Muscle & Nervous Tissue OBJECTIVES: 1.Differentiate between the 3 types of muscle tissue. 2.Be able to identify muscle tissues by sight. 3.Anatomy of a neuron 4.Different method of tissue repair

Muscle Tissue  Highly specialized to contract/shorten to produce movement.  3 Types: Skeletal Cardiac Smooth

1. Skeletal Muscle  Attached to the skeleton  Can be controlled voluntarily  Causes gross body movements  Cells of muscle tissue are long, cylindrical, have many nuclei, and are striated (striped).

2. Cardiac Muscle  Found only in the heart.  Is striated  Cells fit tight together at junctions called intercalated disks. Intercalated disks contain gap junctions that allow impulses to travel.  Involuntary control.

3. Smooth Muscle  No visible striations.  Cells have a single nucleus and are spindle shaped.  Found in walls of hollow organs (stomach, bladder, uterus)  Can contract (making organ smaller) or enlarge (making organ dilate) to move substances along.  Peristalsis: moving food through the esophagus.

Nervous Tissue  Found in the brain, spinal cord, & nerves  Specialized to react to stimuli and conduct impulses.  Made up of cells called neurons.

Tissue Repair  Tissues repair themselves in 2 major ways. Regeneration: the replacement of destroyed tissue by the same kind of cells. Fibrosis: involves repair by dense connective tissue forming scar tissue.  The type of repair chosen depends on the type of tissue damaged and the severity of the injury.  Clean cuts heal much more easily and quickly than rips or tears.