Membranes, Muscle Tissue & Neural Tissue Chapter 4 (cont.)

I.Membranes- made of epithelial & connective tissues A.Mucous Membranes 1.Line the cavities that communicate w/ the exterior 2.Surfaces stay lubricated w/ mucous 3.Ex. digestive, respiratory, reproductive & urinary tracts

B.Serous Membranes 1.Line the sealed, internal divisions of the ventral body cavity 2.Thin, firmly attached to cavity wall & organ 3. Ex. pleura, peritoneum & pericardium

C.Cutaneous Membrane 1.Covers the surface of the body 2.Thick, relatively waterproof, dry 3.Ex. skin

D.Synovial Membrane 1.Line the synovial cavities of joints 2.Fxn in allowing significant movement in the joints

II. Connective Tissue Framework A.Provides strength & stability B.Maintains the relative positions of internal organs C.Provides a route for the distribution of blood vessels, lymph & nerves

D.Fasciae- C.T. layers & wrappings that support & surround organs 1.Superficial Fascia (subcutaneous layer/hypodermis) a.Areolar & adipose tissue that separates skin from underlying tissues & organs b.Provides insulation & padding c.Lets skin move independently from underlying structures

2.Deep Fascia a.Dense irregular C. T. b.Resistant from forces of different directions 3.Subserous Fascia a.Areolar tissue b.Separates serous membranes from deep fascia c.Protects serous membranes from movement of muscles

III. Muscle Tissue A.Specialized for contraction 1.Skeletal Muscle a.Contains very large muscle cells (up to 1 ft + in length!) b.Cells are called “muscle fibers” c.Cells are multinucleated d.Appear banded or “striated” e.Usually only contract if stimulated by nerves f.AKA striated, voluntary muscle

2.Cardiac Muscle a.Only located in the heart b.Cells are called cardiocytes c.Cells are branched d.Cells are smaller than skeletal muscle cells e.Cells do not rely on nerves to contract f.AKA striated involuntary muscle

3.Smooth Muscle a.Cells are small, spindle-shaped, w/ tapered ends b.Found: i.In the walls of blood vessels ii.Around hollow organs such as the bladder iii.In layers around the respiratory, digestive & reproductive tracts c.AKA nonstriated, involuntary muscle

IV. Neural Tissue (Nervous Tissue) A.Specialized for the conduction of electrical impulses from one region of the body to another B.98% of neural tissue is found in the brain & spinal cord

C.Cell Types 1.Neurons a.Communicate our thoughts b.Longest cell in the body (up to 1 meter!) c.Cannot divide or repair themselves

2.Neuralgia (Glial Cells) a.Provide supporting framework for neural tissues b.Help supply nutrients to neurons