1. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Muscle Tissue  Function is to produce movement  Three types  Skeletal muscle  Cardiac muscle  Smooth muscle

2. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings

3. Skeletal muscle  voluntarily controlled  Contracts to pull bones/skin  Produces gross body movements or facial expressions  Characteristics of skeletal muscle cells  Striated  Multinucleate (more than one nucleus)  Long, cylindrical

4. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings SKELETAL MUSCLE Figure 3.20a

5. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings CARDIAC MUSCLE  involuntarily controlled  Only in the heart  Function=pump blood  Characteristics  Cells attached to other cardiac muscle cells at intercalated disks  Striated  One nucleus per cell

6. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings CARDIAC MUSCLE Figure 3.20b

7. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings SMOOTH MUSCLE  Involuntary  Found in walls of hollow organs such as stomach, uterus, and blood vessels  Characteristics  No visible striations  One nucleus per cell  Spindle-shaped cells

8. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Muscle Tissue Types Figure 3.20c

9. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Nervous Tissue Figure 3.21

10. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Nervous Tissue  Includes neurons (nerve cells)  Converts stimuli to nerve impulses  Fxn=irritability & conductivity  Has a unique structures

11. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Neuron(Nerve Cells): highly specialized nerve cell that transmits messages Cell Body: the metabolic center of the neuron Dendrites: convey incoming messages(electrical signals); highly branched; may be hundreds of branches Axons: generate nerve impulses & conduct them away from the cell body; only one axon per neuron

12. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Tissue Repair (Wound Healing)  Regeneration  Replacement of destroyed tissue by the same kind of cells  Fibrosis  Repair by dense (fibrous) connective tissue (scar tissue)  Determination of method  Type of tissue damaged  Severity of the injury

13. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Events in Tissue Repair  Capillaries become very permeable  Introduce clotting proteins  A clot walls off the injured area  Formation of granulation tissue  Growth of new capillaries  Rebuild collagen fibers  Regeneration of surface epithelium  Scab detaches

14. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Regeneration of Tissues  Tissues that regenerate easily  Epithelial tissue (skin and mucous membranes)  Fibrous connective tissues and bone  Tissues that regenerate poorly  Skeletal muscle  Tissues that are replaced largely with scar tissue  Cardiac muscle  Nervous tissue within the brain and spinal cord

15. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Developmental Aspects of Tissue  Epithelial tissue arises from all three primary germ layers  Muscle and connective tissue arise from the mesoderm  Nervous tissue arises from the ectoderm  With old age, there is a decrease in mass and viability in most tissues