NERVOUS SYSTEM PART 1

WE LEARNED A LOT OF THINGS THIS WEEK ESPECIALLY ABOUT THE BASIC INFORMATION ABOUT OUR BRAIN AND SPINAL CORD. THAT THEY ARE THE MAIN DIVISIONS OF OUR NERVOUS SYSTEM. OUR NERVOUS SYSTEM IS DIVIDED INTO 2 PARTS THE CNS (CENTRAL NERVOUS SYSTEM) AND PNS (PERIPHERAL NERVOUS SYSTEM). OUR CNS IS COMPOSED OF THE BRAIN AND THE THE BRAIN STEM WHILE OUR PNS IS COMPOSED OF THE SPINAL CORD AND THE SPINAL NERVES. WHICH IS MAINLY TACKLED IN THIS WEEK. FOR EXAMPLE THE SO CALLED DEEP GROOVE IS THE VENTRAL MEDIAN FISSURE AND THE SHALLOW GROOVE IS THE DORSAL MEDIAN SULCUS. THE AREA WHERE THE NERVES HAS THEIR CELL BODIES IS THE GRAY MATTER HORNS.

INTEGUMENTARY SYSTEM

INTEGUMENTARY SYSTEMIS COMPOSED OF NAILS, HAIR AND THE SKIN. INTEGUMENTARY SYSTEM PROTECTS US FROM PATHOGEN INVASION, HELPS KEEP THE BODY FROM DRYING OUT, ACTS AS STORAGE FOR FATTY TISSUE, PRODUCES VIT. D, PROVIDES SENSORY INPUT, AND IT REGULATES BODY TEMPERATURE. SKIN IS COMPOSED OF 3 LAYERS THE EPIDERMIS, THE DERMIS AND THE SUBCUTANEOUS FASCIA. NAILS ARE SPECIALIZED CELL ORIGINATING FROM THE NAIL ROOTS. HAIR HELPS REGULATE BODY TEMPERATURE. IT IS COMPOSED OF KERATIN. SHAFT IS THE HAIR THAT YOU SEE. SEBUM IS SECRETED BY THE SEBACEOUS GLANDS THAT IS OILY AND SOMEWHAT ANTIBACTERIAL

MUSCULAR SYSTEM

MUSCULAR SYSTEM IS MAINLY COMPOSED OF MUSCLES. MUSCLES ARE ALL CONTRACTILE TISSUES, THAT IS APPROXIMATELY THE DIAMETER OF A HAIR. IT CAME FROM THE LATIN WORD "MUS" WHICH MEANS MOUSE SINCE IT MOVES LIKE A MOUSE UNDER OUR SKIN. IT HAS 3 TYPES THE SKELETAL, THE SMOOTH AND THE CARDIAC MUSCLES. SKELETAL MUSCLES ARE VOLUNTARY MUSCLES THAT IS ATTACHED TO THE BONES. IT IS ALSO CALLED STRIATED MUSCLES AND IT PROVIDES MOVEMENT FOR THE BODY. SMOOTH MUSCLES ARE THE ONE FOUND IN OUR ORGANS THEY ARE INVOLUNTARY. CARDIAC LIKE SMOOTH MUSCLE IS INVOLUNTARY AND IT IS FOUND IN OUR HEART. THE PRIMARY MOVERS ARE THE AGONISTS WHILE THE MUSCLE CAUSING MOVEMENT TO OPPOSITE DIRECTION IS THE ANTAGONISTS. THE MUSCLE END ATTACHED TO THE STATIONARY BONE IS THE POINT OF ORIGIN AND THE MUSCLE THAT IS ATTACHED TO THE MOVING BONE IS CALLED THE POINT OF INSERTION. THE ONE WHO ASSISSTS IN MOVEMENT IS THE SYNERGISTIC. ROTATION IS THE CIRCULAR MOVEMENT OCCURING AROUND AN AXIS. ABDUCTION IS THE MOVEMENT AWAY FROM THE MIDLINE OF THEBODY IS ABDUCTION AND THE OPPOSITE OF IT IS ADDUCTION.

SKELETAL SYSTEM II

I LEARNED ALL ABOUT JOINTS. JOINTS ARE THE PLACE WHERE THE BONES MEET; JOINTS ARE ALSO CALLED ARTICULATION. THIS IS HELD TOGETHER BY A LIGAMENT. JOINTS HAVE 3 TYPES ACCORDING TO FUNCTION THESE ARE IMMOBILE, CAN MOVE A LITTLE AND FREELY. JOINTS IS ALSO CLASSIFIED ACCORDING TO STRUCTURE THESE ARE FIBROUS, CARTILAGINOUS AND SYNOVIAL. SYNOVIAL JOINTS ARE CLASSIFIED INTO 7 THE SADDLE, CONDYLOID, ELLIPSOIDAL, PIVOT, BALL & SOCKET, HINGE, AND GLIDING. SADDLE JOINT'S MOVEMENT IS UP&DOWN AND SIDE2SIDE. CONDYLOID'S MOVEMENT IS FROM OTHER PLACE TO ANOTHER BUT NO ROTATION. ELLIPSOIDAL HAS 2 AXES OF MOVEMENT. PIVOT ROTATES, BALL & SOCKET CAN DO ALL. HINGE ARE OPEN AND CLOSE. GLIDING ARE BACK AND FORTH. I ALSO LEARNED ABOUT CARTILAGE. THE SPECIAL CONNECTIVE TISSUE THAT CAN WITHSTAND FAIR AMOUNT OF FLEXION.

SKELETAL SYSTEM

SKELETAL SYSTEM HAS MANY FUNCTIONS IT INCLUDES FRAMEWORK, IT PRODUCES RED BLOOD CELLS, PROTECTS VITAL ORGANS SUCH AS BRAIN, PROVIDES MOVEMENT. WE ARE COMPOSED OF 206 BONES. THEY ARE CLASSIFIED INTO LONG, SHORT, FLAT AND IRREGULAR BONES. IT IS CONNECTED BY A LIGAMENT. WHEN BONES MEET OTHER BONE THEY FORM JOINTS OR ARTICULATION.BONES HAVE TWO TYPES NAMELY SPONGY AND COMPACT.

TISSUES

TISSUES ARE GROUP OF CELLS THAT HAS FUNCTION. WHEN TISSUES GROUP TOGETHER THEY FORM ORGANS. THERE ARE 4 TYPES OF TISSUE THE EPITHELIAL, CONNECTIVE, MUSCLE AND THE NERVOUS TISSUES. CONNECTIVE TISSUES ARE FIBROUS TISSUES, CONNECTIVE TISSUES ARE TENDONS AND LIGAMENTS, MUSCLE TISSUE PROVIDE MEANS FOR MOVEMENT AND NERVOUS TISSUES ARE INSTANT MESSENGERS OF THE BRAIN. THE STUDY TISSUE IS CALLED HISTOLOGY.