Visual Anatomy & Physiology First Edition Martini & Ober Chapter 4 Muscle & Nervous Tissues Lecture 11

2 Mid-term Grades (based on 3 grades ) - Revised Based on the three (3) grades you have received so far, you should do a mid-term checkup to see how you’re doing. To find your average so far, total the three grades you’ve received and divide by 300 (the total amount of points possible so far for the courses). Ex: keeping all grades: ( )  300 = 0.74 (74%) Ex: dropping the low grade: ( )  200 = 0.86 (86%) To figure out what you need to AVERAGE on the next lecture and two lab exams plus the final COMBINED to get your desired grade for the course : Pts desired (from syllabus) - Total pts. so far 450 (if no grade dropped) or 550 (if low grade dropped) = Average grade needed on remaining exams

3 Points and Grades (from Syllabus) - Revised Grade for Course Grade as %Points (of a possible 800)Quality Points A A B B B C C D D Example 1: To get a grade of B for the course, using the example grades on previous slide, and not dropping lowest grade (50), and assuming 50 pts for lab and 4 XC points: 656 – ( ) = x; x = 0.84 (84%) Average on upcoming exams 450 Example 2: To get a grade of B for the course, using the example grades on previous slide, and dropping lowest grade (50), and assuming 50 pts for lab and 4 XC points: 656 – ( ) = x; x = 0.78 (78%) Average on upcoming exams 550

4 Lecture Overview Connective tissue framework of the body Introduction to muscle tissue Classification/characteristics of muscle tissue Overview of nervous tissue Inflammation and repair

5 CT Framework of the Body Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001 Fascia connects the organs of the dorsal and ventral cavities with the rest of the body Provide: - Strength - Stability - Organ position - Conduits

6 Fascia and CT of Skeletal Muscle Figure from: Hole’s Human A&P, 12 th edition, 2010

7 CT and the Heart Figure from: Hole’s Human A&P, 12 th edition, 2010

8 Muscle – Overview General characteristics –Elongated cells with special properties –Muscle cells (myocytes) = muscle fibers –Contractile (major property of all muscle) –Use actin (thin) and myosin (thick) for contraction Three types of muscle tissue –Cardiac –Skeletal –Smooth

9 Skeletal Muscle Skeletal muscle attached to bones striated voluntary multinucleated unbranched Like most other highly differentiated cells, skeletal muscle is incapable of cell division, but new fibers can be formed by other cells

10 Skeletal Muscle Fibers Nuclei lie just internal to the cell membrane Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001 Satellite cells = progenitor cells

11 Skeletal Muscle Cells (Fibers) Figure from: Alberts et al., Essential Cell Biology, Garland Press, 1998 A skeletal muscle cell (muscle fiber) Lengths can be up to the entire length of a muscle (30 cm or 12 in)!

12 Skeletal Muscle Contraction Figure from: Hole’s Human A&P, 12 th edition, 2010

13 Smooth Muscle Smooth muscle walls of organs and blood vessels skin involuntary not striated (it’s smooth!) single, centrally located nucleus unbranched Smooth muscle cells normally don’t divide but they can if there is a need to regenerate tissue Figure from: Hole’s Human A&P, 12 th edition, 2010

14 Smooth Muscle Relaxed (superficial view) Contracted (superficial view) Figures from: Martini, Anatomy & Physiology, Prentice Hall, 2001 Notice that the contractile filaments within the cells are organized very differently than skeletal muscle – no sarcomeres = no striations

15 Cardiac Muscle Cardiac muscle heart wall (myocardium) involuntary (& autorhythmic) striated intercalated discs branched single nucleus (usually) Cardiac muscle cells may also be called cardiocytes or cardiac myocytes or myocardial cells Figure from: Hole’s Human A&P, 12 th edition, 2010

16 Cardiac Muscle Tissue Important points: - Almost totally dependent upon aerobic metabolism - Intercalated disks consist of gap junctions and desmosomes - Myofibrils are oriented longitudinally (like skeletal muscle) Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001 Regenerative capability is limited; no satellite cells

17 Nervous Tissue found in brain, spinal cord, and peripheral nerves conduction of nerve impulses basic cells are neurons sensory reception neuroglial cells are supporting cells Figure from: Hole’s Human A&P, 12 th edition, 2010

18 Nervous Tissue Figures from: Martini, Anatomy & Physiology, Prentice Hall, 2001 Neuroglia - Maintain physical structure - Repair framework after injury - Perform phagocytosis - Provide nutrients to neurons

19 Introduction to Inflammation Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001 Restoration of homeostasis after tissue injury or infections involves two processes: 1) inflammation and 2) repair. Hallmarks of inflammation: Redness, heat, pain, swelling, and loss of function (Inflammation = ‘-itis’)

20 Inflammatory Response From: mh/loosct2l.jpg From: Saladin, Human Anatomy & Physiology, McGraw Hill, 2007

21 Eicosanoid Synthesis and Inflammation From: From: Saladin, Human Anatomy & Physiology, McGraw Hill, 2007 (COX)

22 Review The connective tissues (CT) create the internal framework of the body –Layers of CT connect the organs with the dorsal and ventral cavities –Fasciae (singular, fascia) CT layers and wrappings that support and surround organs Superficial fascia Deep fascia Subserous fascia

23 Review NAME OF MUSCLE TISSUE DESCRIPTION OF STRUCTURE TYPE OF CONTROL LOCATIONFUNCTION SKELETAL MUSCLE long, thin fibers with many nuclei and striations Voluntaryattached to bonesto move bones SMOOTH MUSCLE spindle shaped cells with one centrally located nucleus, lacking striations Involuntarywalls of visceral hollow organs, irises of eyes, walls of blood vessels to move substances through passageways (i.e. food, urine, semen), constrict blood vessels, etc CARDIAC MUSCLE a network of striated cells with one centrally located nucleus attached by intercalated discs Involuntaryheartpump blood to lungs and body

24 Review The restoration of homeostasis following injury or infection involves two steps: –Inflammation Isolates injured/infected tissue Activates mast cells (histamine, heparin) Attraction of immune/phagocytic cells to clean up –Repair Fibroblasts move in to stabilize injury site (scar tissue) Different tissues have different ability to repair injury –Epithelia and CT regenerate very well –Smooth/skeletal muscle regenerate poorly –Cardiac muscle and nerve cannot regenerate at all