Chapter 1

Keys Skills for Success Mastery of the medical terminology Development of excellent observation skills

Anatomy is the study of the structure of body parts and their relationships to each other Physiology is the study of the function of the body parts

Topics of Anatomy Gross (Macroscopic) – the study of structures large enough to see with the unassisted eye - 3 subcategories: Regional, Systemic and Surface Microscopic - study of structures too small to be seen with the unassisted eye - 2 sub categories: Cytology and Histology

Developmental – study the changes of structures over the course of a lifetime - Embryology Specialized Branches – - 3 subcategories: Pathological, Radiographic, and Molecular Biology

Topics of Physiology Covers several topics; most of which are particular to the function of a specific organ system Focuses on the cellular and molecular events

Complementarity of Structure & Function Function is dependent on the structure and the form of the structure relates to its function Addage: “Form vs. Function”

Levels of Organization 6 different levels of organization Each level has specific functions and features

Chemical Level of Organization Atoms are the tiny building blocks of matter which combine to form molecules Molecules combine in specific ways to form organelles, which are the basic unit of living cells

Cellular Level of Organization Cells are the smallest unit of life Vary widely in size and shape based on the function of the cell

Tissue Level of Organization Groups of cells that perform a common function

Organ Level of Organization A groups of discrete structures composed of at least 2 groups of tissue that work together to perform a specific function Examples include: Lungs, Heart, Liver, Small Intestine

Organ System Level of Organization Group of organs that work in conjunction with each other to accomplish a specific goal or purpose Examples are: Skeletal, Digestive, Respriratory, Circulatory, Muscular, Nervous, Reproductive

Organismal Level of Organization The total of all the level working together to promote and maintain life

Maintaining Life Necessary Life Functions - Maintaining boundaries - Movement - Responsiveness - Digestion - Excretion - Reproduction - Growth

Survival Needs - Nutrients - Oxygen - Water - Normal Body Temperature - Atmospheric Pressure

Homeostasis Homeostasis - the ability of the body to maintain a relatively constant internal environment regardless of the external environment. Most homeostatic imbalance is result of disease

Homeostatic Control Components - Variable: the regulated factor or event - Receptor: Structure that monitors changes in the environment and sends information to the control center - Control Center: Structure that determines the set point for the variable, analyzes input and coordinates an appropriate response - Effector: Structure that carries out the response directed by the control center

Negative feedback mechanisms - Most homeostatic control mechanisms are classified as negative feedback mechanisms - Causes the variable to change in a way the opposes the initial change - Nervous and Endocrine systems are importance to the maintenance of homeostasis - The goal is to prevent sudden, severe changes in the body

Positive Feedback Mechanisms - Causes the variable to change in the same direction and the original change resulting in a greater deviation for the start point - Typically activate self perpetuating events - Most are not related to the maintenance of homeostasis

Language of Anatomy- must know the terms on pgs 12 & 15 Anatomical Position and Directional Terms - Directional terms are used to explain EXACTLY where on body part is in relation to another - Anatomical Position is the position in which the body is erect, palms face forward, and thumbs point away from the body - Terms left and right refer to the sides of the person viewed not the observer - Anatomical position is ALWAYS assumed regardless of the position of the body

Regional Terms - Two fundamental divisions of the body - Axial region includes the head, neck and trunk - Appendicular region include the upper and lower limbs - Regional terms designate specific areas within the axial and appendicular divisions

Body Planes and Sections - Planes are flat surfaces that lie at right angles to each other - Frontal plane: a vertical plane the separates the body into anterior and posterior parts - Transverse plane: a horizontal plane that separates the body from right to left into superior and inferior parts - Sagittal: vertical plane that separates the body into left and right parts - Median (midsagittal): lies exactly along the body’s midline - Parasagittal: lies offset from the midline of the body

Sections are cuts made along specific planes Transverse: is a cut made along the transverse plane Oblique: is a cut made at anglesbetween the horizontal and vertical planes

Body Cavities and Membranes - Body cavities are spaces w/in the body that are closed to outside and contain internal organs - The dorsal cavity is the space that houses the central nervous system and has two subdivisions - Cranial Cavity- Vertebral / Spinal Cavity - The ventral cavity is the anterior space that is larger and has two subdivisions - Thoracic Cavity- Abdominopelvic Cavity

Ventral body cavity houses the body organs or viscera Membranes -Serosa membranes cover the inner walls of ventral cavity and outer surfaces of the organs - Parietal serosa line body cavity walls and is named for the specific cavity it is associated with - Visceral serosa cover the outer surfaces of organs and is named for the specific organ associated with Secrete and are separated by a thin layer of lubrication called Serous Fluid, allows organs to slide without friction in the cavity

Abdominpelvic Region and Quadrants - There are 9 abdominopelvic regions used by anatomists - There are 4 quadrants used by medical personnel

Other body cavities - Oral and digestive: extend from the mouth through the anus - Nasal: within and posterior to the nose - Orbital: houses the eyes - Middle ear: house the ear bones and transmit sound - Synovial: joint cavities that secrete lubricating fluid, found in all movable joints