Basic Physiology Flashcards
Muscle Tissue
Made up of contractile fibers that are under neural control
3 types of muscle
Smooth
Cardiac
Striated
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 system
Can be partially contracted for long periods of time
Cells 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 it
INVOLUNTARY
Cells are branched
Striated
AKA skeletal or VOLUNTARY muscle
usually attached to the skeleton and can move parts of it
43% of adult body weight is composed of skeletal muscles
Each fiber is made up of longitudinally arranged MYOFIBRILS
Fibers are not branched, but packaged in parallel bundles
Skin is made up of 2 layers
Epidermis and Dermis
Epidermis
Squamous and stratified in organization
Tissue is not vascularized
Functions of the skeletal system
1) Support - provide rigid framework for body
2) Mechanical basis of movement- providing attachments for muscles, levers for them to act on
3) Protection - rigid walls or cages that house vital organs
4) Source of blood cells: RBCs, lymphoctes, WBCs, platelets
5) Storage of salts - mineral resevoir for calcium, phosphorus, and magnesium
Types of Bones
Compact (Cortical)
Cancellous
Bone Marrow
Compact (cortical) bone
Dense outer shell around cancellous bone
Harder stronger stiffer than cancellous bone
Supports weight of the body, made up of calcium and minerals
Primary anatomical and functional unit is called an osteon
Cancellous (trabecular/spongy) bone
Consists of slender, irregular bars (trabeculae) of compact bone forming a matrix
Highly vascular
Interconnecting spaces are filled with bone marrow, production of blood cells occurs
Primary functional unit of cancellous bone is trabecula
Bone Marrow
Red bone marrow is active blood formation
Yellow bone marrow which is mainly inert and fatty
Classification by Shape (5)
1) Long
2) Short
3) Flat
4) Irregular
5) Sesamoid
Long Bones
Designed for leverage and weight bearing
Greater in length than width, can be curved
Tubular, consisting of a shaft (diaphysis) and two ends (epiphysis)
Ends form articulations and are covered with hyaline cartilage
Example: Femur
Short bones
Cuboidal in shape
Only found in wrist and hand
Six surfaces : four or less for articulation, rest for attachment of tendons and ligaments or entry of blood vessels
Example: Carpals
Flat Bones
Designed for protection and muscle attachment
Consists of two plates of cortical bone with spongy bone and marrow between
Examples: vertebrae, some of the facial bones
Irregular Bones
Complex design and shape
Have some or all of characteristics of long, short, flat bones
Examples: Vertebrae
Sesamoid Bones
Round or oval nodules of bone that develop in tendons that pass over certain articulations
Articular side is covered in cartilage, other side is buried in the tendon
function is to protect tendon from wear and improve mechanical advantage of tendon acting on a joint
Examples: Patella, Pisiform, and Sesamoids of 1st ray in LE
Classification of Bone by Region
Axial
Appendicular
Axial Skeleton
Includes the skull vertebrae, ribs, and sternum
Appendicular
Bones associated with and including the upper and lower limbs
Classification of Joints
Fibrous
Cartilaginous
Synovial
Fibrous Joint
Little or no movement
No joint cavity
Articulating bones are bound tightly with fibrous connective tissue
Examples: Suture joint between cranial bones, tibiofibular joint
Exception: interosseus membrane uniting the radius and ulna, which allows pronation/supination
Cartilaginous Joint
Little or no movement
No joint cavity
Articulating bones bound tightly with cartilage
Example: Sacro-coccygeal
