BasicPhysiology Flashcards
Muscle Tissue
Made up of contractile fibers that are under neural control
3 types of muscle
SmoothCardiacStriated
Smooth
Usually formed in sheets surrounding hollow viscera- digestive tract- respiratory tract- blood vessels, uterine walls etc.INVOLUNTARY as it is innervated by the autonomic nervous systemCan be partially contracted for long periods of timeCells interlocked and regional contraction occurs instead of single fiber contractions
Cardiac
Only found in walls of the heart and base of the great vessels adjacent to itINVOLUNTARYCells are branched
Striated
AKA skeletal or VOLUNTARY muscleusually attached to the skeleton and can move parts of it43% of adult body weight is composed of skeletal musclesEach fiber is made up of longitudinally arranged MYOFIBRILSFibers are not branched, but packaged in parallel bundles
Skin is made up of 2 layers
Epidermis and Dermis
Epidermis
Squamous and stratified in organizationTissue is not vascularized
Functions of the skeletal system
1) Support - provide rigid framework for body2) Mechanical basis of movement- providing attachments for muscles, levers for them to act on3) Protection - rigid walls or cages that house vital organs4) Source of blood cells: RBCs, lymphoctes, WBCs, platelets5) Storage of salts - mineral resevoir for calcium, phosphorus, and magnesium
Types of Bones
Compact (Cortical)CancellousBone Marrow
Compact (cortical) bone
Dense outer shell around cancellous boneHarder stronger stiffer than cancellous boneSupports weight of the body, made up of calcium and mineralsPrimary anatomical and functional unit is called an osteon
Cancellous (trabecular/spongy) bone
Consists of slender, irregular bars (trabeculae) of compact bone forming a matrixHighly vascularInterconnecting spaces are filled with bone marrow, production of blood cells occursPrimary functional unit of cancellous bone is trabecula
Bone Marrow
Red bone marrow is active blood formationYellow bone marrow which is mainly inert and fatty
Classification by Shape (5)
1) Long2) Short3) Flat4) Irregular5) Sesamoid
Long Bones
Designed for leverage and weight bearingGreater in length than width, can be curvedTubular, consisting of a shaft (diaphysis) and two ends (epiphysis)Ends form articulations and are covered with hyaline cartilageExample: Femur
Short bones
Cuboidal in shapeOnly found in wrist and handSix surfaces : four or less for articulation, rest for attachment of tendons and ligaments or entry of blood vesselsExample: Carpals