Organization of the Human Body An Introduction to Human Anatomy and Physiology Leonardo da Vinci’s Vitruvian Man Leonardo da Vinci’s Vitruvian Man expresses the correlation of man’s body proportions. For example, man’s outstretched arms are equivalent to his height. What else does da Vinci prove within his Vitruvian Man sketch? * Extra credit on the first test. Key Terms Anatomy – The science of structure and the relationships among structures Physiology – The science of body functions and how the body parts work. You can’t have one without the other. Function can never be separated completely from structure. Example: The bones of the skull are tightly joined to form a rigid structure (anatomy) The function of the rigid structure is to protect the delicate brain within (physiology) Levels of Organization Atoms ( C, H, N, O, P, S ) Molecules ( DNA & RNA ) Cell ( muscle, nerve and blood ) Tissue ( connective, muscle and nervous ) Organ ( heart, liver, brain ) Organ System ( digestive system ) Organism ( human ) The 6 Life Processes Metabolism Responsiveness Movement Growth Differentiation Reproduction Survival Needs • Nutrients Slide 1.17a • Chemicals for energy and cell building • Includes carbohydrates, proteins, lipids, vitamins, and minerals • Oxygen • Required for chemical reactions Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Survival Needs • Water • 60–80% of body weight • Provides for metabolic reaction • Stable body temperature • Atmospheric pressure must be appropriate Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 1.17b Homeostasis • Maintenance of a stable internal environment = a dynamic state of equilibrium Slide 1.18 • Homeostasis must be maintained for normal body functioning and to sustain life • Homeostatic imbalance – a disturbance in homeostasis resulting in disease Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Maintaining Homeostasis • The body communicates through neural and hormonal control systems Slide 1.19a • Receptor • Responds to changes in the environment (stimuli) • Sends information to control center Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Maintaining Homeostasis • Control center • Determines set point Slide 1.19b • Analyzes information • Determines appropriate response • Effector • Provides a means for response to the stimulus Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Feedback Mechanisms • Negative feedback Slide 1.20a • Includes most homeostatic control mechanisms • Shuts off the original stimulus, or reduces its intensity • Works like a household thermostat Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Feedback Mechanisms Positive Feedback – Increases the original stimulus to push the variable farther – In the body this occurs only in blood clotting and child birth The Language of Anatomy • Special terminology is used to prevent misunderstanding • Exact terms are used for: • Position • Direction • Regions • Structures Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 1.21 Anatomical Position I Anatomical Position II Planes of the Human Body Orientation and Directional Terms Table 1.1 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 1.22 Orientation and Directional Terms Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Table 1.1 (cont) Slide 1.23 Directional Terms Directional terms precisely locate various parts of the body in relation to one another. Not shown are superficial (surface) and deep ( interior ) Directional Terms II The hand is distal to the shoulder. The lungs are lateral to the heart. The heart is Superior to the bladder. The ribs are Deep to the skin. Body Systems The human body is composed of 11 body systems The Integumentary System Consists of the skin and the structures derived from it. Includes hair, nails, sweat and oil glands. Regulates body temp. Protects body Dectects sensations The Skeletal System Consists of the bones, cartilage and joints. Supports and protects the body. Assists with movement. Stores cells that produce blood cells. Stores minerals and fats. The Muscular System Consists of skeletal muscle, but also includes cardiac and smooth muscle. Aides in movement. Maintains posture. Produces heat. Digestive System Physically and chemically breaks down food. Absorbs nutrients and eliminates wastes. Consists of mouth, esophagus, stomach, small and large intestines, rectum and anus. Also includes salivary glands, liver, pancreas and gallbladder. Nervous System Consists of brain, spinal cord, nerves and sense organs such as the eyes and ears. Regulates body activities through nerve impulses. Responds to changes via muscular contractions or glandular secretions. The Cardiovascular System Consists of the heart, blood and blood vessels. Heart pumps blood through blood vessels. Blood carries O2 and nutrients to the cells. Regulates body temp. Blood components help to fight disease and mend damaged vessels. The Respiratory System Consists of lungs, larynx, pharynx, trachea and bronchial tubes. Transfers oxygen from inhaled air to blood and carbon dioxide from blood to exhaled air. Regulates acidity of body fluids. Aides in sound production. The Endocrine System Consists of all of the glands and tissues that produce chemical regulators of body functions through hormones to various target organs. The Reproductive System Female ~ Consists of the ovaries, uterus, uterine tubes, vagina and mammary glands. Makes oocytes Male ~ Consists of the testes, epididymis, vas deferens and penis. Makes sperm Urinary System Consists of the kidneys, ureters, urinary bladder and urethra. It functions to produce, store and eliminate urine. Regulates volume and chemical make up of blood. Regulates red blood cell production. Lymphatic and Immune System Consists of the lymph, spleen, tonsils, lymphatic fluid, thymus and immune cells. Returns proteins and fluid to blood. Aides in protection against disease causing organisms. Proportions of the Human Body The average adult is 7 and a half heads tall and 3 heads wide from shoulder to shoulder. Hips are halfway from your head to toes and arms out to the side equals your height. Arms and hands at the side fall halfway between the hips and knees.