Human Organism PDF

THE HUMAN ORGANISM ANATOMY - the study of the structure/shape of the body and the body parts and their relationship to one another (Snell, 2007) -the scientific discipline that investigates the structure of the body (Seeley, 2010) -“ana” means to dissect or to se...

THE HUMAN ORGANISM ANATOMY - the study of the structure/shape of the body and the body parts and their relationship to one another (Snell, 2007) -the scientific discipline that investigates the structure of the body (Seeley, 2010) -“ana” means to dissect or to separate; “tomy” means to cut apart (Tortora, 2009) TWO BASIC APPROACHES TO ANATOMY: 1. SYSTEMIC ANATOMY – study of the body systems (ex: skeletal, muscular, nervous…) 2. REGIONAL ANATOMY – study of organization of the body by areas or region (ex: head, abdomen, thorax…) TWO GENERAL WAYS TO EXAMINE INTERNAL STRUCTURES OF A LIVING PERSON: 1. SURFACE ANATOMY – study of external features (ex: bony prominences which serve as landmarks for locating deeper structures) 2. ANATOMIC IMAGING – involves the use of equipments (ex: X-ray, CT Scan, MRI, Ultrasound) PHYSIOLOGY - the science of body functions (Tortora, 2009) - the scientific discipline that deals with the processes/functions of living things (Seeley, 2010) -“physio” means nature; “ology” means the study of (Tortora, ) HUMAN PHYSIOLOGY – the study of a specific organism, the human -has subdivisions: cellular physiology and systemic physiology MAJOR GOALS OF PHYSIOLOGY: 1. To understand and predict the body’s responses to stimuli (ex: “candy bar”) 2. To understand how the body maintains conditions within the narrow range of values in the presence of a continually changing environment. (ex: infection » fever » sweating) LEVELS OF STRUCTURAL ORGANIZATION: 1. CHEMICAL LEVEL – how atoms interact and combine to form molecules (ex: collagen molecules) 2. CELL LEVEL – entails the association of molecules to form cells 3. TISSUE LEVEL – group of similar cells with the same function (ex: epithelial – skin/lungs; connective – tendons; muscular – cardiac, skeletal, smooth; nervous – brain, spinal cord) 4. ORGAN LEVEL – composed of two or more type of tissues that perform specific function for the body (ex: heart, skin, urinary bladder…) 1|The Human organism  5. ORGAN SYSTEM LEVEL – group of organs that cooperate to accomplish a common purpose (The 11 major organ systems are: integumentary, skeletal, muscular, lymphatic, respiratory, digestive, nervous, endocrine, cardiovascular, urinary and reproductive) 6. ORGANISM LEVEL – any living thing that is considered as a whole (ex: bacterium, plants…) -the highest level of structural organization CHARACTERISTICS OF LIFE: 1. ORGANIZATION – specific interrelationship among the parts of an organism and how those parts interact to perform specific functions. (ex: cells composed of highly specialized organelles » disruption » loss of function and death) 2. METABOLISM – ability to use energy to perform vital functions (ex: energy from food) 3. RESPONSIVENESS – ability to sense changes in the environment and make adjustments to help maintain life. (ex: if the body temperature increases, sweat glands produces sweat which can lower body temperature back towards the normal level) 4. GROWTH – increase in size or part of an organism (ex: bone growth) 5. DEVELOPMENT – includes the changes that an organism undergoes through time, from fertilization until death. It involves DIFFERENTIATION, the change in cell structure and function from generalized to specialized. 6. REPRODUCTION – the formation of new cells/organisms HOMEOSTASIS -is the body’s ability to maintain relatively stable internal conditions even though the outside world is continuously changing. (It literally means “unchanging”) -“homeo” means the same; “stasis” means standing still -it is the existence and maintenance of a relatively constant environment within the body despite fluctuations in the environment, either internal or external. VARIABLES – body conditions that may change their value (ex: temperature, volume, chemical content…) HOMEOSTATIC MECHANISMS – maintain the body temperature near an ideal normal value (ex: sweating and shivering) SET POINT – the ideal normal value on which the variables are to be maintained NORMAL VALUES – acceptable range of values on which homeostasis can still be met. HOMEOSTATIC CONTROL MECHANISMS: 1. NEGATIVE FEEDBACK MECHANISM – regulates most of the body systems to maintain homeostasis (“negative” means any deviation from the set point is resisted or made smaller) THREE COMPONENTS TO MAINTAIN HOMEOSTASIS: a. RECEPTOR – monitors the value of a variable (ex: large blood vessels near the heart » BP) b. CONTROL CENTER – establishes the set point around which the variable is maintained and analyzes the information it receives from the receptor to determine the appropriate response or course of action. (ex: the brain is a control center) c. EFFECTOR – provides the means to control or change the value of the variable. (ex: heart) 2|The Human organism  2. POSITIVE FEEDBACK MECHANISM – the deviation from the set point becomes greater - it is not homeostatic and it is rare among healthy individuals. (“positive” implies that when a value deviates from normal, the system’s response is to make it greater) - example: massive blood loss » decrease heart rate » decrease blood pressure and volume - example: child birth or normal vaginal delivery – uterine contraction » expulsion of fetus THE LANGUAGE OF ANATOMY I. BODY POSITIONS - The normal anatomical position refers to a person standing erect with the face directed forward, the upper limbs hanging to the sides and the palms of the hands facing forward. - Supine – when a person is lying face upward - Prone – when a person is lying face downward II. DIRECTIONAL TERMS RIGHT Toward the body’s right side LEFT Toward the body’s left side INFERIOR Below SUPERIOR Above ANTERIOR Toward the front POSTERIOR (Posterus – following) Toward the back DORSAL (Dorsum – back) Toward the back (posterior) VENTRAL (Venter – belly) Toward the front (anterior) PROXIMAL (Proximus – nearest) Closer to a point of attachment DISTAL (di + sto = to be distant) Farther from a point of attachment LATERAL (Latus – side) Away from the body’s midline MEDIAL (Medialis – middle) Toward the body’s midline SUPERFICIAL (Superficialis – surface) Toward or on the surface DEEP (deop – deep) Away from the surface III. BODY PARTS AND REGIONS CEPHALIC Head FRONTAL Forehead ORBITAL Eye NASAL Nose ORAL Mouth CERVICAL Neck THORACIC Thorax PECTORAL Chest STERNAL Breastbone MAMMARY Breast ABDOMINAL Abdomen UMBILICAL Navel 3|The Human organism  PELVIC Pelvis INGUINAL Groin PUBIC Genital OTIC Ear BUCCAL Cheek MENTAL Chin CLAVICULAR Collarbone AXILLARY Armpit BRACHIAL Arm ANTECUBITAL Front of Elbow ANTEBRACHIAL Forearm CARPAL Wrist MANUAL Hand PALMAR Palm DIGITAL Fingers COXAL Hip FEMORAL Thigh PATELLAR Kneecap CRURAL Leg PEDAL Foot TALUS Ankle DORSUM Top of Foot DIGITAL Toes DORSAL Back OCCIPITAL Base of Skull NUCHAL Back of Neck SCAPULAR Shoulder Blade VERTEBRAL Spinal Column LUMBAR Loin SACRAL Between Hips GLUTEAL Buttock PERINEAL Perineum CRANIAL Skull ACROMIAL Point of Shoulder OLECRANON Point of Elbow DORSUM Back of Hand POPLITEAL Hollow behind Knee SURAL Calf PLANTAR Sole CALCANEAL Heel Nine Regions of the Abdomen: 1. UMBILICAL REGION – the area around the umbilicus » sections of the small & large intestines, inferior vena cava and abdominal aorta 2. EPIGASTRIC REGION – it is superior to the umbilical region » most of the pancreas, portions of the stomach, liver, inferior vena cava, abdominal aorta and duodenum 4|The Human organism  3. HYPOGASTRIC REGION – it is inferior to the umbilical region; it is the pubic area » portions of the sigmoid colon, urinary bladder & ureters, and portions of the small intestines 4. RIGHT AND LEFT ILIAC REGIONS – either side of the hypogastric region; inguinal regions » portions of the small and large intestine 5. RIGHT AND LEFT LUMBAR REGIONS – either side of the umbilical region; the loin regions » portions of small & large intestines and portions of the kidneys 6. RIGHT AND LEFT HYPOCHONDRIAC REGIONS – either side of the epigastric region » includes the diaphragm, portions of the kidneys, right side of the liver, spleen and part of the pancreas NOTE: The “right” and “left” regions are counted separately IV. PLANES a. SAGITTAL PLANE – runs vertically through the body; separates it into left and right -“sagittal” literally means the flight of an arrow b. MEDIAN PLANE – a sagittal plane that divides the body into equal parts c. TRANSVERSE OR HORIZONTAL PLANE – runs parallel to the surface of the ground - separates the body into superior and inferior parts d. FRONTAL OR CORONAL PLANE – runs vertically from right to left; divides the body into anterior and posterior parts LONGITUDINAL SECTION – a cut through the long axis of an organ TRANSVERSE OR CROSS SECTION – a cut at a right angle to the long axis of an organ TERMS RELATED TO MOVEMENT: a. FLEXION – takes place in a coronal or frontal plane b. EXTENSION – straightening a joint; occurs in a posterior direction c. LATERAL FLEXION – movement of trunk in a coronal plane d. ABDUCTION – the limb is moving away from the midline e. ADDUCTION – movement toward the body in the coronal plane f. ROTATION – movement of a body part around its long axis MEDIAL ROTATION – results in the anterior surface of the body part facing medially LATERAL ROTATION – results in the anterior surface of the body part facing laterally g. PRONATION OF THE FOREARM – medial rotation of the forearm in such a manner that the palm of the hand faces posteriorly 5|The Human organism  h. SUPINATION OF THE FOREARM – lateral rotation of the forearm, from the pronated position, so that the palm of the hand faces anteriorly i. CIRCUMDUCTION – combination in sequence of flexion, extension, abduction and adduction -only ball-and-socket joints are capable of this movement j. PROTRACTION – move forward k. RETRACTION – move backward l. INVERSION – movement of the foot so that the soles face medially m. EVERSION – opposite movement of the foot so that the soles face in a lateral direction V. BODY CAVITIES Three Large Cavities of the Trunk: a. THORACIC CAVITY –surrounded by the rib cage; separated from the abdominal cavity by the muscular diaphragm. MEDIASTINUM – a median structure that divides this cavity into right and left parts; it contains the heart, thymus, trachea, esophagus, etc. Lungs are found on its sides. b. ABDOMINAL CAVITY – bounded primarily by the abdominal muscles and contains the stomach, intestines, liver, spleen, pancreas and kidneys. c. PELVIC CAVITY – a small space enclosed by the bones of the pelvis and contains the urinary bladder, part of the large intestine and the internal reproductive organs. d. ABDOMINOPELVIC CAVITY – the abdominal cavity + the pelvic cavity VI. SEROUS MEMBRANES - line the trunk cavities and cover the organs of these cavities. TWO TYPES OF SEROUS MEMBRANES: a. PARIETAL SEROUS MEMBRANE – the outer part b. VISCERAL SEROUS MEMBRANE – the inner part  As an organ rubs against another organ or against the body wall, the serous fluid and smooth serous membranes reduce FRICTION. THORACIC CAVITY – contains three serous membrane-lined cavities: a pericardial cavity and two pleural cavities. PERICARDIAL CAVITY – surrounds the heart; contains pericardial fluid; located between the visceral pericardium and the parietal pericardium VISCERAL PERICARDIUM – covers the heart, which is contained within a connective tissue sac lined with the parietal pericardium. 6|The Human organism PLEURAL CAVITY – surrounds each lung, which is covered by the VISCERAL PLEURA; located between the visceral pleura and the parietal pleura; contains pleural fluid PARIETAL PLEURA – lines the inner surface of the thoracic wall, the lateral surfaces of the mediastinum, and the superior surface of the diaphragm. PERITONEAL CAVITY – a serous membrane-lined cavity contained in the abdominopelvic cavity; located between the visceral and parietal peritoneum; contains peritoneal fluid VISCERAL PERITONEUM – covers many organs of the abdominopelvic cavity. PARIETAL PERITONEUM – lines the wall of the abdominopelvic cavity and the inferior surface of the diaphragm. PERICARDITIS – inflammation of the pericardium PLEURISY – inflammation of the pleura PERITONITIS – inflammation of the peritoneum MESENTERIES – anchor the organs to the body wall and provide a pathway for nerves and blood vessels to reach the organs; consists of two layers of peritoneum fused together -connect the visceral peritoneum of some abdominopelvic organs to the parietal peritoneum on the body wall or to the parietal peritoneum of other abdominopelvic organs PARIETAL PERITONEUM – covers organs (without mesenteries and are closer to the body wall) RETROPERITONEAL – the organs stated above. (ex: kidneys, adrenal glands, pancreas…) 7|The Human organism