Anatomy and Physiology Ch. 1 Study Guide Essay

Anatomy the study of the imprint or structure and arrangement of be parts and their relationshipsPhysiology the study of the turns of the underframey parts or structures and their relationships in maintaininglife processes.Levels of Structural OrganizationThe human body consists of directs of structural organization that are associated with one another. in that respect are six takes of structural organizationI. chemic level It is the simplest level and it includes all of the chemical substances essential for maintaining life. These substances are made up of atoms.An atom is thesmallest unit of matter. Matter is anything that takes up space and has mass.Atoms combine to form molecules, which may be simple orcomplex. Different types of molecules combine to form oranelles (little organs). Organelles are limited structures that carry out specific functions.2. cellular level The cell is the basic unit of structureand function and of life. Cells vary in size, shape, and functio n and may contain many types of organelles.3. weave level Tissues are groups of similar cells thatperform a specific function.There are four major types of tissues in the human bodya.epithelial tissue It is ensnare lining bodycavities and covers the surface of the body.It functions inprotection, secretion, and excretion.b. connective tissue It is found on the surfaces ofand in organs and tissues and functions in protection, support, and attaching organs and tissues to each other and to the walls of body cavities.c. muscle tissue It functions in the movement ofbody parts and organs, and in the movement of substances passim the body.There are lead major types of muscle tissue(1)skeletal muscle It is found attached to andcovering bones and it functions in bodymovement.(2)cardiac muscle It is located in the heartwall and functions in the contraction andrelaxation of the heart as it beats.(3)smooth muscle It is located in the walls ofinternal or visceral organs and it functionsi n moving substances throughout the body.d.nervous tissueIt is located in the learning ability andspinal heap, and extends to various tissues and organs.Itfunctions in transmitting electrical or nerve impulses from the external and internal environments to the brain and spinal cord where it is interpreted and a response occurs.4. organ level Organs are groups of two or more types oftissue working unitedly to perform a specific function.5. organ system level sTstems are groups of organsthat work closely together to perform a common function.There are eleven organ systems in the human bodyaog.h.i.j.k.integumentary systemmuscular systemskeletal systemnervous systemendocrine gland systemcardiovascular systemlymphatic systemrespiratory systemdigestive systemurinary systemreproductive system6. organismal level It is the highest level of structuralorganization and it consists of groups of organ systems working together to maintain body structure and function. Organ systems work toge ther to maintain an internal environment that is fairly constant, stable, or balanced. This is referred to as homeostasis (to stay the same). Changes do occur, but within very narrow ranges or limits.HomeostasisBody parts or structures function efficiently in maintaining metabolic processes and when the survival needs are within certain limits or optimum levels.The survival needs includewater,oxyqen, nutrients, an appropriate bod temperature, and atmospheric pressure. Water is necessary for chemical reactions, excretion, and secretion.Oxyqen is required for many of the metabolicreactions that break down nutrients and provide energy. Nutrients provide energy for cells and cell processes. Bod temperature moldiness be maintained within a certain range for chemical reactions and cell processes to perform efficiently.If the body temperature falls in like manner low or increases too high, chemical reactions will slow down or may stop. Atmospheric pressure is the force of air on the body surface by the cargo of air. It is important in breathing and in the exchange of oxygen and carbon dioxide in the lungs. To maintain homeostasis there are control mechanisms. Control mechanisms consist of three partsi. receptor It responds to sensory stimulifrom theinternal and external environments. The information is sent along afferent pathways to the control center.2. control center It consists of the brain and spinal cord which interpret and analyze the information and determine an appropriate response.Information is then sent along efferentpathways to the effector.3. effector It consists of tissues, organs, or glands that perform a drive response to the original stimulus that was received by the receptor. The response involves a feedback mechanism. If the response slows down or inhibit the stimulus it is a neqative feedback mechanism. If the response speeds up or enhances the stimulus, it is a positive feedback mechanism.Most controlmechanisms for homeostasis in the human body are negative feedback mechanisms.