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HUMAN MOVEMENT SYSTEM. Skeletal and muscular system. Concept mapping. What is skeleton?. Skeleton: collection of bones that holds our body up. Baby has 305 bones and an adult has 206 bones Why ? because as we grown some of our bones join together to form one bone. Types of skeletons.
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What is skeleton? • Skeleton: collection of bones that holds our body up. • Baby has 305 bones and an adult has 206 bones • Why ? • because as we grown some of our bones join together to form one bone
Types of skeletons • Exo-skeleton: animals that have shells • Endo-skeleton: hard structure inside the animal. • Hydrostatic skeleton: • Fluid held inside the body • No skeleton
Five functions of our skeletons • Protect the vital organs 2. Give us shape 3. Allow us to move because our muscles are attached to our bones 4. Storage of nutrients such as calcium and silicon 5. Formation of blood cells
Cranium Human skeletons Clavicle Mandible Scapula Sternum Rib Humerus Vertebra Innominate Radius Sacrum Ulna Carpals Meta carpals Falangs Femur Patella Tibia Fibula Metatarsals Tarsals
Components of Skeletal System Bone Cartilage: three types Hyaline Fibro cartilage Elastic 6-9
Bone Shapes • Long / Pipe • Ex. Upper and lower limbs • Short • Ex. Carpals and tarsals, bones in wrist and ankles • Flat • Ex. Ribs, sternum, skull, scapulae • Irregular • Ex. Vertebrae, facial
Long Bone Structure • Long bone surrounds by tissues called periosteum • Under periosteum is tissues called compact bone/ hard bone which contains bone cells, blood vessels, Ca, Phosphorus, and elastic fibers • Ends of long bone covered by tissues called cartilage
What is bone marrow? • Fatty tissue, located in the cavities in the center of long bones or spaces of spongy bones • Red marrow produce erythrocytes, most of leucocytes and platelets • Yellow marrow produce some leucocytes. It colors is due to the much higher number of fat cells
Flat, Short, Irregular Bones • No diaphyses and not elongated
Central or Haversian canals: parallel to long axis • Perforatingor Volkmann’s canal: perpendicular to long axis. Both perforating and central canals contain blood vessels. Direct flow of nutrients from vessels through cell processes of osteoblasts and from one cell to the next. • Lamellae: concentric, circumferential, interstitial • OsteonorHaversian system: central canal, contents, associated concentric lamellae and osteocytes • Osteocytes. Mature bone cells. Surrounded by matrix • Lacunae: spaces occupied by osteocyte cell body • Canaliculi: canals occupied by osteocyte cell processes
Bone Histology • Bone matrix. Like reinforced concrete. Rebar is collagen fibers, cement is hydroxyapetite • Organic: collagen and proteoglycans • Inorganic: hydroxyapetite. CaPO4 crystals • Bone cells (see following slides for particulars) • Osteoblasts Formation of bone through ossification or osteogenesis. • Osteocytes • Osteoclasts Resorption of bone • Stem cells or osteochondral progenitor cells • Woven bone: collagen fibers randomly oriented • Lamellar bone: mature bone in sheets • Cancellous bone: trabeculae • Compact bone: dense
Bone Matrix • If mineral removed, bone is too bendable • If collagen removed, bone is too brittle • Extracellular matrix contains mineralization by crystal which contains Ca, Phosphate, and Carbonate (Hydroxyapetite)
Cancellous (Spongy) Bone • Trabeculae: interconnecting rods or plates of bone. Like scaffolding. • Spaces filled with marrow. • Covered with endosteum. • Oriented along stress lines
Bone Development cartilages (before born) Osteoblast (bone forming cells contains Ca and P) Osteocytes (bone cells) Osteoclast (destroy bone tissues and release Ca and P in blood circulation)
Chicken Bone Experiment Aim To see what happens to bones when we leave them in acid (vinegar) and water. This experiment can be set up and left in your classroom for the next four days after which the students will see the results. Students mission is to write up what they think will happen to the chicken bones in each bottle and why? Materials and Equipment Clean chicken bones ( thigh bones) Two glass jars with lids per group Water White vinegar Paper towels
PROCEDURE • Place some chicken bones in each jar. • Label one jar with your groups name, date and ‘water’ – add the bones and water • Label the second jar with your groups name, date and ‘vinegar’ – add bones and vinegar • Leave the jars for about 3 weeks after which you can remove and dry the bones on some paper towels • Observe the difference in the two sets of bones • DISCUSSION • What has happened to each set of bones and why?
Factors Affecting Bone Growth Size and shape of a bone determined genetically but can be modified and influenced by nutrition and hormones Nutrition Lack of calcium, protein and other nutrients during growth and development can cause bones to be small Vitamin D Necessary for absorption of calcium from intestines Can be eaten or manufactured in the body Rickets: lack of vitamin D during childhood Osteomalacia: lack of vitamin D during adulthood leading to softening of bones Vitamin C Necessary for collagen synthesis by osteoblasts Scurvy: deficiency of vitamin C Lack of vitamin C also causes wounds not to heal, teeth to fall out 6-23
Factors Affecting Bone Growth, cont. Hormones Growth hormone from anterior pituitary. Stimulates interstitial cartilage growth and appositional bone growth Thyroid hormone required for growth of all tissues Sex hormones such as estrogen and testosterone Cause growth at puberty, but also cause closure of the epiphyseal plates and the cessation of growth 6-24
Bone Fractures • Open (compound)- bone break with open wound. Bone may be sticking out of wound. • Closed (simple)- Skin not perforated. • Incomplete- doesn’t extend across the bone. Complete- does • Comminuted fractures: complete with break into more than two pieces 6-25
Joints • Joints are the point were bones meet. There are two groups, movable and immovable joints • Ball-and-socket joints- formed when a rounded head of one bone fits into the rounded cavity of an jointed bone. • Hinge joints-would include elbow, knee, ankle, and fingers. Allows extension and retraction of apendage • Sadle joints- A saddle joint allows movement back and forth and up and down, bot does not allow for rotation like a ball and socket joint.
Gliding joints- In a gliding or plane joint bones slide past each other. Midcarpal and midtarsal joints are gliding joints. • Pivot joints- allow limited rotation or turning of the head • Ellipsoidal joints- bone in wrist, and a oval shaped part that fits in a curved space, the joints slide over each other
Muscles An organ that can contract to become shorter Functions of the Muscular System Involuntary Some involuntary functions of the muscular system are muscles to help you breathe, make your heart beat, and help move food through the digestive system. Voluntary Some voluntary functions of the muscular system are like playing piano, running, playing video games, and throwing a ball.
Muscles An organ that can contract to become shorter
Cardiac Muscle • One, centrally located nucleus • Presence of striations • Short, branched cells • “involuntary” • Myogenic (contraction originates within the muscle cell) • Does not fatigue
Skeletal Muscle • Many, peripherally located nuclei (develops from many myoblasts) • Presence of striations • Long (up to 30 cm), thin cells • “voluntary” • Neurogenic (contraction is initiated my motor neuron input) • Can fatigue
Smooth Muscle • One, centrally located nucleus • No striations • Short, tapered cells • “involuntary” • Myogenic with some neurogenic modulation • Does not fatigue
Muscle Roles in Specific Movements • Synergists = muscles that work together to produce certain movements (ex. Multiple arm muscles are needed for flexion of the antibrachium) • Antagonists = muscle(s) that work(s) to oppose certain actions = moves the structure in the opposite direction (ex. Triceps brachii is an antagonist to the biceps brachii and causes extension of the antibrachium)
Gross Anatomy of Muscles • Muscles consist of a – • Belly= the region with the muscle fibers • Tendon= connective tissue at the ends of the muscle that is continuous with the muscle and the connective tissue layer of the bone to which the muscle attaches • Fascia = connective tissue layer that surrounds the muscle
Injuries to Joints and Bones Fractures Joints Dislocation- is when the ligaments attached to the bone are torn or out of place Torn cartilage- is a sharp blow or twisting of the joint Arthritis- inflammation of the joint and is a result of natural wear and tear
Fasiculus = a bundle of muscle fibers, many per muscle Epimysium (fascia) = connective tissue layer that holds many fasiculi together, with the associated nerves, arteries and veins, to form a muscle (an organ) Muscle Fiber = a single muscle cell Perimysium = connective tissue layer that surrounds and produces a fasiculus Endomysium = connective layer surrounding a single muscle fiber
Microscopic anatomy of muscle cells Sarcomere = smallest contractile unit in a muscle fiber; extends from Z-line to Z-line A (anisotrophic band) band = “without change band” = at low magnification it looks the same regardless of the contractile state of the muscle; contains thick myofilaments overlapped with thin myofilaments I (isotrophic band) band = “with change band” = density changes at low magnification depending upon the contractile state of the muscle; at rest, contains only thin myofilaments Z-lines = dense regions at the ends of sarcomeres, serve as sites of thin filament attachment H-zone = region in the middle of the A-zone that at rest contains only thick filaments
Muscular Contraction • Impulse from nervous system
Sliding Filament Theory of Muscular Contraction Muscle contraction occurs when thick (myosin) and thin (actin) myofilaments are allowed to interact; thin filaments “slide” along thick filaments to the center of the sarcomere, thus shortening the contractile unit
Some Muscles 1. Gastrocnemius 2. Sartorius 3. Deltoid 4. Sternocleidomastoid 5. Tibialis 6. Hamstring group 7. Rectus Abdominus 8. Triceps 9. Biceps 10. Extensor Group