Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Anatomy – the study of the structure of body parts and their relationships to one another Physiology – the study of the function of the body’s parts Physiology (function) is only explainable in terms of the underlying anatomy (structure) Anatomy & Physiology are inseparable because function always reflects structure Examples: ◦ Heart is able to pump blood (function) because it is a thick, muscular organ with hollow tubes to transport ◦ Bones provide support and structure (function) because they contain hard mineral deposits Gross or Macroscopic – studies large body structures seen with the naked eye (i.e. heart, lungs, kidneys) ◦ Systemic – gross anatomy of the body studied by system (ex. Organs of cardiovascular system) ◦ Regional- gross anatomy of the body studied by region of the body (ex. Organs located in abdomen) Microscopic- studies structures of the body too small to be seen with the naked eyes ◦ Cytology – study of the cells ◦ Histology- study of tissues Developmental – studies changes in the body over the course of a lifetime ◦ Embryology- changes in an individual from conception to birth Chemical – atoms molecules macromolecules organelles Cellular – cells are smallest unit of life Tissues – groups of cells with similar functions (epithelial, connective, muscle, nerve) Organ – made up of different types of tissues that work together to perform a specific function Organ system – consists of different organs that work closely together Organism – total of all structures working together Smooth muscle cell Molecules 2 Cellular level Cells are made up of molecules. Atoms 1 Chemical level Atoms combine to form molecules. 3 Tissue level Tissues consist of similar types of cells. Smooth muscle tissue Heart Cardiovascular system Blood vessels Epithelial tissue Smooth muscle tissue Connective tissue 4 Organ level Organs are made up of different types of tissues. Blood vessel (organ) 6 Organismal level The human organism is made up of many organ systems. 5 Organ system level Organ systems consist of different organs that work together closely. Need to know basic structures and function for: ◦ ◦ ◦ ◦ ◦ ◦ ◦ ◦ ◦ ◦ ◦ Integumentary Skeletal Muscular Lymphatic/Immune Respiratory Digestive Nervous Endocrine Cardiovascular Urinary Reproductive 1. Maintaining boundaries – the internal environment remains distinct from the external environment ◦ Cellular level – accomplished by plasma membranes; selective permeability ◦ Organismal level – accomplished by the skin (i.e. the integumentary system) 2. Movement Locomotion (i.e. running, swimming) with help of muscular and skeletal systems Propulsion of food, blood, urine (peristalsis) contractility – shortening of muscle cells 3. Responsiveness – ability to sense changes in the environment and respond to them 4. 5. Digestion – breakdown of ingested food to absorb nutrients Metabolism – all the chemical reactions that occur in the body 6. Controlled by nervous system Reflexes (ex. Pull hand away from hot stove, cut foot on broken glass and pull back) Catabolism- breaking down substances into simpler building blocks Anabolism- building more complex structures from simpler substances Excretion – removal of wastes from the body 7. Reproduction ◦ Cellular – an original cell divides and produces two identical daughter cells (mitosis) ◦ Organismal – sperm and egg unite to make a whole new person (reproductive system) 8. Growth – increase in size of a body part or of the organism Increase # of cells 1. 2. 3. 4. 5. Nutrients – needed for energy and cell building (food: carbs, proteins, lipids) Oxygen – necessary for metabolic reactions (releases energy from food in cell respiration) Water – provides the necessary environment for chemical reactions Normal body temperature – necessary for chemical reactions to occur at life-sustaining rates (37 Celsius; 98.6 Fahrenheit) Atmospheric pressure – required for proper breathing and gas exchange in the lungs KEY CONCEPT: All survival needs must be present to maintain life BUT must be in appropriate amounts…excesses and deficits may be harmful Homeostasis – ability to maintain a relatively stable internal environment in an everchanging outside world ◦ Does not mean “unchanging” or “static” but rather a “dynamic state of equilibrium”, or balance, where conditions may vary but within narrow stable limits Variables-factor or event being regulated in the body The three interdependent components of control mechanisms respond to changes in variables: ◦ Receptor – monitors the environment and responds to changes (stimuli) in it; DETECTS CHANGE ◦ Control center – receives input from receptor, determines the set point at which the variable is maintained; and determines appropriate response ◦ Effector – receives directions from control center and provides the means to respond to stimuli 3 Input: Information sent along afferent pathway to Control center Receptor (sensor) 4 Output: Information sent along efferent pathway to Effector 2 Change detected by receptor 5 1 Stimulus: Produces change in variable Variable (in homeostasis) Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis Negative Feedback= depresses or shuts off the original stimulus ◦ Causes the variable to change in the opposite direction of the original change ◦ Return to norm or “ideal” value ◦ Most homeostatic control mechanisms are negative feedback to prevent sudden, severe changes in body ◦ Examples: regulation of body temperature & heart rate Positive Feedback= enhances the original stimulus so the activity is amplified (waterfall effect) ◦ Causes the variable to change in the same direction as the original disturbance ◦ Usually control infrequent events such as labor contractions or blood clotting Set point Control center (thermostat) Signal wire turns heater off Receptor-sensor (thermometer in Thermostat) Heater off Effector (heater) Response; temperature drops Stimulus: rising room temperature Balance Response; temperature rises Stimulus: dropping room temperature Heater on Set point Effector (heater) Receptor-sensor (thermometer in Thermostat) Signal wire turns heater on Control center (thermostat) NEGATIVE FEEDBACK POSITIVE FEEDBACK Disturbance of homeostasis or the body’s normal equilibrium Overwhelms the usual negative feedback mechanisms allows destructive positive feedback mechanisms to take over Often results in disease ◦ Pathology: study of disease conditions that occur Special terminology is used to prevent misunderstanding when discussing the body Exact terms are used for: ◦ ◦ ◦ ◦ Position Direction Regions Structures Provides standard frame of reference when using directional terms to describe the body Body erect, feet slightly apart, palms facing forward, thumbs point away from body “standing at attention” but with palms forward and hands out Allow us to explain where one body structure is in relationship to another Superior (Cranial)– toward the head Inferior (Caudal) – away from the head Anterior (Ventral) – toward the front of the body Posterior (Dorsal) – toward the back of the body Medial – toward the midline Lateral–away from the midline **Right and left refer to those sides of the person being viewed…NOT those of the observer SUPERIOR SUPERIOR The mouth is INFERIOR to the eyes INFERIOR INFERIOR The forehead is SUPERIOR to the nose The heart is POSTERIOR to the sternum The sternum is ANTERIOR to the spine The heart is MEDIAL to the arm MEDIALLATERAL The arms are LATERAL to the chest LATERALMEDIAL Proximal – closer to the trunk of the body Distal – farther from the trunk of the body Superficial (External) – toward the body surface Deep (Internal) – away from the body surface The elbow is PROXIMAL to the wrist The knee is DISTAL to the thigh The skin is SUPERFICIAL to the skeletal The lungs are DEEP to the skin 2 Regions ◦ Axial – includes the head, neck, and trunk ◦ Appendicular – consists of appendages or limbs, which attach to the body’s axis Sagittal – vertical plane that divides the body into right and left parts ◦ Midsagittal or medial – sagittal plane that lies on the midline ◦ Parasagittal- offset/parallel to the midline Frontal or coronal – vertical plane that divides the body into anterior (front) and posterior (back) parts Transverse or horizontal (cross section) – horizontal plane that divides the body into superior and inferior parts Oblique section – cuts made diagonally ◦ (seldom used) Body Cavities are spaces closed to exterior of body within the body that contain organs, or viscera 2 Main Sets: ◦ Dorsal cavity- protects the nervous system; 2 subdivisions Cranial cavity – within the skull; encases the brain Vertebral/Spinal cavity – runs within the vertebral column; encases the spinal cord Cranial and spinal cavity are continuous with one another; posterior to ventral cavity Ventral cavity is located anterior to the dorsal cavity Ventral Cavity- Contains the internal organs (viscera); 2 subdivisions ◦ Thoracic superior to the abdominopelvic cavity Contains lungs (pleural cavity), heart (pericardial cavity), and mediastinum (trachea + esophagus) Surrounded by ribs and muscles of the chest ◦ Abdominopelvic – Most vulnerable because there are no bones to protect the organs here Separated from thoracic by diaphragm Contains abdominal cavity (stomach, intestines, spleen, liver) and pelvic cavity (bladder, rectum, some reproductive organs) Cranial cavity (contains brain) Thoracic cavity (contains heart and lungs) Dorsal body cavity Diaphragm Vertebral cavity (contains spinal cord) Abdominal cavity (contains digestive viscera) Key: Pelvic cavity (contains bladder, reproductive organs, and rectum) Dorsal body cavity Ventral body cavity (a) Lateral view Key: Cranial cavity Dorsal body cavity Ventral body cavity Vertebral cavity Thoracic cavity (contains heart and lungs) Superior mediastinum Pleural cavity Pericardial cavity within the mediastinum Diaphragm Abdominal cavity (contains digestive viscera) Abdominopelvic cavity Ventral body cavity (thoracic and abdominopelvic cavities) Pelvic cavity (contains bladder, reproductive organs, and rectum) (b) Anterior view Figure 1.9b Parietal serosa -lines internal body cavity walls; folds over on itself to form visceral serosa Visceral serosa- covers the internal organs; wraps each individual organ Serous fluid -separates the 2 layers of serosa (parietal and visceral); allows organs to slide without friction Function: - Provide protection to organs - Reduce friction between organs and cavity walls Figure 1.10a Figure 1.10b Oral and digestive – mouth and cavities of the digestive organs Nasal –located within and posterior to the nose Orbital – house the eyes Middle ear – contains bones (ossicles) that transmit sound vibrations Synovial – joint cavities 1. 2. 3. 4. 5. 6. 7. 8. 9. The nine abdominopelvic regions include: Right hypochondriac region Epigastric region Left hypochondriac region Right lumbar region Umbilical region Left lumbar region Right iliac region Hypogastric region Left iliac region X-ray: directs short wavelength electromagnetic waves at the body ◦ Dense structures appear light (absorb x-ray), while hollow organs and fat appear dark (absorb less) Used for bones and tumors CT (computed tomography): uses x-rays; produces cross-sectional images of the body ◦ Used for brain and abdomen ◦ CAT scan type of CT PET (positron emission tomography): used to observe metabolic processes ◦ A form of nuclear medicine; patient is given an injection of radioisotopes Sonography (ultrasound): uses sound waves to create an image of body organs ◦ Imaging of choice in obstetrics MRI (magnetic resonance imaging): used to image soft tissue structures ◦ Uses a huge magnet; distinguishes the water content of body tissues