Presentation on theme: "NervousSystem Integumentary System Skeletal System Muscular System Circulatory System Respiratory System Digestive System Excretory System Endocrine System."— Presentation transcript:
NervousSystem Integumentary System Skeletal System Muscular System Circulatory System Respiratory System Digestive System Excretory System Endocrine System Reproductive System Lymphatic System
The Skeletal System 1.The Skeleton 2.Bone Structure 3.Bone Development 4.Joints
Skull Sternum Ribs Vertebral column Axial Skeleton - Supports the central axis of the body. Metatarsals Metacarpals Phalanges Clavicle Scapula Humerus Radius Pelvis Ulna Carpals Femur Patella Fibula Tibia Tarsals Phalanges Appendicular Skeleton - The bones of the appendages (arms, shoulder area, legs, and pelvis). The Human Skeleton The adult human skeleton has 206 bones and is divided into two parts:
Functions of the Skeleton Support – hold up the body Protection – rib cage, skull, and pelvic girdle protect important organs Movement – skeletal muscle attaches to the bones of the skeleton to allow movement Storage – bones store fat, calcium, minerals Hematopoeisis – blood cell formation
Bone Structure Bone - a solid network of living cells and fibers that are supported by deposits of calcium salts Periosteum – tough layer of fibrous connective tissue that surrounds bone Compact Bone – dense bone that makes up the bulk of the skeleton Haversian Canals – canals that run through compact bone that contain blood vessels and nerves Spongy Bone – porous bone found in the ends of long bones and in the middle of short and flat bones Bone Marrow – found in the cavities of bones
Bone Marrow red marrow is in spongy bone –production of blood cells yellow marrow is found in the central cavity of long bones –stores fat and acts as an energy reserve
Cartilage cushions the ends of bones –elbows, hips, and knees provides structure –nose and ears –much of a newborn's skeleton is made of cartilage
Bone Development Cartilage pre-cursor – cartilage is slowly replaced by bone through a process called ossification Osteoblasts – bone forming cells Osteoclasts – bone destroying cells Osteocytes – regulate cellular activities of bone Thought Question: What disease is caused by an imbalance between Osteoblast and Osteoclasts?
Joints Ball and Socket Joint (shoulder) - bones can rotate while moving back and forth and side to side Hinge Joint (knee) - allows movement back and forth in one plane Pivot Joint (top of neck and base of skull) - one bone rotates around another
Muscle Tendon Femur Patella Bursa Ligament Synovial fluid Cartilage Fat Fibula Tibia Tendon - connective tissue attaching muscle and bone. Ligament – connective tissue attaching bones Thought Question: Based on the diagram, what is the difference between a tendon and a ligament? The Knee
The Muscular System 1.Types of Muscle Tissue 2.Muscle Contraction
3 Types of Muscle Skeletal Cardiac Smooth
Smooth Muscle Found in internal tubes and vessels – digestive and circulatory systems Moves food, blood, and other substances through the body Involuntary - not under conscious control Not striated uninucleated
Cardiac Muscle The muscle of the heart Main function is to pump blood Striated Involuntary
Skeletal Muscle Attached to bones of the skeleton Allows for movement Striated – alternating light and dark bands Voluntary – under conscious control Multinucleated Also called muscle fibers Complete muscle tissue = muscle fibers, connective tissues, blood vessels, and nerves
Can you identify the type of muscle shown below?
Skeletal muscle Bundle of muscle fibers Actin Myosin Sarcomere Z disc Muscle fiber (cell) Myofibril Muscle cells are bundled together and are surrounded by a connective sheath. An individual muscle cell is a long fiber with many nuclei. Each muscle cell contains a central cable made of a rodlike structures called myofibrils Myofibrils are composed of two types of protein, actin and myosin. They make up the light and dark bands in functional units called sarcomeres. Structure of Skeletal Muscle
Relaxed Muscle Contracted Muscle Z disc MyosinActinZ disc Sarcomere Cross-bridgesZ disc Movement of Actin Filament Actin Binding sites Cross- bridge Myosin myosin - thick filaments, have many bump- like projections called "heads" actin - thin filaments, like a string of twisted beads, the ends of the actin strands are attached to Z lines 1. myosin heads attach to the actin filaments forming cross bridges 2. the heads of the myosin filaments walk along the actin filaments, pulling them toward the center of the sarcomere How a Muscle Contracts
Click on the link below to view a video showing a muscle contract: Thought Question: Based on the requirements necessary for muscle contraction, what organelle would you expect to find in high concentration in muscle cells?
Actin pulled Cross-bridge releases actin Cross-bridge changes shape Myosin returns to original shape Myosin forms cross-bridge with actin Muscle Contraction When a muscle contracts, the heads of the myosin filaments walk along the actin filaments, pulling them toward the center of the sarcomere. As this occurs simultaneously in sarcomeres throughout the cell the muscle cell contracts.
Essays 1.When a person decides to move, his skeletal muscles contract. Explain how a muscle contracts by discussing: a)What the contractile/functional unit of a muscle is called. b)What two proteins are involved in muscle contraction. c)Discuss the steps of skeletal muscle contraction (use the terms: Sarcomere, Actin, Myosin, Crossbridge, Z-Discs) 2.Explain how the human skeleton accomplishes the following functions: a) Allows movement, protects internal organs, store mineral reserves, and provide a site for blood cell formation. b.) Be sure to explain where in the bones these tasks occur. c.) Explain two diseases that disrupt homeostasis by preventing these functions.