Three classes of muscle Skeletal muscle - responsible for locomotion Cardiac muscle - responsible...
-
Upload
calvin-miller -
Category
Documents
-
view
217 -
download
0
Transcript of Three classes of muscle Skeletal muscle - responsible for locomotion Cardiac muscle - responsible...
Three classes of muscle
• Skeletal muscle - responsible for locomotion
• Cardiac muscle - responsible for the action of the heart
• Smooth muscle - responsible for the contraction of irregular shaped organs such as the intestines.
MUSCLE TISSUE
Skeletal muscle100 µm
Multiple nuclei
Muscle fiber
Sarcomere
Cardiac muscle
Nucleus Intercalateddisk
50 µm
Smooth muscle Nucleus
Musclefibers
25 µm
NERVOUS TISSUE
NeuronsProcess
Cell body
Nucleus
50 µm
Structure and Function of Skeletal Muscle
Skeletal Muscle
• Mammal body contains over 400 skeletal muscles
– Approx. 40-50% of total body weight
Skeletal Muscle
• Functions of skeletal muscle
– Force production for locomotion and breathing
– Force production for postural support
– Heat production during cold stress
– Saleable product in livestock production
Skeletal Muscles
• Muscles generally work in pairs to produce movement
• One muscle flexes (or contracts) the other relaxes
• This process is known as antagonism
Structure of Skeletal Muscle:Connective Tissue Covering
• Epimysium– Surrounds entire muscle
• Perimysium– Surrounds bundles of muscle fibers
• Fascicles
• Endomysium– Surrounds individual muscle fibers
Structure of Skeletal Muscle:Microstructure
• Sarcolemma– Muscle cell membrane
• Myofibrils– Threadlike strands within muscle fibers– Actin (thin filament)
• Troponin• Tropomyosin
– Myosin (thick filament)
CollagenousfiberElasticfiber
Chondrocytes
Chondroitinsulfate
Loose connective tissue
Fibrous connective tissue
100
µm
100 µm
Nuclei
30 µm
Bone Blood
Centralcanal
Osteon
700 µm 55 µm
Red blood cellsWhite blood cell
Plasma
Cartilage
Adipose tissue
Fat droplets
150
µm
CONNECTIVE TISSUE
Smooth MusclesLumen ofstomach
Mucosa. The mucosa is anepithelial layer that linesthe lumen.
Submucosa. The submucosa isa matrix of connective tissuethat contains blood vesselsand nerves.
Muscularis. The muscularis consistsmainly of smooth muscle tissue.
0.2 mm
Serosa. External to the muscularis is the serosa,a thin layer of connective and epithelial tissue.
Smooth muscle