The Muscular System

1. The Muscular System By: Olivia DaCosta, Jeremy Boutin & Nick Lachapelle Bio Med Honors: Period 4

2. Muscle Cells (Myocytes) • Muscle cells are called Myocytes and form after the fussing of Myoblast cells, which are simple cells that originate as a type of undifferentiated stem cell. • The nucleus of the Myocytes branch off into Myofibers that are composed of long chains of bands called Sarcomere made of fibrous proteins, Myosin and Actin. • Both of these proteins can bind to each other when exposed to calcium and detach when exposed to sodium, allowing the entire muscle to contract and relax when exposed to synapses. • Cardiac Myocytes are also responsible for generating electric impulses pertaining to heart rates.

4. Types of Muscle Tissue/Organs

5. Smooth Muscle Tissue/Organs: • These muscles are used for involuntary functions of the body’s internal system such as breathing, digestion and sexual arousal. • Smooth muscles are involuntary due to the fact that they are controlled by the Autonomic Nervous System that controls subconscious factors.

6. Cardiac Muscle Tissue/Organs • Composed of Cardiomyocytes that also are striated muscles that are controlled involuntary. • These cells are used in order to pump blood throughout the body from the heart through planned contractions. This allows oxygen and nutrients to be transported throughout the body while waste is removed. • These muscles also allow electric pulses to be passed through the heart rate and synapses from the nervous system.

7. Skeletal Muscle Tissue/Organs • Skeletal muscles are also highly dense muscles that are composed of long cylindrical fibers that are created by the tightly packed muscle cells. • These muscles are also bound by connective tissue, such as the ones binding them to bone, endomysium (connecting muscle fibers), perimysium (Binds Fibers into groups) and Epimysium (Binds all groups of fibers together, closing off the muscle). Background: Muscle Tissue under microscope. IMAGE ON NEXT SLIDE 

9. The Main Organs

10. The Heart • The heart is an organ that supplies blood and oxygen to all parts of the body. It is the size of a clenched fist, and weights about 10.5 ounces. • The heart is located in the chest cavity, posterior to the the breast bone, between the lungs and superior to the diaphragm. • It is surrounded by a fluid filled sac called the pericardium.

11. The Tongue • The tongue is a muscular hydrostat on the floors of the mouths of most vertebrae's which manipulates food for mastication. • It is the primary organ of taste (gestation), the upper surface of the tongue is covered in papillae and taste buds. • It is richly supplied with nerves and blood vessels. • The tongue also serves as a natural means of cleaning ones teeth.

12. The biceps • The biceps brachii, is a two headed muscle. The biceps lie on the upper arm between the shoulder and the elbow. • Both heads arise on the scapula and join to form a single muscle belly, and that is attached to the upper forearm. • The main function of the biceps is at the latter where it flexes the elbow. • ->Example: Used when opening a bottle with a corkscrew.

13. The Triceps • The triceps brachii is Latin for “three headed arm muscle.” • It is a large muscle on the back of the upper limb of many vertebrae’s. • This muscle is responsible for extension of the elbow joint. (When you straighten your arm.

14. Gluteus Maximus • Largest and most superficial of all three gluteal muscles it makes up a large portion of the shape and appearance of the buttocks. • It is a thick fleshy mass of a quadrilateral shape, and it forms the prominence of the nates.

15. Deltoids • A thick flat triangular muscle, that is responsible for the round shape of the shoulder. • One end is attached to the collar bone and shoulder blade, while the other one is attached to the humerus bone in the arm. • The deltoids take part in all of the movements of the upper arm, but their main action is to abduct the shoulder, lifting the arm sideways from the midline of the body. It also rotates the arm. • Deltoids are active during rhythmic swinging movements of the arm during walking, and during the propulsive phase of the front crawl.

16. Diseases that may affect the Muscular system

17. Central Core Disease • Presents as muscle weakness ranging from minimal to severe that requires assisted ventilation. • Symptoms of severe early onset central core disease include spinal deformities, hip dislocation, and joint contractures. • Diagnostic procedures include a muscle biopsy.

18. Chronic Fatigue Syndrome • CFS symptoms include, a generalized feeling of fatigue that lingers regardless of the amount of rest. • Muscle aches, pain and muscle weakness must last for at least 6 months for a diagnosis of this disease.

19. Compartment syndrome • Compartment syndrome occurs from pressure within the muscles. Severe injuries or athletic-type exertion causes swelling or bleeding within the muscle area. • Since the connective tissue, or fascia, does not stretch, increased pressure causes an interruption in the blood flow to the muscles. Intervention includes rapid pressure release to avoid permanent damage to the muscle.

20. Dermatomyositis • An inflammatory myopathy, presents as inflammation and a rash. • Symptoms include difficulty swallowing, muscle weakness and pain. It most commonly affects children 5 to 15 years of age and adults ages 40 to 60. • A similar condition, polymyositis, presents with weakness due to the breakdown of the muscles either suddenly or over several weeks.

21. Influenza • Symptoms: Muscle aches, when accompanied by other symptoms such as fever, runny nose, chills, fatigue, nausea, headache and loss of appetite, can be an indicator of a flu virus.

22. Isaac’s Syndrome • The National Institute of Neurological Disorders and Stroke states that Isaac's syndrome is a neuromuscular disorder with symptoms such as progressive muscle stiffness, twitching, delayed muscle relaxation, muscle pain and cramping. • When the affected muscles include the pharynx and larynx, expect difficulties with speech and breathing.

23. Lyme Disease • The first sign of infection by the Lyme disease bacterium in 70 to 80 percent of infected persons is a rash called erythemamigrans. • Other symptoms include muscle and joint aches. If left untreated, muscle tone loss leading to Bell's palsy may occur.

24. Muscular Dystrophy • Caused by flaws in muscle protein genes, affects people of all ages. • The Muscular Dystrophy Association states that types of muscular dystrophy include Duchenne, limb-girdle, myotonic, congenital, facioscapulohumeral, Emery-Dreifuss, distal, Becker and oculopharyngeal. • Diagnostic criteria to determine the type of muscular dystrophy include identifying the specific muscles involved and when the weakness first appeared.

25. Main Function of the muscular system: • Locomotion or mobility, strength, heat production, shock absorption, shaping the body, maintaining posture, and respiration. • In addition it plays a role in the digestive process by peristalsis to move the food through. It is also essential for pumping blood and plays a role in smooth muscles of the blood vessels to raise blood pressure during the stress response. • Muscles help the body to have mobility through the environment, and motility inside the body for its processes.

26. References • http://www.livestrong.com/article/88576-diseases-affect-muscular-system/ • http://www.uoguelph.ca/zoology/devobio/210labs/muscle1.html • http://www.bem.fi/book/02/02.htm • http://virtual.yosemite.cc.ca.us/rdroual/Course%20Materials/Elementary%20Anatomy%20and%20Physiology%2050/Lecture%20outlines/skeletal_muscle_physiology.htm