Transcript ppt_ch17e
17 Locomotion in humans • 17.1 Why do animals need a skeleton? • 17.2 The human skeleton • 17.3 General plan and functions of the human skeleton • 17.4 Joints • 17.5 Muscles • 17.6 Locomotion in humans • Mind Map 17.1 Why do animals need a skeleton? 17.1 Why do animals need a skeleton? 1 Support body weight 2 Help movement 17.1 Why do animals need a skeleton? Bones inside the body 17.2 The human skeleton 17.2 The human skeleton Human skeleton Bones Cartilage 17.2 The human skeleton Bones Composition 1 Living cells makes the bone hard 2 Minerals mainly calcium phosphate 17.2 The human skeleton spongy bone cartilage yellow bone marrow Bones compact bone 17.2 The human skeleton spongy bone contains red bone marrow produces blood cells small cavities 17.2 The human skeleton yellow bone marrow stores fat (in adults) 17.2 The human skeleton compact bone very hard & dense 17.2 The human skeleton On the two ends of bone Cartilage much softer and more flexible than bone does not contain calcium salts 17.2 The human skeleton Pressure Functions It is cushion-like acts as shock-absorber 17.2 The human skeleton Functions During movement reduces friction avoids wearing of bones 17.2 The human skeleton Functions can be found in ear pinna & the end of nose gives shape can be found in trachea keeps trachea open all the time 17.2 The human skeleton Cartilage Functions 1 Absorbs shock 2 3 Reduces friction Maintains shape 17.3 General plan and functions of the human skeleton 17.3 General plan and functions of the human skeleton Human skeleton skull sternum rib cage rib vertebral column collar bone pectoral girdle scapula humerus forelimb radius ulna pelvic girdle femur knee cap tibia fibula Axial skeleton hind limb Appendicular skeleton 17.3 General plan and functions of the human skeleton Skull cranium eye socket nose bones upper jaw teeth lower jaw 17.3 General plan and functions of the human skeleton Skull cranium eye socket nose bones upper jaw teeth immovable lower jaw movable 17.3 General plan and functions of the human skeleton Skull Function protects brain eyes ears 17.3 General plan and functions of the human skeleton Vertebral column spinal cord vertebra intervertebral disc 17.3 General plan and functions of the human skeleton Vertebral column S-shaped composed of 33 vertebrae Functions 1 protects spinal cord 2 gives support to upper part of the body 17.3 General plan and functions of the human skeleton Rib Cage Vertebral Column Sternum Rib 17.3 General plan and functions of the human skeleton Rib Cage 1 protects Functions lungs heart 2 involved in breathing 3 produces blood cells 17.3 General plan and functions of the human skeleton Appendicular skeleton pectoral girdle links arm with vertebral column 17.3 General plan and functions of the human skeleton Appendicular skeleton pelvic girdle links protects the organs in the lower part of the abdomen leg with vertebral column 17.3 General plan and functions of the human skeleton Human skeleton Functions weight 1 Support & maintenance of the body shape support 17.3 General plan and functions of the human skeleton Human skeleton Functions bends 2 extends For attachment of muscles and for movement 17.3 General plan and functions of the human skeleton Human skeleton Functions 3 rib heart lung Protection of internal organs 17.3 General plan and functions of the human skeleton Human skeleton Functions red bone marrow red blood cell 4 Production of blood cells white blood cell 17.3 General plan and functions of the human skeleton Human skeleton Functions compact bone tissue stores calcium salts and phosphorus 5 Storage yellow bone marrow stores fat 17.4 Joints 17.4 Joints Joints -- where two or more bones meet some are immobile e.g. sutures in the cranium some are mobile, called movable joints e.g. knee joint, elbow joint 17.4 Joints Structure ligaments bone 1 hold two bones together elastic tough bone 2 prevent dislocation allow movement 17.4 Joints Structure tendon articular cartilage muscle femur synovial fluid synovial membrane ligament tibia 17.4 Joints Structure synovial membrane secretes synovial fluid Reduce Friction 17.4 Joints Structure articular cartilage 1 Absorb shocks 2 Reduce friction 3 Prevent wearing 17.4 Joints Types of Joint Hinge joint Allows movement in ONE plane only 17.4 Joints Types of Joint Ball-andsocket joint Allows movement in ALL planes ball socket 17.4 Joints Ball-and-socket joint Hinge joint 1. Shoulder joint 1. Elbow joint 2. Hip joint 2. Knee joint 17.5 Muscles 17.5 Muscles Muscle contractio n force Energy (ATP) Respiration 17.5 Muscles Muscles attached to bone Skeletal muscles contracts powerfully for a long period of time 1 becomes shortened 2 becomes fatigued because of accumulation of lactic acid 17.6 Locomotion in humans 17.6 Locomotion in humans Muscle and the skeleton joining muscle to bones tendons made up of collagen bone muscle tough and inelastic transmit force from muscles to bones immediately 17.6 Locomotion in humans Comparisons between tendons and ligaments Tendon attaches muscle to bone Ligament attaches bone to bone elastic inelastic transmits force from muscles to bones prevents dislocatio n allows movement 17.6 Locomotion in humans Movement of the forearm biceps biceps contracts (thicker & shorter) triceps triceps relaxes (thinner & longer) Bending the arm 17.6 Locomotion in humans Movement of the forearm biceps biceps relaxes (thinner & longer) triceps contracts (thicker & shorter) triceps Straightening the arm 17.6 Locomotion in humans Movement of the forearm Bending the arm Straightening the arm biceps relaxes biceps contracts triceps relaxes Biceps Triceps triceps contracts Work in pair & carry out opposite actions Antagonistic (opposing) muscles 17.6 Locomotion in humans Movement of the forearm Bending the arm Straightening the arm biceps relaxes biceps contracts triceps relaxes triceps contracts Biceps bends a limb by contraction Flexor Triceps straightens a limb by contraction Extensor 17.6 Locomotion in humans Bone as levers muscles act on the bones across the joints bones are moved like levers 17.6 Locomotion in humans Bone as levers The force is transmitted along the lever to the load contraction of biceps (effort) hand (load) effort elbow joint (fulcrum) load fulcrum 17.6 Locomotion in humans Experiment 17.1 Examination of an arm model wooden board X nail string tying the balloon to a nail balloon B balloon A wooden board Z wooden board Y screw allowing movement of wooden board Z 17.6 Locomotion in humans Experiment 17.1 Examination of an arm model 1. Study the arm model. 2. Move wooden board Z so that it forms an angle of less than 90º with wooden board Y. Notice the thickness of the two balloons. 3. Move wooden board Z so that it forms a large angle with wooden board Y. (Wooden boards Y and Z may lie on the same line. The angle should not exceed 180 º.) Notice the thickness of the two balloons. 17.6 Locomotion in humans Experiment 17.1 Examination of an arm model Question 1: What parts of the forelimb are represented by the wooden boards and the screw between wooden boards Y and Z respectively? Answer: The wooden boards represent the bones and the screw between wooden boards Y and Z represents the elbow joint. 17.6 Locomotion in humans Experiment 17.1 Examination of an arm model Question 2: Which balloon represents the triceps? Which represents the biceps? Answer: Balloon A represents the triceps and balloon B represents the biceps. 17.6 Locomotion in humans Experiment 17.1 Examination of an arm model Question 3: What happens to the biceps and triceps as the forearm is bent or straightened? Answer: As the forearm is bent, the biceps contracts and becomes shorter and thicker, and the triceps relaxes and becomes longer and thinner. The actions of the two muscles oppose each other. To straighten the forearm, the biceps relaxes and the triceps contracts. Mind Map Locomotion in humans involves the coordination of skeleton is made up of linked up by held together by ligaments examples can be divided tendons into 1. bones joints skeletal muscles consists of 2. cartilage axial skeleton consists of 1. skull 2. vertebral column 3. ribs and sternum appendicular skeleton consists of 1. pectoral girdles 2. pelvic girdles 3. limb bones flexor example biceps extensor 1. hinge joints example triceps 2. ball-and -socket joints examples examples 1. knee joints 1. shoulder joints 2. elbow joints 2. hip joints