Downloaded 51 times
More Related Content
Similar to Chapter 3 The Human Body
Chapter 3 The Human Body
- 1.
- 2. The Human Body •First aiders must be familiar with the basic structure and functions of the human body. • The most important and sensitive organs include: • Lungs • Heart • Brain • Spinal cord
- 3. The Respiratory System(1 of 2) • Death will result in about 4 to 6 minutes if the body’s oxygen supply is cut. • Oxygen from air is made available to the blood through the respiratory system.
- 4. The Respiratory System(2 of 2)
- 5. Respiration The Passage ofAir Into and Out of the Lungs • Mechanics of breathing: • Inhalation is breathing in. • Exhalation is breathing out. • Ventilation is a mechanical process that alternately increases and decreases the size of the chest cavity.
- 6. Respiratory Information Infants andChildren • Respiratory structures are smaller. • Easily obstructed airways • Tongues take up more space in the mouth. • Trachea is more flexible. • Primary cause of cardiac arrest is an uncorrected respiratory problem.
- 7. Respiratory Rates • Decreasesat rest • Increases during exercise • Controlled by the brain
- 8. Signs of InadequateBreathing • A rate outside the normal range • Cool or clammy skin that is pale or cyanotic • Nasal flaring
- 9. Respiration When Hard MuscularWork Is Performed • Lungs cannot get rid of carbon dioxide. • Lungs cannot take in oxygen fast enough at the normal rate. • As carbon dioxide increases, respiration increases. • Heart rate increases.
- 10. The Circulatory System(1 of 2) • Blood • Heart • Blood vessels
- 11. The Circulatory System(2 of 2) • Blood carries nutrients and other products from the digestive tract. • Blood carries oxygen from the lungs. • Blood transports wastes.
- 12. Heart (1 of4) • Pumps blood through the vessels • A powerful, hollow, muscular organ • About the size of a man’s clenched fist • Shaped like a pear • Located in the left center of the chest
- 13. Heart (2 of4) • Divided by a wall to create the right and left compartments • Compartments are divided into two chambers: • Atrium above • Ventricle below
- 14. Heart (3 of4) During each contraction: • The heart pumps blood high in carbon dioxide and low in oxygen from the right ventricle to the lungs. • Oxygen-rich blood is returned to the left atrium of the heart from the lungs.
- 15. Heart (4 of4) • Left ventricle pushes oxygen-rich blood to the rest of the body. • Right atrium receives oxygen-poor blood.
- 16. Blood Vessels (1of 4) • Arteries • Elastic, muscular tubes that carry blood away from the heart • Begin at the heart as two large tubes • Pulmonary artery: Carries blood to the lungs • Aorta: Carries blood to other parts of the body and divides into capillaries
- 17. Blood Vessels (2of 4) • Capillaries • A network of extremely fine vessels • Oxygen and nourishment pass out of the bloodstream into the body’s cells. • Cells discharge waste into the bloodstream. • In the lungs, carbon dioxide is released and oxygen is absorbed.
- 18. Blood Vessels (3of 4) • Veins • Become larger and larger • Form major trunks that empty blood returning from the body into the right atrium • Blood returning from the lungs goes into the left atrium.
- 19. Blood Vessels (4of 4)
- 20. Pulse • Surge ofblood that occurs each time the heart contracts • Can be felt at any point where an artery lies near the skin surface • Blood from a cut artery spurts. • Blood from a cut vein flows.
- 21. Locations for FeelingPulses • Carotid artery • Femoral artery • Radial artery • Brachial artery • Posterior tibial artery • Dorsalis pedis artery
- 22. Blood Pressure • Bloodpressure is a measure of the pressure exerted by the blood on the walls of the flexible arteries.
- 23. Blood • Liquid portion •Plasma • 90% water • Carries food materials • Carries waste materials • Solid portion • Red blood cells • Give blood its color • Carry oxygen • White blood cells • Defense against infection • Platelets • Essential for blood clot formation
- 24. Hypoperfusion (Shock) • Inadequatecirculation of blood through an organ • Signs and symptoms include: • Pale or cyanotic, cool, clammy skin • Rapid pulse • Rapid breathing • Restlessness, anxiety, or mental dullness • Nausea and vomiting • Reduction in total blood volume • Low or decreasing blood pressure • Subnormal body temperature
- 25. The Nervous System Thenervous system is a complex collection of nerve cells (neurons) that coordinate the work of all parts of the human body and keep the individual in touch with the outside world.
- 26. Neurons • Receive stimuli •Transmit impulses • Produce nerve impulses • Cannot be regenerated
- 27. Central Nervous System TheBrain (1 of 5) • Headquarters of the human nervous system • Most highly specialized organ • Requires considerable oxygen • Three main subdivisions • Cerebrum • Cerebellum • Brain stem
- 28. Central Nervous System TheBrain (2 of 5) • Cerebrum • Divided into two hemispheres • Controls functions such as sensation, thought, and associative memory • The occipital lobe is the sight center. • The temporal lobes direct smell and hearing.
- 29. Central Nervous System TheBrain (3 of 5) • Cerebellum • Located at the back of the cranium, skull, below the cerebrum • Coordinates muscular activity and balance
- 30. Central Nervous System TheBrain (4 of 5) • Brain stem • Extends from the base of the cerebrum to the foramen magnum • Controls breathing and heart rate
- 31. Central Nervous System TheBrain (5 of 5) • Cerebrospinal fluid • Similar to blood plasma • Circulates throughout the brain and spinal cord • Serves as a protective cushion • Exchanges food and waste materials
- 32. Central Nervous System SpinalCord (1 of 2) • Soft column of nerve tissue • Exits the brain through the foramen magnum • Thirty-one pairs of spinal nerves branch from the spinal cord
- 33. Central Nervous System SpinalCord (2 of 2) • Some fibers carry impulses in, others carry impulses away. • Spinal nerves at different levels regulate activities of various parts of the body. • Vulnerable to injury • Damage is usually irreversible. • Injury can cause paralysis.
- 34. Peripheral Nervous System •Made up of nerves that exit the spinal cord through an opening in the bony canal • Consists of the sensory and motor nerves • If a nerve is seriously damaged, the body part will not work.
- 35. Autonomic Nervous System Controls: •Heart rate • Digestion • Sweating • Other automatic body processes
- 36. The Skeletal System •Adult skeleton has 206 bones. • Bones are made of living cells surrounded by hard deposits of calcium.
- 37. Skull (1 of3) • Rests at the top of the spinal column • Houses the brain, certain glands, and the centers of special senses • Two parts • Brain case (cranium) • Face
- 38. Skull (2 of3) • Blood vessels and nerve trunks pass to and from the brain through openings in the skull. • Can be fractured • Does not “give” • The face extends from the eyebrows to the chin.
- 39.
- 40. Spinal Column (1of 2) • Consists of irregularly shaped bones called vertebrae • Lie on top of each other to form a strong, flexible column • Bound together by ligaments • Can be damaged by disease or injury
- 41. Spinal Column (2of 2) • Careless handling of an injured person can further injure the cord and possibly the person. • A person with a back or neck injury must be handled with extreme care.
- 42. Thorax • Also knownas the rib cage • Made up of ribs and the sternum • Injuries to the thorax can puncture the lungs and heart. • Lowest portion of the sternum is the xiphoid process.
- 43. Pelvis • Formed bytwo hipbones and the sacrum • Muscles help connect pelvic bones, trunk, thighs, and legs. • Forms the floor of the abdominal cavity • Holds the bladder, rectum, and internal parts of the reproductive organs
- 44. Leg Bones (1of 3) • Upper leg (thigh) • Femur • Knee • Knee joint • Patella
- 45. Leg Bones (2of 3) • Lower leg • Tibia • Fibula
- 46. Leg Bones (3of 3) • Ankles, feet, and toes
- 47. Shoulder • Shoulder girdle •Collarbone (clavicle) • Shoulder blade (scapula) • Fractures are common.
- 48. Arm Bones (1of 2) • Upper arm • Humerus • Easily dislocated • Forearm • Ulna • Radius
- 49. Arm Bones (2of 2) • Wrist, hand, and fingers • Composed of eight bones (carpals) • Tendons from forearm to fingers • The palm has five long bones (metacarpals). • Fourteen bones of the fingers (phalanges) • The thumb is the most important digit.
- 50. Joints • Where twoor more bones meet or join • Some allow little movement, others allow a wide range. • Layer of cartilage acts as a buffer. • Ligaments hold the bones and act as bands of flexible connective tissue. • Enclosed in a capsule • A thick fluid lubricates and protects the joint.
- 51. The Muscular System(1 of 2) • Voluntary muscles • Under control of the person • Make all deliberate acts possible • Called skeletal muscles • Can be injured in many ways
- 52. The Muscular System(2 of 2) • Smooth muscles • Very little control by the person • Line the walls of tubelike structures • Cardiac muscle • Found only in the heart • Needs continuous oxygen and glucose
- 53. The Skin (1of 2) • Covers entire body • Protects deep tissues from being injured, drying out, or being invaded by bacteria and other foreign bodies • Regulates body temperature
- 54. The Skin (2of 2) • Epidermis (outer layer) • Varies in thickness • Dead cells are constantly worn off. • Dermis (inner layer) • Rich supply of blood vessels and nerve endings • Contains sweat glands and oil glands • Above the subcutaneous layer