Lesson 1 Flashcards
There are more or less ___ muscles in the human body
600
Study of the muscular system
Myology
an organ system that permits movement in the body, maintains posture and circulates blood throughout the body
Muscular System
Three types of muscles
Skeletal
Cardiac
Smooth
Properties of Muscles
Excitability/Irritability
Contractility
Extensibility
Elasticity
Tonicity
receive and respond to stimulus
Excitability/Irritability
to shorten and tighten
Contractility
stretch or extend upon the application of force
Extensibility
regain the original shape and size after being stretched
Elasticity
to steadily contract
Tonicity
Function of Muscles
M-H-A-P-P:
Movement
Heat Production
Alters diameters of tubes and vessels in the body
Posture
Protection of vital organs
How many % of body heat is derived from muscle contraction
85%
Two types of muscles according to the type of action:
Voluntary - can be made contract
Involuntary - can’t be controlled by the will
Muscle cells composition
-75% water for hydration
-20% CHON for repair and energy production
-5% Glycogen for ATP production
Voluntary and striated
40% of TBW
Ability to contract, cause and stop movement
Example: breathing and speech, making facial expression
Skeletal Muscles
With alternating ight and dark bands
Characteristics:
Striated
entire heart contracts as one unit
syncytium
Other term for cardiac muscle
Cardiocytes/Heart muscles
Cardiac muscles has the length of and diameter of:
Length: 50-100
Diameter: 10-20
Involuntary
Striated
Autorhythmic
Cardiac muscles
The heart beats ________ per day
100,000
contraction of muscle without apparent stimulation or without frank stimulation
Autorhythmicity
muscle fibers are multinucleated structures
Skeletal Muscles
fibers have one to two nuclei and are physically and electrically connected to each other
Cardiac Muscles
Involuntary
non-striated
fibers are small, spindled-shape, mononucleated with lesser actin and myosin
Smooth Muscle
ability of smooth muscle to stretch without developing a lasting high tension
Plasticity
layers of connective tissue that encloses muscle and provide structure to th muscle as a whole and also compartmentalize the muscle fibers within the muscle
Mysia
sheath of dense fibrous connective tissue beneath the skin or around muscle fibers, holds muscle fibers together
Connective Tissue Coverings/Fascia
connective tissue surrounding the skeletal muscle
Epimysium
connective tissue that surrounds muscle fasicles
Perimysium
connective tissue that surrounds single muscle fibers
Endomysium
bundle of fibers
Fascicles
muscle cells that composes a fasciculus
Muscle Fiber
Skeletal muscle attachments:
T-A-T:
Tendon
Aponeuroses
Tendon Sheaths
attaches muscle to the periosteum of a bone
Tendon
flat layer ghin of sheets that attach to the coverings of a bone, another bone, or the skin
Aponeuroses
tubes of fibeous connective tissue that encloses certain tendons especial at the wrist and ankle
Tendon Sheathes
Attachment of bone ends of skeletal muscles:
Origin
Insertion