Basic Anatomy and Physiology 1 PDF

Anatomy and Physiology1 Topic 1: Introduction to the Human Body (part 1) Prepared by: Leong Yee Leng 1 Introduction Of Anatomy And Physiology Anatomy is the study of the body’s structure. Physiology is the study of body’s functi...

Anatomy and Physiology1 Topic 1: Introduction to the Human Body (part 1) Prepared by: Leong Yee Leng 1 Introduction Of Anatomy And Physiology Anatomy is the study of the body’s structure. Physiology is the study of body’s functions. 2 LEARNING OUTCOME At the end of this session, students will be able to: name the six levels of organization of the body; describe the major characteristic of each level of organization; list the 11 organ systems, identify their components; describe the major functions of each systems; define common anatomical terms; list the content of the body cavities; state 10 essential characteristic of life; define homeostasis; explain importance of homeostasis for proper body function; 3 describe a negative-feedback mechanism and give an Six levels of organization of the body 4 5  1. CHEMICAL LEVEL The lowest level of structural organization and complexity is chemical. Basic chemical characteristic are responsible for the structure and functions of life. Atoms combine to form molecules. Molecules aggregate into cells. 6  1. CELLULAR LEVEL Cells are the smallest independent units of living matter. Small to see in naked eye; can be distinguished by size, shape under microscope Cells are basic structural and functional units of organism (plants and animals) Organelles are small structures within cells that perform specific functions. 7  1. TISSUE LEVEL Tissues are composed of groups of cells of similar structure and function and the materials surrounding them. The four primary tissue types are epithelial, connective muscle, and nervous tissues. Some organs are composed of all four types of tissues 8  1. ORGAN LEVEL Organs are made up of a number of different types of tissue and have evolved to carry out a specific function. The organs are of two types called tubular or hollow organs and compact or parenchymal organs. E.g. heart, brain, liver, kidneys, endocrine gland and etc. 9  1. ORGAN SYSTEM LEVEL Organ System Organ systems consist of a number of organs and tissues that together contribute to one or more survival needs of the body. Organs are arranged into the 11 organ systems of the human body 10 11 ORGAN SYSTEMS OF THE HUMAN BODY 11 11 ORGAN SYSTEMS OF THE HUMAN BODY 12 11 ORGAN SYSTEMS OF THE HUMAN BODY 13  B 11 ORGAN SYSTEMS OF THE HUMAN BODY 14  1. ORGANISM Organ system interact to form a whole, functioning organism 15 REGIONAL AND DIRECTIONAL 16 TERMS PLANES 17 THE BODY CAVITIES 18 CRANIAL CAVITY The cranial cavity contains the brain. Its boundaries are formed by bones of the skull. Anteriorly 1 frontal bone Laterally 2 temporal bones Posteriorly 1 occipital bone Superiorly 2 parietal bones Inferiorly 1 sphenoid and 1 ethmoid bone and parts of the frontal, temporal and occipital bones 19 THE SKULL 20 THORACIC CAVITY This cavity is situated in the upper part of the trunk. Its boundaries are formed by the thoracic cage and supporting muscles. Anteriorly The sternum and costal cartilages of the ribs Laterally 12 pairs of ribs and the intercostal muscles Posteriorly The thoracic veterbrae Superiorly The structures forming the root of the neck Inferiorly The diaphragm, a dome-shaped muscle 21 CAVITIES OF THE BODY STUCTURE FORMING THE 22 WALLS CAVITIES OF THE BODY INTERNAL 23 ORGANS ABDOMINAL CAVITY This is the largest body cavity and is oval in shape It occupies most of the trunk and its boundaries The abdominal cavity is divided into the nine regions Superiorly The diaphragm, which separates it from the thoracic cavity Anteriorly The muscles forming the anterior abdominal wall Posteriorl The lumbar vertebrae and muscles forming the posterior y abdominal wall Laterally The lower ribs and parts of the muscles of the abdominal wall Inferiorly It is continuous with the pelvic cavity 24 CAVITIES OF THE BODY Organs occupying the anterior part of the abdominal cavity and diagphragm 25 CAVITIES OF THE BODY 26 Region of the abdominal cavity 27 PELVIC CAVITY Pelvic cavity is roughly funnelshaped and extends from the lower end of the abdomen cavity. Superiorly It is continuous with abdominal cavity Anteriorly The pubic bones Posteriorly The sacrum and coccyx Laterally The innominate bones Inferiorly The muscles of the pelvic floor 28 Female reproductive organs and structures in the pelvic cavity 29 Male reproductive organs and structures in the pelvic cavity 30  CHARACTERISTIC OF LIFE The most important common features of all organisms is life. 1. Organisation Refers to the specific interrelationship among the parts of an organism and how those parts interact to perform specific functions. Cellular function depends on the precise organization of large molecules. 2. Metabolism The ability to use energy and to perform vital functions. Refers to all of the chemical reactions taking place in the cells and internal environment of an organism. 31  CHARACTERISTIC OF LIFE 1. Responsiveness An organism’s ability to sense changes in its external or internal environment and adjust to those changes. Responses include actions such as moving toward food or water and moving away from danger. 2. Growth An increase in the size of cells, which produces an overall enlargement of all part of an organism. E.g. a muscle enlarged by exercise is composed of larger muscle cells than those of an untrained muscle. 32  CHARACTERISTIC OF LIFE 1. Differentiation involves changes in a cell’s structure and function from an immature, generalised state to a mature, specialised state. Though differentiation, cells develop into tissues and organs. 2. Reproduction Is the formation of new cells or new organisms. All living organism pass on their genes to their offspring. 33  CHARACTERISTIC OF LIFE 1. Movement On the cellular level, molecules move from one place to another. The diaphragm moves with every breath. The ability of muscle fibers to shorten and thus to produce movement is called contractility. 34  CHARACTERISTIC OF LIFE 1. Respiration Respiration refers to all the process involve in exchange of oxygen and carbon dioxide between the cells and the external environment. E.g. Ventilation, the diffusion of oxygen (O2) and carbon dioxide (CO2), and the transport of the gases in the blood. Cellular respiration- cell use of O2 and release CO2 in metabolism. 35  CHARACTERISTIC OF LIFE 1. Digestion Digestion is the process of breaking down complex ingested foods into simple molecules that can be absorbed into the blood and used by the body. 2. Excretion Excretion is the process that removes the waste products of digestion and metabolism from the body.it get rid of by product that the body is unable to use, 36 HOMEOSTASIS Homeostasis is the existence and maintenance of a relatively constant environment within the body. To achieve homeostasis, body must actively regulate conditions that are constantly changing. Homeostasis is maintained by control systems that detect and respond to changes in the internal environment. E.g. For a cell to function normally, the volume, temperature and chemical content of their environment must be maintained within a narrow range. 37 Homeostasis Key term in modern physiology HOMEO STASIS sameness standing still “Standing or staying the same” Homeostasis: Maintenance of nearly constant conditions in the internal environment Does not mean something set and immobile Means a condition that may vary, but which is relatively constant “Set point”; “Normal range” 38 Homeostasis Homeostasis of Oral Body Temperature Upper normal limit Norm al Set point range Lower normal limit 39 Homeostasis Essentially all organs and tissues of the body perform functions that help maintaining homeostasis Our body has the ability to “self-regulate” or “return to normal” to maintain homeostasis 40  Homeostatic Imbalances Disease is a more specific term for an illness characterized by a recognizable set of signs and symptoms. Signs are objective changes that a clinician can observe and measure; e.g., fever or rash. Symptoms are subjective changes in body functions that are not apparent to an observer; e.g., headache or nausea. Diagnosis is the art of distinguishing one disease from another or determining the nature of a disease; a diagnosis is generally arrived at after the taking of a medical history and the administration of a physical examination. Feedback System Feedback system / feedback control loop Controlled condition Stimulus Receptor/ sensor mechanism Control center / Integrator Effector 42  Some stimulus Operation of A disrupt homeostasis by Feedback Increasing or decreasing a System Controlled condition that is monitored by Receptors that send Nerve impulses or chemical signals to INPUT Usually, there is a a return to homeostasis Control center when the response receives the input brings the controlled and provides condition back to Nerve impulses or chemical signals to OUTPU normal a T Effectors that cause Response that alters the controlled condition 43 Feedback System 44 Feedback System In example B, A stimulus (drop in temperature) activates a receptor / sensor (sensory nerve fibers) that sends input to a control center (hypothalamus), which then send an output to an effector (contracting muscle). The resulting heat that is produced maintains the temperature in a “normal range” 45 Feedback System Although homeostasis is the maintenance of normal range of values, this does not mean that all variables remain within the same narrow range of value at all times. Sometimes, a deviation from usual range of values can be beneficial. E.g. during exercise- blood pressure increase Increase blood pressure helps to supply muscle cells with greater amount of O2 and nutrients needed to support increased activity during exercise. The reset range is higher and broader than the resting range. After exercise ceases, the range returns to that of resting condition. Metabolic pathway are chemical reactions driven by biological protein 46 catalyst called enzymes. E.g. glucose level in the body Feedback Systems NEGATIVE FEEDBACK POSITIVE FEEDBACK 47 Characteristic of Negative Feedback Reverses a change in a controlled condition Inhibitory Produces an action that is opposite/ reverse to the change that activated the system Responsible for maintaining homeostasis Much more common than positive feedback control system 48  Some stimulus disrupt homeostasis by Homeostasis Increasin regulation of g blood pressure Blood Pressure by NEGATIVE FEEDBACK Receptors Baroreceptors in vessels Nerve INPUT Return to impulses homeostasis Control center when response Brain interprets input brings blood and sends pressure back to Nerve OUTPU normal impulses T Effectors Heart A decrease in heart rate 49 decreases blood Homeostasis regulation of blood pressure by NEGATIVE FEEDBACK BP is the force exerted by blood as it presses against the walls of blood vessels. When the heart beats faster, BP increases and vice versa Some internal or external stimulus causes BP (controlled condition) to rise Baroreceptors, which are pressure-sensitive nerve 50 cells (the receptors) that are located in the blood Characteristic of Positive Feedback Strengthen or reinforce a change in a controlled condition Stimulatory Tend to produce destabilizing effects and disrupt homeostasis The action of positive feedback system continues until it is interrupted by some mechanism outside the system Not the usual type of feedback in the body, e.g. Positive feedback during childbirth 51 Positive feedback during immune response to an infection  Contractions of uterus wall pushing the baby’s head into cervix Interruption of cycle: Increasin Birth of baby g POSITIVE decreases stretching of cervix, FEEDBACK Stretching of Cervix thus breaking the DURING positive feedback CHILDBIRTH Receptors cycle Stretch-sensitive nerve cells in cervix Nerve INPUT Positive feedback: impulses increased stretching Control center of cervix causes release of Brain interprets input more oxytocin, and releases which results in more Oxytocin OUTPU stretching of the cervix hormone T Effectors Uterus wall contract more forcefully Baby’s body stretches cervix more 52  POSITIVE FEEDBACK DURING CHILDBIRTH 1) The first contractions of labor (stimulus) push part of the fetus into the cervix, cervical stretching (controlled condition) increases 2) Stretch-sensitive nerve cells (receptors) send more nerve impulses (input) to the brain (control center), which in turn releases the hormone oxytocin (output) into the blood 3) Oxytocin causes muscle in the wall of the uterus (effector) to contract even more forcefully 4) The contractions push the fetus farther down the uterus, which stretches the cervix even more 53 REVIEW QUESTION SAQ Define the term homeostasis. List and describe the basic components of a feedback control system. By giving one example, explain the mechanism of action of negative feedback control system. 54 SURVIVAL NEEDS OF THE BODY 55 LEARNING OUTCOME At the end of this session, students will be able to : describe the roles of the body transport system; state the roles of the nervous and endocrine systems in internal communication; state the waste materials eliminated from the body; explain activities undertaken by an individual for protection and survival. 56  COMMUNICATION 1. Transport system ensure all cells have access to the internal and external environment. 2. All communication system involve receiving, collating and responding to appropriate information. Cells communicate with each other by using chemical and electrical signals. Eg. Nerve cells produce chemical signals by which they communicate with muscle cells. Then muscle cells respond to the chemical signals by contracting or relaxing. 3. There are different systems for communicating with the internal and external environment 57  Introduction Survival need Body activities Communication Transport systems: blood, circulatory system, lymphatic system Internal communication: nervous system, Endocrine system External communication: special senses, verbal and non-verbal communication. Intake of raw materials and Intake of oxygen elimination of waste Diet Elimination of waste: carbon dioxide, urine, feces. 58 Introduction Survival need Body activities Protection and survival Protection against the external environment: Skin Resistance and immunity: non-specific defence mechanisms Body movement Transmission of inherited characteristics Reproduction 59 TRANSPORT SYSTEM Blood Adult (5-6 liters) Two parts (plasma & blood cell) Plasma Mainly water Nutrient absorbed from alimentary canal Oxygen absorbed from the lungs Chemical substances synthesised by body cells, e.g. hormones 60 Waste material produced by cells to be eliminated from the body  TRANSPORT SYSTEM (cont.) Blood cell 1. Erythrocytes(red blood cell) Transport oxygen and carbon dioxide between the lungs and all body cells. 2. Leukocytes(white blood cell) Protect the body against microbes and other potentially damaging substances that gain entry to the body 3. Platelets(thrombocytes) Blood clotting 61 CIRCULATORY SYSTEM Consist of blood vessel and the heart Blood vessel Arteries (carry blood away from heart) Veins (carry blood to the heart) Capillaries (link arteries and veins) thin cell wall, one layer cells Site for exchange substance between blood & body and tissues Blood vessels form a network that transports blood to the lungs and cells. (pulmonary & systemic circulation) 62 CIRCULATORY SYSTEM Heart Is a muscular sac Pumps blood round the body and maintains the blood pressure in the lungs and general circulation. Heart not under conscious (voluntary) control. Factor influence heart beat: exercise, emotional states, demands from muscle of moving limbs The rate of heart beat can be counted by taking the pulse. 63 CIRCULATORY SYSTEM Lymphatic system Consists of a series of lymph vessels Begins as blind ended tubes in the spaces between blood capillaries and tissue cells Similar to veins and blood capillaries but the pores in the walls of the lymph capillaries are larger. This Photo by Unknown Author is licensed under CC BY-SA 64  CIRCULATORY SYSTEM Lymphatic system Lymph is tissue fluid containing large molecules, e.g. proteins, fragments of damage tissue cells and microbes. Collection of lymph nodes situated at various points This Photo by Unknown Author is licensed under CC BY-SA-NC along the length of the lymph vessels. 65  CIRCULATORY SYSTEM Lymphatic system Lymph is filtered as it passes through the lymph nodes. (remove microbes and other materials) Sites for formation and maturation of lymphocytes, the white blood cells. This Photo by Unknown Author is licensed under CC BY-SA-NC 66 INTERNAL COMMUNICATION Communication and the nervous system Nervous system is a rapid communication system Central nervous system: Brain & spinal cord Peripheral nervous system: sensory or afferent ( provide input to the brain from organs and tissues) motor or efferent (carry output from brain to effector organs e.g. muscle & glands) 67 INTERNAL COMMUNICATION The somatic (common) senses are pain, touch, heat and cold. Arise following stimulation of specialised sensory receptor at nerve endings This Photo by Unknown Author is licensed under CC BY-SA-NC 68 INTERNAL COMMUNICATION Receptor location Muscle and joint Respond to changes in the position an d orientation of the body, maintaining posture and balance. Internal organ Maintain control of vital body function. E.g. pulse rate, respiratory rate , blood pressure. 69 INTERNAL COMMUNICATION Reflex actions Fast involuntary, and usually protective motor responses to specific stimuli. They include: Withdrawal of a finger from a very hot surface Constriction of pupils in response to bright light Control of blood pressure 70 COMMUNICATION AND ENDOCRINE SYSTEM Endocrine system consist of glands from different part of the body that secrete hormone. Hormone circulate round the body in the blood. Stimulate target glands or tissues, influencing metabolic and cellular activities and regulating body growth and maturation. Endocrine glands detect and response to levels of particular substances in the blood Changes in blood hormone levels are controlled by negative feedback mechanisms Endocrine system provide more slower and more precise control of body functions than nervous system 71 Communication with external environment Special senses Sight- eyes Hearing-ears Balance- ears Smell- nose Taste- tongue These senses are usually used together. e.g. when the smell of smoke is perceived then other senses such sight and sound are used to try and locate the source of 72 fire. COMMUNICATION WITH EXTERNAL ENVIRONMENT Verbal communication Sound is means of communication that is produced in the larynx as a result of blowing air through the space between the vocal cords during expiration. Speech is the manipulation of sound by contraction of the muscles of the throat and cheeks, and movements of the tongue and lower jaw. 73 COMMUNICATION WITH EXTERNAL ENVIRONMENT Non-verbal communication Posture and movement Skeletal system provides the body framework of the body, and movement takes place at the joints between bones. Skeletal Muscles move the skeleton attached bones to one another, spanning one or more joints in between. stimulated under conscious (voluntary) control Some may not involve the movement of bones like e.g. changes in expression. 74 INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Taken in: Oxygen , water and food Excreted: urine, faeces and carbon dioxide Intake of oxygen 21%of oxygen contain in atmospheric air Continuous supply is essential, for most chemical activities to take place in body cells. Necessary for a series of chemical reactions that result in the release of energy from nutrients 75 INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Intake of oxygen (cont.) Upper respiratory system carries air between the nose and the lungs during breathing. Air passes through a system of passages consisting of the pharynx, the larynx, the trachea, two bronchi and large numbers of bronchial passages. End in alveoli, millions of tiny air sacs in each lung; surrounded by a network of tiny capillaries and are the sites where vital gas exchange between the lungs and the blood take place. 76 77 INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Diet A balanced diet is important for health and provides nutrients, substances that are absorbed, usually following digestion, and promote body function. Nutrient include water, carbohydrates, proteins, fats vitamins and mineral salts. This Photo by Unknown Author is licensed under CC BY-SA-NC 78  INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Diet (Cont.) They are require for: 1. Maintaining water balance within the body 2. Energy production, mainly carbohydrates and fats 3. Synthesis of large and complex molecules, using mineral salts, proteins, fats, carbohydrates and vitamins 4. Cell building, growth, and repair, especially proteins 79 INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Digestion Digestive system function is to break down, or digest, food so that it can be absorbed into the circulation and then used by body cells. Consist of alimentary canal and accessory glands 80 INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Digestion (cont.) Alimentary canal- tube begins at the mouth and continues through the pharynx, oesophagus, stomach, small intestine and large intestines, rectum and anus. 81 INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Glands Accessory organs situated outside alimentary canal with ducts leading into it are : Salivary glands Pancreas liver 82  INTAKE RAW MATERIALS AND ELIMINATION OF WASTE Metabolism Consist of two groups of processes 1. Anabolism Building or synthesising large and complex substances Eg. Bone development and mineralization 2. Catabolism Breaking down substances to provide energy and raw materials for anabolism, and substances for excretion as waste. Eg. Breakdown of proteins into amino acids, glycogen into glucose, and triglycerides into fatty acids. 83  ELIMINATION OF WASTE 1. Carbon dioxide A waste product of cellular metabolism. Dissolve in body fluids to make an acid solution Excreted in appropriate amounts to maintain blood pH within normal range. 2. Urine Formed by kidneys Consist of water and waste products mainly of protein breakdown e.g. urea Maintain blood pH within the normal range micturation 84  ELIMINATION OF WASTE 1. Faeces Excreted during defecation Contains: Indigestible food residue that remains in the alimentary canal because it cannot be absorbed. Bile from the liver, which contains the waste products from the breakdown of red blood cells Large numbers of microbes 85  PROTECTION AND SURVIVAL 1. Protect against the eternal environment 2. Resistance and immunity Non specific defence mechanism Specific defence mechanism 3. Movement 4. Transmission of inherited characteristics 5. Reproduction C 86  PROTECTION AND SURVIVAL 1. Protect against the eternal environment Body surface of skin provides two layers: epidermis and dermis. Epidermis composed of several layers of cells that grow towards the surface from its deepest layer. Surface layer consist of dead cells that are constantly being rubbed off and replaced from below. Epidermis constitutes the barrier between the moist internal environment and the dry atmosphere of external environment. 87  PROTECTION AND SURVIVAL 1. Protect against the eternal environment (cont.) Dermis contains tiny sweat glands that have little canal or ducts, leading to the surface. Hairs grow from follicles in the dermis The layers of skin form a barrier against invasion by microbes, chemicals and dehydration. Dermis rich in sensory nerve endings sensitive to pain, temperature, and touch Provides sensory input from body surface to central nerveous syste 88 Regulate body temperature  PROTECTION AND SURVIVAL 1. Resistance and immunity Non specific defence mechanism Skin Mucus secreted by mucous membranes to traps microbes and other foreign materials on its and other foreign materials on its sticky surface. Gastric juice contains hydrochloric acid, which kills most ingested microbes. Specific defence mechanism Body generates a specific(immune) response against any substance it identifies as foreign. Such substances are called antigens and include: Bacteria and other microbes Cancer cells or transplanted tissue cells Pollen from flowers and plants 89  PROTECTION AND SURVIVAL 1. Resistance and immunity (cont.) Following exposure to an antigen, lifelong immunity against further invasion by the same antigen often develops. Individual gradually builds up immunity to millions of antigens. Allergic reactions are abnormally powerful immune responses to an antigen that usually poses no threat to the body. 90  PROTECTION AND SURVIVAL 1. Movement Body movement is under conscious(voluntary) control. Musculoskeletal system includes the bones of the skeleton, skeletal muscles joints. The skeleton provides the rigid body framework and movement takes place at joints between two or more bones. Skeletal muscles under the control of the voluntary nervous system, maintain posture and balance and move skeleton 91  PROTECTION AND SURVIVAL 1. Transmission of inherited characteristics Individuals with the most advantages genetic makeup are most likely to survive, reproduce and pass their genes on to the next generation. 2. Reproduction Successful reproduction is essential in order to ensure the continuation of a species and genetic characteristics from one generation to the next. 92 CONCLUSION The lowest level of structural organization and complexity is chemical. There are 10 essential characteristic of life. The process of Breaking down substances to provide energy is call catabolism. The maintenance of body temperature is by the control of a negative- feedback mechanism. The labor process is regulated by a positive-feedback mechanism. 93 94 95