURIUM: THE INNERMOST LAYER THAT WRAPS AROUND INDIVIDUAL AXONS. THESE THREE LAYERS ARE SIMILAR TO THE CONNECTIVE TISSUE SHEATHS FOR MUSCLES. FUNCTIONAL CLASSIFICATIONS IN THE NERVOUS SYSTEM FUNCTIONAL CLASSIFICATIONS IN THE NERVOUS SYSTEM THE NERVOUS SYSTEM IS INVOLVED IN RECEIVING INFORMATION (SENSATION) AND GENERATING RESPONSES (MOTOR RESPONSES). SENSORY INFORMATION TRAVELS FROM THE PERIPHERY TO THE CNS VIA A SENSORY NEURON (AFFERENT FIBERS). THE RESPONSE OCCURS AS MOTOR OUTPUT VIA A MOTOR NEURON THAT ORIGINATES IN THE CNS AND TRAVELS TO EITHER A MUSCLE OR GLAND (EFFERENT FIBERS). NEURAL MODALITIES NEURAL MODALITIES NEURAL MODALITIES ARE CLASSIFICATIONS OF NERVOUS TISSUE FUNCTIONS SPECIAL MODALITIES ONLY APPLY TO THE HEAD AND NECK. GENERAL MODALITIES (NON-SPECIAL MODALITIES) WHETHER THE NERVE FIBERS ARE CARRYING SENSORY OR MOTOR INFORMATION. WHETHER OR NOT THE NERVE FIBERS ARE CARRYING SOMATIC OR VISCERAL INFORMATION. WE CAN CATEGORIZE GENERAL NERVOUS SYSTEM FIBERS BASED ON FOUR GENERAL FUNCTIONAL MODALITIES: GENERAL SOMATIC SENSORY: OUR SENSE OF TOUCH, PRESSURE, PAIN, TEMPERATURE, AND PROPRIOCEPTION GENERAL SOMATIC MOTOR: VOLUNTARY MOVEMENT BY SKELETAL MUSCLES GENERAL VISCERAL MOTOR: INVOLUNTARY MOVEMENT OF OUR CARDIAC AND SMOOTH MUSCLE AND SECRETION FROM GLANDS GENERAL VISCERAL SENSORY: MONITORING AND SENSING UNCONSCIOUS INFORMATION PRIMARILY COMING FROM OUR ORGANS AND GLANDS