University:
Lehman College
Course:
BIO 410 | Cell Physiology and Biochemistry
Academic year:

2023
Views:

694

Pages:

4
Author:

Finnegan Le

Homeostasis Definition: It is defined as a self-regulating process by which a living organism can maintain internal stability while adjusting to changing external conditions. It is not a static process. It is a dynamic process that can change internal conditions as required to survive external challenges. 60% of the human body is water: ICF (Intracellular Fluid): Fluid inside the cell. It contains 40% water. ECF (Extracellular Fluid): It contains 20% water. ECF is the internal environment and is divided into: Interstitial Fluid (CSF): 15% Plasma: 5% All cells in the body live in the internal environment, which is ECF. ECF contains nutrients, ions, and all other substances necessary for the survival of the cells. Homeostasis is not the responsibility of a single system but involves all the organ systems of the body, operating cooperatively to effect internal constancy. Each cell contributes toward the maintenance of homeostasis. What Needs to Be Maintained Constant in Internal Environment Concentration of oxygen and carbon dioxide. pH of the internal environment. Concentration of nutrients and waste products. Concentration of salt and other electrolytes. Volume and pressure of extracellular fluid. Role of Various Systems of the Body in Homeostasis Cardiovascular System: Transports oxygen, carbon dioxide, nutrients, and hormones to and from the body cells. Helps regulate pH and temperature. Provides protection against diseases. Respiratory System: Exchanges gases between atmospheric air and blood. Adjusts the pH of body fluids. Nervous System: Controls body activities requiring rapid response. Detects and initiates reactions to change in the external environment. Generates nerve impulses (Action potentials) that provide communication and regulation of most body tissues. Endocrine System: Regulates activities requiring duration. Regulates the activity and growth of target cells in the body. Regulates metabolism. Excretory System: Eliminates waste products from the body. Maintains blood pH, volume, pressure, osmolarity, electrolyte composition, etc. Produces hormones. Skeletal System: Provides support, protection, and the production of blood cells. Muscles produce body movements and produce heat to maintain body temperature. Gastrointestinal System: Breaks down food into absorbable form. Absorbs various nutrients. Eliminates waste from the body. Integumentary System: Protects the body and regulates body temperature. Allows the sense of pleasure, pain, and other stimuli in the external environment. Reproductive System: Maintains homeostasis by making the offspring survive. Plays a very important role in the development of sexual characteristics and physiology of the offspring. Components of a Homeostatic System Sensor: Detects the stress. Control Center: Receives information from the sensor and sends a message to adjust the stress. Effector: Receives the message from the control center and produces the response which re-establishes homeostasis.