Chapter_1_The_human_body_an_orientation copy.pdf

Human Anatomy and Physiology-I Course code 1102 114 Dr. Fatemeh Saheb Sharif-Askari Reading materials Pages 1 – 23 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy...

Human Anatomy and Physiology-I Course code 1102 114 Dr. Fatemeh Saheb Sharif-Askari Reading materials Pages 1 – 23 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 2 Outlines of Chapter 1 1- An Overview of Anatomy and Physiology 2- Levels of Structural Organization 3- Maintaining Life 4- Homeostasis 5- The Language of Anatomy Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 3 12th Edition. Pearson. An Overview of Anatomy and Physiology Learning Objectives Define anatomy and physiology. Explain how anatomy and physiology are related. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 4 12th Edition. Pearson. Anatomy --- Definition Anatomy is the study of structure and shape of the body and its parts (organs [example; lungs], tissues, and cells) and their relationships to one another. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 5 12th Edition. Pearson. Anatomy: Subdivisions Anatomy has two subdivisions: 1- Gross anatomy = the study of large body structures that can be seen with the naked eye. 2- Microscopic anatomy = the study of small body structures (the cells and tissues) that can only be seen through a microscope. Gross anatomy of the lung Microscopic Anatomy of the lung Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 6 12th Edition. Pearson. Physiology: Definition & Subdivisions Physiology is the study of how the body and its parts work or function. Subdivisions: For example; Cardiac physiology (Function of the heart), Neurophysiology (workings of the nervous system) Example. Cardiac Physiology of the Heart Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 7 12th Edition. Pearson. An Overview of Anatomy and Physiology Learning Objectives Define anatomy and physiology. Explain how anatomy and physiology are related. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 8 12th Edition. Pearson.  Relationship between Anatomy and Physiology ▪ Anatomy and Physiology are always related. ▪Structure and function are complementary. Function reflects structure and structure determines function. Examples. The lungs are not muscular chambers like the heart and cannot pump blood through the body, but because the walls of their alveolus are very thin, they can exchange gases and provide oxygen to the body. 9 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. Outlines of Chapter 1 1- An Overview of Anatomy and Physiology 2- Levels of Structural Organization 3- Maintaining Life 4- Homeostasis 5- The Language of Anatomy Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 10 12th Edition. Pearson. Levels of Structural Organization Learning Objectives Name the 6 levels of structural organization that make up the human body, and explain how they are related. Name the 11 organ systems of the body, and briefly state the major functions of each system. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 11 12th Edition. Pearson. The human body exhibits 6 levels of structural complexity (example; Water, sugar, Protein) Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 12 Levels of Structural Organization Learning Objectives Name the 6 levels of structural organization that make up the human body, and explain how they are related. Name the 11 organ systems of the body, and briefly state the major functions of each system. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 13 12th Edition. Pearson. The human body is made up of 11 organ systems 14 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  The Integumentary System The Integumentary System is the external covering of the body, or the skin, including the hair and fingernails. ----Function It cushions and protects deeper tissues from injury. Excretes salts in perspiration and helps regulate body temperature. Sensory receptors located in the skin detect mechanical, thermal, or nociceptive (painful) stimuli applied on the body surface. When skin is exposed to sun light, it produces Vitamin D. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 15 12th Edition. Pearson.  The skeletal system The Skeletal System consists of bones, cartilages, and joints. ----Function ▪ Protects and supports body organs ▪ Provides a framework that the skeletal muscles use to cause movement. ▪ Site for blood cells formation. ▪ Stores essential minerals (like calcium) Blood cells formation in red bone marrow Skeletal muscle attached to bone 16 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  The Muscular System The Muscular System includes skeletal muscles, smooth muscle, and cardiac muscle. 1- Skeletal muscles, the large muscles attached to bones Function to contract (shorten) which cause body movements 2- Smooth muscles, the muscles of hollow organs Stomach Function to move fluids (such as blood or urine) or other substances (such as food) bladder Wall of intestine 3- Cardiac muscle, the muscle of heart Blood vessel Function to contract the heart and pump the blood Heart 17 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  The Nervous System The body’s fast-acting control system It consist of brain, spinal cord, nerves, and sensory receptors. ----Function: (1) It uses sensory receptors to monitor changes both occurring inside (decreases in oxygen) and outside (such as light, sound, and change in temperature) the body. The gathered information is called sensory input. (2) It processes and interprets the sensory input and decides what should be done at each moment—a process called integration. (3) It then trough motor output causes a response by activating muscles or glands (effectors) 18 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  The Endocrine System ▪ It is collection of glands, e.g., pituitary, thyroid, parathyroids, adrenals, thymus, pancreas, pineal, ovaries (in the female) and testes(in the male) ----Function: ▪ Endocrine glands produce hormones (chemical substances) and release them in blood to travel and change activities of target organs. ▪ Growth, reproduction, and the use of nutrients by cells are controlled by hormones. Disorders of pituitary growth hormone. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 19 12th Edition. Pearson.  The Cardiovascular System ▪ It consists of the heart and blood vessels ----Function ▪ The heart pumps blood into blood vessels. ▪ Blood vessels deliver blood rich in oxygen, nutrients, hormones, and other substances to cells and pick up wastes such as carbon dioxide from cells. ▪ In blood; white blood cells and chemicals help to protect the body from bacteria, viruses, and tumor cells. White blood cells (T-cells) attacking cancer cell Marieb, E.N. and Keller, S.M., 2020. Cardiovascular system Essentials of Human Anatomy & Physiology, 20 12th Edition. Pearson.  The Lymphatic system It includes, lymph nodes, lymphatic vessels & lymphoid organs (tonsils, thymus, spleen, Peyer’s patches, and appendix. lymphoid organs Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 21 12th Edition. Pearson.  The Lymphatic system ---Function: The lymphatic vessels When fluid is leaked into tissues from the blood vessels; lymphatic vessels return it to the bloodstream so that there is enough blood to continuously circulate through the body. The lymphatic nodes and lymphoid organs They cleanse the blood and are a place for white blood cells that are involved in immunity. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 22 12th Edition. Pearson.  The Respiratory System It includes nasal passages, pharynx, larynx, trachea, bronchi, and lungs. ----Function It keeps blood constantly supplied with oxygen and removes carbon dioxide Within the lungs are tiny air sacs. Gases are exchanged with the blood through the thin walls of these air sacs. 23 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  The Digestive System It is basically a tube running through the body from mouth to anus It includes oral cavity, esophagus, stomach, small and large intestines, rectum plus a number of accessory organs (salivary glands, liver, pancreas, etc.) Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 24 12th Edition. Pearson.  The Digestive System --Function: Breaks down food and deliver the resulting nutrients to the blood for distribution to body cells. Stomach produces enzymes and acids to break down food so Liver produces bile to helps it can pass small to break down fats intestine Small intestine helps to further break down food coming from the stomach. Pancreas delivers It absorbs nutrients (vitamins, minerals, carbohydrates, enzymes to the fats, proteins) and water from food so they can be used by small intestine to the body. break down food Large intestine reabsorb excess water from materials it receive from the small intestine The undigested food that remains in the tract leaves the body through the anus as feces. 25 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  Name an organ that has both endocrine and digestive function? pancreas Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 26 12th Edition. Pearson.  The Urinary System It includes the kidneys, ureters, bladder, urethra) --Function: Removes the nitrogen-containing wastes (examples are urea and uric acid) from the blood and eliminates them from the body in urine. It maintains the body’s water and salt (electrolyte) balance Regulates the acid-base balance of the blood Helps to regulate normal blood pressure 27 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  The Reproductive System Overall function of the reproductive system is production of offspring Female Ovaries produce eggs and female sex hormones Male Testes produce sperm and male sex Other structures serve as sites for fertilization hormone (fallopian tube) and development of the fetus (uterus). Ducts and glands aid in delivery of viable sperm to the female reproductive tract. Mammary glands of female breasts produce milk to nourish the newborn. ductus deferens 28 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  Organ Systems Inter-Relationships ▪ Organ systems do not work in isolation. ▪ They work together to promote the well-being of the entire body. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 29 12th Edition. Pearson. Outlines of Chapter 1 1- An Overview of Anatomy and Physiology 2- Levels of Structural Organization 3- Maintaining Life 4- Homeostasis 5- The Language of Anatomy Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 30 12th Edition. Pearson. Learning Objectives Maintaining Life List 8 functions that humans must perform to maintain life List the 5 survival needs of the human body Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 31 12th Edition. Pearson.  Necessary Life Functions There are 8 functions that humans must perform to maintain life: 1 - Maintaining boundaries 2 - Movement 3 - Responsiveness to environmental changes 4 - Digestion 5 - Metabolism 6 - Excretion 7 - Reproduction 8 - Growth Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 32 12th Edition. Pearson.  Maintaining boundaries Every living organism must be able to maintain its boundaries so that its “inside” (internal environment) remains distinct from its “outside” (external environment). Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 33 12th Edition. Pearson.  Maintaining boundaries The body as a whole is enclosed by the Every cell of the human body is surrounded integumentary system (skin). by an external membrane celled semipermeable plasma membrane. It protects internal organs from drying out due to effects of heat and sunlight and from The membrane separates contents of inside entry of pathogens (such as bacteria) and from the outside interstitial fluid (fluid chemical substances. between cells). Selective entry of needed substances while generally preventing entry of damaging substances. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 34 12th Edition. Pearson.  Movement Movement supported by skeletal muscles Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 35 12th Edition. Pearson.  Movement Movement supported by smooth muscles Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 36 12th Edition. Pearson.  Responsiveness Responsiveness, or irritability, is the ability of our body to sense changes (stimuli) in the internal or external environment and then to react to them (also called excitability). 2 2 1 1 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 37 12th Edition. Pearson.  Responsiveness The nervous system takes the major role for responsiveness - Because nerve cells are highly responsive and can communicate rapidly with each other via electrical impulses. However, all body cells are responsive to some extent. The boby nervous system Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 38 12th Edition. Pearson.  Digestion Digestion is the process of breaking-down ingested food into simple molecules that can then be absorbed into the blood. The nutrient-rich blood is then distributed to all body cells by the cardiovascular system, where body cells use these nutrients. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 39 12th Edition. Pearson.  Metabolism A broad term that refers to all chemical reactions that occur within body cells. ▪ It includes: Breaking down complex substances into simpler building blocks (breakdown of glucose) Making larger structures from smaller ones (synthesis of glucagon) Using nutrients and oxygen to produce molecules of Adenosine TriPhosphate (ATP) (the energy-rich molecules that power cellular activities). Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 40  Metabolism ▪ Metabolism depends on the digestive system to make nutrients and on respiratory system to make oxygen available to the blood and on the cardiovascular system to distribute these needed substances throughout the body. Metabolism is regulated chiefly by hormones secreted by the glands of the endocrine system. 41 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson.  Excretion ▪ Excretion is the process of removing wastes (excreta) from the body. ▪ Several organ systems participate in excretion. The skin excretes different types of The urinary system waste products in sweat The digestive system excretes nitrogen-containing excretes undigested food metabolic wastes in feces (stool) in urine Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 42 12th Edition. Pearson.  Reproduction It can occur on the cellular or organismal level. Cellular – the original cell divides, producing two identical daughter cells that may then be used for body growth or tissue repair. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 43 12th Edition. Pearson.  Reproduction Organismal – Reproduction of the human organism is the task of the organs of the reproductive system, which produce sperm and eggs. When a sperm unites with an egg, a fertilized egg forms, which then develops into a baby within the mother’s body. The function of the reproductive system is regulated by hormones of the endocrine system. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 44 12th Edition. Pearson.  Growth Growth is an increase in size, usually accomplished by an increase in the number of cells. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 45 12th Edition. Pearson.  Growth The scientific term for growth means “constructive activities must occur at a faster rate than destructive activities”. Constructive activities Destructive activities Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 46 12th Edition. Pearson.  Growth Hormones released by the endocrine system play a major role in directing growth. (Growth hormone, Thyroid hormone, Insulin, Androgens, and Estrogens) Disorders of pituitary growth hormone. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 47 12th Edition. Pearson. Learning Objectives Maintaining Life List 8 functions that humans must perform to maintain life List the 5 survival needs of the human body Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 48 12th Edition. Pearson.  Survival Needs ▪ The goal of nearly all body systems is to maintain life. ▪ The following factors, called survival needs, are needed to maintain life: 1. Nutrients (food) 2. Oxygen 3. Water 4. Appropriate Temperature 5. Appropriate Atmospheric Pressure Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 49 12th Edition. Pearson.  Nutrients Nutrients, which the body takes in through food, contain the chemicals used for energy and cell building. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 50 12th Edition. Pearson.  Nutrients Carbohydrates, vitamins, minerals, proteins, and fats are all vital in maintaining a healthy body. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 51 12th Edition. Pearson.  Oxygen Oxygen is needed for chemical reactions that release energy from nutrients Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 52 12th Edition. Pearson.  Oxygen Oxygen is made available to the blood and body cells by the cooperative efforts of the respiratory and cardiovascular systems. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 53 12th Edition. Pearson.  Water Water accounts for 60 to 80 percent of body weight, depending on the age of the individual. It is the single most abundant chemical substance in the body and provides the fluid base for body secretions (sweat) and excretions (urine). Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 54 12th Edition. Pearson.  Water We obtain water chiefly from ingested foods or liquids, and we lose it by evaporation from the lungs and skin and in body excretions. Sweat Water Urine Evaporation from Lung Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 55 12th Edition. Pearson.  Appropriate Temperature If chemical reactions are to continue at life sustaining levels, normal body temperature must be maintained. As body temperature drops below 37°C, metabolic reactions become slower and slower and finally stop. When body temperature is too high, chemical reactions proceed too rapidly, and body proteins begin to break down. At either extreme, death occurs. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 56 12th Edition. Pearson.  Appropriate Temperature Most body heat is generated by the activity of the skeletal muscles and cool down via blood circulating close to the skin surface or by the evaporation of sweat. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 57 12th Edition. Pearson.  Appropriate Atmospheric Pressure The force exerted on the surface of the body by the weight of air is referred to as atmospheric pressure. Higher Surface Area Lower Surface Area Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 58 12th Edition. Pearson.  Appropriate Atmospheric Pressure Breathing and the exchange of oxygen and carbon dioxide in the lungs depend on appropriate atmospheric pressure. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 59 12th Edition. Pearson.  Survival Needs ▪ Just the presence of these survival factors is not sufficient to maintain life. ▪ They must be present in appropriate amounts; excesses and deficits may be equally harmful. (eg, the food ingested must be of high quality and in proper amounts; otherwise, nutritional disease, obesity, or starvation is likely) Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 60 12th Edition. Pearson. Outlines of Chapter 1 1- An Overview of Anatomy and Physiology 2- Levels of Structural Organization 3- Maintaining Life 4- Homeostasis 5- The Language of Anatomy Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 61 12th Edition. Pearson. An Overview of Anatomy and Physiology Learning Objectives Define homeostasis, and explain its importance. Describe components of homeostatic control systems Feedback mechanisms Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 62 12th Edition. Pearson.  homeostasis The word of homeostasis describes the body’s ability to maintain the body internal conditions relatively within the normal limits (eg, body temperature which is ranges between 36.1 °C to 37.2 °C), even though the external conditions are continuously changing (eg, fever of 38 °C or higher). Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 63  Homeostasis The body maintains homeostasis when all of its needs are being adequately met and all of its organ systems are working together. Virtually every organ helps maintain homeostasis. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 64  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 65 12th Edition. Pearson. An Overview of Anatomy and Physiology Learning Objectives Define homeostasis, and explain its importance. Describe components of homeostatic control systems Feedback mechanisms Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 66 12th Edition. Pearson.  Components of Homeostasic Control Systems All homeostatic control mechanisms have three components: (1) a receptor that monitors the environmental changes (stimuli) and (2) a control center that assesses those changes and produces a response by activating (3) the effector. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 67  Components of Homeostasic Control Systems 1) The receptor monitors the change (stimulus) in the environment and sends information (input) to the control center. It sends information (input) along the afferent pathway to the control center. 2) The control center analyzes the information it receives and then determines the appropriate response or course of action. Information flows from the control center to the effector along the efferent pathway. 3) the effector, conveys the control center’s response (out-put) to the stimulus. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 68 An Overview of Anatomy and Physiology Learning Objectives Define homeostasis, and explain its importance. Describe components of homeostatic control systems Feedback mechanisms Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 69 12th Edition. Pearson. Feedback mechanism The results of the homeostatic response (feedback) influence the stimulus (the original change), either by reducing the amount of change (negative feedback), so that the whole control mechanism is shut off; or by increasing the amount of change (positive feedback), so that the reaction continues at an even faster rate Most homeostatic control mechanisms are negative feedback mechanisms. They reduce the amount of stimulus, ultimately leading to (stimulus; Glucose in blood) the shutdown of the entire control mechanism. Examples include the reduction of heart rate, blood pressure, breathing rate, or the release of hormones. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 70 Negative Feedback mechanism 71 Negative Feedback mechanism Negative Feedback - Body Cooling: Stimulus: The initial stimulus is an increase in the body's core temperature due to external factors such as hot weather or physical activity. Response: In response to the increase in body temperature, the body initiates a cooling process. Effect: The cooling process involves several responses: The body's sweat glands are activated, leading to the production and secretion of sweat onto the skin's surface. As sweat evaporates, it absorbs heat energy from the body, cooling it down. Blood vessels near the skin's surface dilate (vasodilation), allowing more blood to flow near the skin, where heat can be released. The respiratory rate may increase, promoting heat loss through exhalation. As a result of these responses, the body's core temperature decreases, returning to the normal set point. This cooling mechanism is a form of negative feedback. When the body temperature reaches the desired range, the feedback loop shuts off, helping to maintain the body's temperature within the optimal range for its proper functioning. 72 Negative Feedback mechanism 73  Negative Feedback mechanism Negative Feedback- Release of Insulin: Stimulus: After consuming a meal containing carbohydrates, blood sugar levels rise due to glucose formation during digestion. Response: The pancreas releases insulin into the bloodstream in response to high blood sugar levels. Effect: Insulin signals body cells to absorb glucose from the bloodstream, reducing blood sugar levels. Result: As a result, blood sugar levels decrease, the initial stimulus (high blood sugar) is reduced and returns to the normal range. The feedback loop shuts off. When blood sugar reaches the desired level, the pancreas reduces insulin release, maintaining blood sugar within the optimal range. Negative Feedback- Release of Glucagon: Stimulus: Low blood sugar levels (hypoglycemia). Response: The pancreas releases glucagon. Effect: Glucagon signals the liver to break down stored glycogen into glucose and release it into the bloodstream, raising blood sugar levels. Result: As blood sugar levels rise, the initial stimulus (low blood sugar) is reduced, and the feedback loop shuts off. This helps maintain blood sugar levels within a narrow, optimal range. 74  Positive Feedback Mechanisms Positive feedback (rare); Increases the amount of change (stimulus), so that the reaction continues at an even faster rate. Positive Feedback - Oxytocin Release: Stimulus: The initial stimulus is the contraction of uterine muscles during labor. Response: In response to uterine contractions, the hormone oxytocin is released. Effect: Oxytocin intensifies and speeds up contractions, leading to stronger muscle contractions in the uterus. This, in turn, causes more oxytocin to be released. The cycle continues, with oxytocin levels and contractions amplifying each other, until the baby is born. The birth of the baby ends the release of oxytocin, terminating the positive feedback mechanism. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. 75 Pearson.  Positive Feedback Mechanisms Positive feedback (rare); Increases the amount of change (stimulus), so that the reaction continues at an even faster rate. Positive Feedback - Blood Clotting: Stimulus: The initial stimulus is an increase in platelets at the injury site, triggered by blood vessel injury or damage. Response: In response to the increase in platelets, the body initiates a blood clotting process. Effect: The blood clotting process involves the activation of clotting factors (chemicals), which, in turn, further increase platelet aggregation at the injury site. As the clot forms, it releases more clotting factors, amplifying the increase in platelets and enhancing the clotting process. This positive feedback loop continues until a stable blood clot is formed, effectively sealing the injury and preventing excessive bleeding. Once the injury is sufficiently sealed and the clot is stable, the clotting process is terminated. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. 76 Pearson.  Homeostatic imbalance Homeostasis is so important that most diseases can be regarded as being the result of its disturbance, a condition called homeostatic imbalance. Conditions and diseases due to homeostatic imbalance include: Diabetes: Diabetes is characterized by the body's inability to regulate blood sugar (glucose) levels properly. In type 1 diabetes, the immune system attacks and destroys insulin-producing cells in the pancreas, disrupting glucose regulation. In type 2 diabetes, the body becomes resistant to insulin, leading to elevated blood sugar levels. Hypertension (High Blood Pressure): When the body struggles to maintain the balance of blood pressure within a healthy range, it can lead to hypertension. Persistent high blood pressure can strain the heart and blood vessels, increasing the risk of heart disease and stroke. Hyperthyroidism: An overactive thyroid gland can result in excessive production of thyroid hormones, leading to symptoms such as rapid heartbeat, weight loss, and heat intolerance. This condition disrupts the body's metabolic homeostasis. Hypothyroidism: Conversely, an underactive thyroid gland can lead to insufficient thyroid hormone production, causing symptoms like fatigue, weight gain, and cold intolerance. This condition disrupts the metabolic balance. 77 Elderly are at higher risk of Homeostatic imbalance As we age, our body organs that are responsible to maintain homeostatic balance, become less efficient in regulating the body internal conditions. These events place us at an increasing risk for illness and produce the changes we associate with aging. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 78 12th Edition. Pearson. Outlines of Chapter 1 1- An Overview of Anatomy and Physiology 2- Levels of Structural Organization 3- Maintaining Life 4- Homeostasis 5- The Language of Anatomy Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 79 12th Edition. Pearson. Why to use Terminology of Anatomy? Terminology of Anatomy​​, universally accepted terminology that allows body structures to be located and identified clearly with just a few worlds! Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 80 12th Edition. Pearson. An Overview of Anatomy and Physiology Learning Objectives Verbally describe or demonstrate the anatomical position. Use proper anatomical terminology to describe body directions, body landmarks (regions), and body planes. Locate the major body cavities, and list the chief organs in each cavity. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 81 12th Edition. Pearson.  Anatomical Position To avoid confusion, we always assume that the body is in a standard position called anatomical position. In the anatomical position, the body is erect with the feet parallel and the arms hanging at the sides with the palms facing forward and the thumbs point away from the body. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 82 An Overview of Anatomy and Physiology Learning Objectives Verbally describe or demonstrate the anatomical position. Use proper anatomical terminology to describe body directions, body landmarks (regions), and body planes. Locate the major body cavities, and list the chief organs in each cavity. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 83 12th Edition. Pearson.  The Language of Anatomy Direction (Directional terms) Landmarks (Regional terms) Structures (Body planes, sections & cavities) Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 84  Direction (Directional terms) Allow medical personnel to explain exactly where one body structure is in relation to another. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 85  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 86 12th Edition. Pearson.  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 87 12th Edition. Pearson.  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 88 12th Edition. Pearson.  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 89 12th Edition. Pearson.  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 90 12th Edition. Pearson.  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 91 12th Edition. Pearson.  The Language of Anatomy Direction (Directional terms) Landmarks (Regional terms) Structures (Body planes, sections & cavities) Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 92  Regional Terms Regions (landmarks) of the body: ▪ Anterior Body Landmarks ▪ Posterior Body Landmarks Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 93  Body Landmarks Q: Study this figure for a moment to answ er these tw o questions. Where w ould you hurt if you (1) pulled a groin muscle or (2) cracked a bone in your olecranal area? Cephalic Frontal Cephalic Orbital Upper limb Occipital (back Nasal Acromial of head) Buccal Deltoid Cervical Oral Brachial (arm) Mental Antecubital Cervical Olecranal Back (dorsal) Thoracic Scapular Sternal Antebrachial Axillary (forearm) Vertebral Pectoral Carpal (wrist) Lumbar Abdominal Manus (hand) Sacral Umbilical Digital Pelvic Gluteal Inguinal (groin) Lower limb Coxal (hip) Pubic (genital) Femoral (thigh) Patellar Popliteal Crural (leg) K EY : Sural (calf) Thorax Fibular Abdomen Pedal (foot) Back (Dorsum) Tarsal (ankle) Calcaneal Digital Plantar (a) Anterior/Ventral (b) Posterior/Dorsal Figure 1.4 The anatomical position and regional terms. This figure shows terms used to designate specific Marieb, body areas. (a) Anterior view. (b) Posterior E.N.heels view. The and are Keller, S.M., raised 2020. slightly to show the inferior plantar surface Essentials (sole) of the foot, which is actually on of surface the inferior HumanofAnatomy the body. & Physiology, 12th Edition. Pearson. 94  Anterior Body Landmarks Cephalic: related to the head Frontal: forehead Orbital: eye area Nasal: nose area buccal: cheek area oral: mouth mental: chin Cervical: neck region Thoracic: area between the neck and abdomen, supported by the ribs, sternum and costal cartilages; chest Sternal: breastbone area Axillary: armpit Pectoral: area Occurring in or on the chest Abdominal: anterior body trunk inferior to ribs Umbilical: navel Pelvic: area overlying the pelvis anteriorly Inguinal: area where thigh meets body trunk; groin area Pubic: genital region Marieb, E.N. and Keller, S.M., 2020. Essentials of Human 95 Anatomy & Physiology, 12th Edition. Pearson.  Anterior Body Landmarks Upper limb Acromial: point of shoulder Deltoid: curve of shoulder formed by large deltoid muscle Brachial: arm Antecubital: anterior surface of elbow Olecranal: posterior surface of the elbow Antebrachial: forearm carpal: wrist Lower limb Patellar: anterior knee Popliteal: posterior knee Fibular: lateral part of leg Marieb, E.N. and Keller, S.M., 2020. Essentials of Human 96 Anatomy & Physiology, 12th Edition. Pearson.  Posterior Body Landmarks Cephalic: related to the head occipital: posterior surface of head or base of skull Back (dorsal) scapular: shoulder blade region vertebral: area of spinal column lumbar: area of back between ribs and hips; the loin sacral : area between hips at base of spine gluteal: buttock Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 97  The Language of Anatomy Direction (Directional terms) Regions (Regional terms) Structures (Body planes, sections & cavities) Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 98  Body Planes & Sections ▪ A section = a cut to look at the internal structures of the body. ▪ When the section is made through the body wall or through an organ, it is made along an imaginary line called a plane. ▪ Three types of planes or sections : A sagittal section A frontal section A transverse section Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 99  Body Planes & Sections a) A sagittal section is a cut along b) A frontal section is a c) A transverse section the lengthwise, or longitudinal, cut along a lengthwise is a cut along a dividing the body into right and plane that divides the horizontal plane, left parts. Median (midsagittal) body (or an organ) into dividing the body or section: the cut is down the anterior and posterior organ into superior median plane (the right part = left parts. It is also called a and inferior parts. It is parts are equal in size. All other coronal section. also called a cross sagittal sections are parasagittal Marieb, E.N. and Keller, S.M., 2020. Essentials of Human section. sections (para= near). Anatomy & Physiology, 12th Edition. Pearson. 100  Body Planes & Sections Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th 101 Edition. Pearson. An Overview of Anatomy and Physiology Learning Objectives Verbally describe or demonstrate the anatomical position. Use proper anatomical terminology to describe body directions, body landmarks (regions), and body planes. Locate the major body cavities, and list the chief organs in each cavity. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 102 12th Edition. Pearson.  Body Cavities ▪ Two sets of internal body cavities that provide different degrees of protection to the organs within them: Dorsal (posterior) Body Cavity Ventral (anterior) Body Cavity Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 103  Dorsal Body Cavities Dorsal Body Cavity has two continuous subdivisions: ▪ The cranial cavity = space inside the bony skull (houses the brain). ▪ The spinal cavity extends from the cranial cavity nearly to the end of the vertebral column (houses the spinal cord). Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 104  Ventral Body Cavities Ventral Body Cavity is much larger than the dorsal cavity. It contains all the structures within the chest and abdomen (the visceral organs). The dome-shaped muscle, the diaphragm, divide the ventral body cavity into superior thoracic cavity and inferior abdominophelvic cavity. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 105  The Thoracic Cavity The organs in the thoracic cavity (lungs, heart, and others) are somewhat protected by the rib cage. A central region called the mediastinum houses the heart, trachea, and several other visceral organs. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 106  The Abdomino-pelvic Cavity ▪ The abdominopelvic cavity subdivided into: - Abdominal cavity, containing the stomach, liver, intestines, and other organs - Pelvic cavity, with the reproductive organs, bladder, and rectum. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 107  Areas of Ventral Body Cavities Areas of the abdominopelvic cavity: ▪ the abdominopelvic cavity can be divided into four equal regions called quadrants. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 108  Ventral Body Cavities Areas of the abdominopelvic cavity: ▪ Another system divides the abdominopelvic cavity into nine separate regions by four planes. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 109  Other Body Cavities In addition to the large closed body cavities, there are several smaller body cavities. Most are in the head and open to the body exterior. Oral cavity and digestive cavity The oral cavity, or the mouth, contains the teeth and tongue. This cavity is part of and continuous with the digestive organs, which open to the exterior at the anus. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 110  Other Body Cavities Nasal cavity Located within and posterior to the nose, the nasal cavity is part of the respiratory system. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 111  Other Body Cavities Orbital cavity The orbital cavities (orbits) in the skull house the eyes and present them in an anterior position. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 112  Other Body Cavities Middle ear cavities DOI:10.1056/NEJMcp010944 Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 12th Edition. Pearson. 113  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 114 12th Edition. Pearson. Difference between secretion and excretion Secretion is the process of cells releasing substances they've synthesized or stored to serve various functions such as cooling the body, providing lubrication, and aiding digestion. Examples include sweat, mucus, saliva, and hormones. Excretion, on the other hand, involves eliminating waste, toxins, or excess substances from the body to maintain internal balance. This process includes the removal of urine, carbon dioxide, and solid waste. Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 115 12th Edition. Pearson.  Marieb, E.N. and Keller, S.M., 2020. Essentials of Human Anatomy & Physiology, 116 12th Edition. Pearson.