AN INTRODUCTION TO THE HUMAN BODY A ANATOMY AND PHYSIOLOGY DEFINED Anatomy from the Greek anatome to cut up dissect What do you mean when you speak of the anatomy of the body You are referring to the study of structures and the relationships between structures Physiology from the Greek physis nature What do you mean when you speak of the physiology of the body You are referring to the functions of the body parts These two cannot be wholly separated Why not Structure usually determines function and in turn the function of a body part usually influences its size shape and overall health B LEVELS OF STRUCTURAL ORGANIZATION What are the six levels of structural organization of the human body What comprises each level 1 2 3 4 5 6 C chemical level lowest level includes all atoms and molecules essential for maintaining life cellular level cells are the basic structural and functional units of life formed from molecules and atoms tissue level tissues are groups of similar cell types and the extracellular matrix around them cells work for a common function organ level organs are comprised of two or more different tissues each organ has a specific function and shape system level consists of an association of related organs that have a common function organismic level highest level all body parts are functioning together to comprise the individual LIFE PROCESSES All living forms carry on certain processes that distinguish them from nonliving things 1 Can you list the six important life processes of humans metabolism responsiveness excitability irritability movement growth differentiation reproduction What is metabolism Metabolism is the sum of all chemical processes in the body Metabolism can be broken down into two processes that contribute to the whole Name them Catabolism breaking down processes that provide energy by breaking large molecules into their components parts Anabolism building up processes that use energy and raw materials to build and maintain the body s structural and functional components What is responsiveness excitability irritability Responsiveness is the ability to detect and respond to changes in the external and internal environments What roles do the nervous and endocrine systems have in this process The nervous and endocrine systems detect changes in the environment then integrate and interpret those changes What roles do the muscles and glands have in this process Muscular and glandular tissues respond to input from the nervous and endocrine systems to elicit changes in the body to counteract changes in the environment What is movement and what does it include Movement includes motion of the whole body individual organs tissues cells or even organelles within cells 2 What is growth and in what two ways can it occur Growth refers to an increase in size and complexity of an individual It can occur as 1 an increase in the number and size of cells and as 2 an increase in the amount of extracellular matrix between cells pushing the cells farther apart What is differentiation Differentiation is the process a cell undergoes as it moves developmentally from an unspecialized stage to a more specialized one What is reproduction Reproduction refers either to the formation of new cells for growth repair or replacement mitosis or to the production of a new individual sexual D ANATOMICAL POSITION What is the anatomical position The subject stands upright facing the observer with feet flat on the floor arms at the sides palms and eyes facing forward E DIRECTIONAL TERMS Why do we use directional terms Directional terms are used to discuss body parts in relation to one another What are the five most commonly used directional term pairs superior versus inferior anterior ventral versus posterior dorsal medial versus lateral proximal versus distal superficial versus deep F PLANES AND SECTIONS What is a plane and how does it compare to a section A plane is an imaginary flat surface that passes through the body A section is a two dimensional surface resulting from a cut made through the three dimensional structure along one of planes described below 3 Can you list the four major planes of the body A sagittal plane is a vertical plane that divides a structure into right and left sides A frontal coronal plane divides the body or part into anterior front and posterior back A transverse horizontal or cross plane divides the body or part into superior top and inferior bottom parts An oblique plane passes through the body or part at an angle between the transverse plane and the others What are the five sections you can make through the body or a body part midsagittal parasagittal transverse frontal oblique G BODY CAVITIES What is a body cavity Body cavities are confined spaces within the body that separate internal organs and serve to protect separate and support the organs There are two dorsal and ventral Name the subdivisions of the dorsal cavity cranial cavity contains the brain vertebral spinal cavity contains the spinal cord Name the subdivisions of the ventral body cavity thoracic cavity contains the pleural cavities lungs mediastinum anterior middle pericardial cavity posterior abdominopelvic How is the ventral body cavity divided The abdominopelvic cavity is separated from the thoracic cavity by the muscular diaphragm An imaginary plane lying across the bony pelvis separates the abdomen and pelvis 4 H HOMEOSTASIS Homeostasis maintaining physiological limits Greek homoi same stasis standing still Define the term homeostasis A condition in which the body s internal environment remains within certain physiological limits What three conditions must be maintained at all times to ensure that a cell remains in homeostasis 1 2 3 optimum levels of gases ions nutrients water optimum temperature optimum pressure Why must the fluid bathing body cells by precisely maintained For the cells of the body to live the composition of their surrounding fluids must be precisely maintained at all times since this is the fluid with which they exchange materials Define extracellular fluid and its two major components Extracellular fluid ECF is that fluid outside of cells 1 Interstitial fluid intercellular or tissue fluid is that fluid filling the narrow spaces between the cells 2 Plasma is the fluid components of the blood What is intracellular fluid Intracellular fluid is the fluid within cells Describe then why interstitial fluid is considered to be the internal environment There is constant movement of