Muscle Tissue 1
Muscle types and functional characteristicsLevels of organization and microanatomy of muscle
The basicsMuscles are attached to bonesMuscles contract (get shorter) and move bonesMuscles comprise 40-50% of body massMyology
Study of muscle anatomy and physiology
Myo- Mys- Sarco- = prefixes that reference muscle
Muscle functional characteristicsExcitable / excitability
ability to respond to stimuli
Contractile / -ilityability to shorten; initiated by nerve signal (action potential)
Extensible / -ilityability to stretch; lengthen
Elastic / -icityability to return to original length
Types of muscleSkeletal
Attached to bones, striated, voluntary
CardiacForms heart, striated, involuntary
SmoothWalls of blood vessels, stomach intestines, hair follicles, non-striated, involuntary
Muscle FunctionsMotion
contraction moves bones; bodyblood flowperistalsis (squeezing of intestines)gall and urinary bladder contraction
Posture maintenance / joint stabilization
Thermoregulationcontraction results in heat energy release
Skeletal muscle contraction(microanatomical TEM)
Skeletal muscle tissue organization
ConnectionsTendons
Dense connective tissue continuous with deep fascia, connect muscles to periosteum
AponeurosesBroad flat tendon attachment to bone, or to different muscle, or skin
Microanatomy
Muscle Contraction RequirementsNerve impulse
A nerve penetrates every muscleSynaptic bulb / neuromuscular junction = muscle connection with nerve cell
BloodSupplies energy, nutrients, oxygenRemoval of waste and heatEach muscle fiber is in contact with capillaries