Guyton and Hall, Medical Physiology, Ch 1 Notes study guide

Chp. 1  Physiology – science that seeks to explain physical and chemical mechanisms responsible for the origin, development, and progression of life Cells are the Living Units of the Body  Organ – aggregate of many different cells  All cells have certain basic characteristics that are alike o I.e. general chemical mechanisms for delivering energy are the same Extracellular Fluid – the Internal Environment  60% of the human body is fluid  Extracellular fluid – ions and nutrients needed by cells to maintain life  The ECF contains large amounts of Na, Chloride, and Bicarbonate ions o Also oxygen, glucose, fatty acids, amino acids, and carbon dioxide  The ICF contains large amounts of K, Mg, and phosphate ions Homeostasis – Maintenance of a Nearly Constant Internal Environment  Homeostasis – maintenance of nearly constant condition in the internal environments  Powerful control systems exist for maintaining the concentration of Na and H ions, as well as other important substances  Disease – often considered a state of disrupted homeostasis o Even in the presence of disease, homeostatic mechanisms remain in place  Pathophysiology – explains how various physiological process are altered in disease/injury Extracellular Fluid Transport and Mixing System – the Blood Circulatory System  ECF is transported through the body in two stages o 1. Movement of blood through the body in blood vessels o 2. Movement of fluid between blood capillaries and intercellular spaces  Circulatory System: Left lung  left heart pump  gut (nutrition and excretion)  kidneys (regulation of electrolytes)  arterial end  capillaries  venous end  right heart pump  right lung  Fluids diffuse and constituents dissolve through the capillary walls and interstitial spaces This study source was downloaded by from CourseH on :33:40 GMT -05:00 Origins of Nutrients – Respiratory System  Blood picks up oxygen in the alveoli  Alveolar membrane – membrane between alveoli and lumen of pulmonary capillaries o 0.4 – 2.0 micrometers thick o Oxygen can diffuse rapidly via molecular motion Origins of Nutrients – GI Tract  Site where dissolved nutrients (carbohydrates, fatty acids, amino acids) are absorbed from ingested food into the ECF of blood Origins of Nutrients – Liver/ Other Primarily Metabolic Organs  Not all GI absorbed substances can be used in absorbed form by cells  Liver – changes chemical compositions of substances to more usable o Along with fat cells, GI mucosa, kidneys, and endocrine glands o Also eliminates certain waste products produced in the body and ingested toxins Origins of Nutrients – Musculoskeletal System  Without muscles, the body could not move to obtain foods required for nutrition  Provides motility for protections against adverse surroundings Removal of Carbon Di