Post on 03-Jan-2016
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Muscle Tissue
• Muscle cells/fibers– Elongated – Contain many myofilaments: Actin & Myosin
• FUNCTION– Movement– Maintenance of posture– Joint Stabilization– Heat Generation
• Three types: Skeletal, Cardiac, Smooth
Skeletal Muscle Tissue(each skeletal muscle is an organ)
• Cells– Long and cylindrical, in bundles– Multinucleate– Obvious Striations
• Skeletal Muscles-Voluntary• Connective Tissue Components:
– Endomysium-surrounds fibers– Perimysium-surrounds bundles– Epimysium-surrounds the muscle
• Attached to bones, fascia, skin• Origin & Insertion
academic.kellogg.cc.mi.us/.../muscular.htm
Cardiac Muscle
• Cells– Branching, chains of cells– Single or Binucleated– Striations– Connected by Intercalated discs
• Cardiac Muscle-Involuntary• Myocardium-heart muscle
– Pumps blood through vessels
• Connective Tissue Component– Endomysium: surrounding cells www.answers.co
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Smooth Muscle Tissue
CellsSingle cells, uninucleateNo striations
Smooth Muscle-Involuntary2 layers-opposite orientation (peristalsis)
Found in hollow organs, blood vesselsConnective Tissue Component
Endomysium: surrounds cells
Nervous Tissue
• Neurons: specialized nerve cells conduct impulses– Cell body, dendrite, axon
• Characterized by:– No mitosis (cell replication)– Longevity– High metabolic rate
www.morphonix.com
Nervous Tissue: control
• Support cells (= Neuroglial): nourishment, insulation, protection– Satellite cells-surround cell bodies within ganglia– Schwann cells-surround axons (PNS)– Microglia-phagocytes– Oligodendrocytes-produce myelin sheaths around
axons– Ependymal cells-line brain/spinal cord, ciliated, help
circulate CSF
• Brain, spinal cord, nerves
Aponeuroses of abdominal muscles
21. External Obliques
22. Rectus Abdominus
23. Sheath of the straight muscle of the abdomen
31. Sartorius
32. Rectus Femoris
33. Pectineus
35. Adductor Longus
Psoas Major
Musculoskeletal System
• Skeleton – Muscles function by pulling against bones that rotate about joints
and transmit force through the skin to the environment.– The skeleton can be divided into the axial skeleton and the
appendicular skeleton.
• Skeletal Musculature – A system of muscles enables the skeleton to move. – Origin = proximal (toward the center of the body) attachment– Insertion = distal (away from the center of the body) attach-ment
• Cardiocytes occur only in the heart
• Striated involuntary muscle
• Relies on pacemaker cells for regular contraction
Cardiac muscle
• Neurons– Transmit information
• Neuroglia– Support neural tissue– Help supply nutrients to neurons
Neural tissue cells
• Injured tissues respond in coordinated fashion
• Homeostasis restored by inflammation and regeneration
Tissue Injuries and AgingInflammation and regeneration
• Isolates injured area
• Damaged cells, tissue components and dangerous microorganisms removed– Infection avoided
• Regeneration restores normal function
Tissue Injuries and AgingInflammatory response
• Change with age
• Repair and maintenance less efficient
• Structure altered
• Chemical composition altered
Aging and tissue repair
Aging and cancer incidence
• Incidence of cancer increases with age
• 70-80% of all cases due to exposure to chemicals or environmental factors
You should now be familiar with:• The four major tissue types and their
functions.
• The relationship between form and function for each tissue type.
• The types and functions of epithelial tissues.
• The structure and function of connective tissues.
• The structure and function of the four types of membrane.
• The three types of muscle tissue and the structural features of each.
• The basic structure and role of neural tissue.