Physiology - Fall 2023 - Faculty of Pharmacy PDF

F A C U L T Y O F P h a r m a c y F A L L 2 0 2 3 Faculty of Pharmacy Physiology Introduction to Physiology Total Body Water &...

F A C U L T Y O F P h a r m a c y F A L L 2 0 2 3 Faculty of Pharmacy Physiology Introduction to Physiology Total Body Water & Homeostasis Dr. Doaa Abdel Wahed Lecturer of Physiology Faculty of Medicine 2 Faculty of Pharmacy Intended Learning Outcomes - By the end of this lecture, you should be able to: 1. Define Physiology. 2. Recognize the physiology of the cell. 3. Know the distribution of total body water. 4. Distinguish the difference between the composition of the ECF & ICF. 5. Outline the factors affecting water balance. 6. Define Homeostasis. 7. List the factors that must be homeostatically maintained in the internal environment of the body. 8. Outline how the body systems contribute to homeostasis. 3 Faculty of Pharmacy Physiology Physiology is the study of NORMAL body functions. The study of the normal functions of a living organism. 4 Faculty of Pharmacy Human Body Parts 5 Faculty of Pharmacy The Physiology Of The Cell - Is the basic unit of both structure and function. - Cell is the smallest structure of living matter, which is capable of functioning as an independent unit i.e., cell, is structural & functional unit of tissues. 6 Faculty of Pharmacy BODY COMPOSITION - In adult male, body weight is 70 kilograms: 18 % of his body weight proteins 15 % of his body weight fats 7 % of his body weight minerals 60 % of his body weight water Faculty of Pharmacy Factors Affecting Total Body Water Physiological Factors: Amount of fat: Water content decreases with obesity. Sex: Females have lower water content than males. Age: Total body water decreases with age. Faculty of Pharmacy Distribution Of Body Water (Fluids) (1) Intra-Cellular fluid (ICF): 2/3 Water inside cells. (2) Extra-Cellular fluid (ECF): 1/3 Water outside cells. It is subdivided into: - Interstitial fluid (ISF) 3/4 - plasma 1/4 9 Faculty of Pharmacy 10 Faculty of Pharmacy COMPOSITION OF BODY FLUIDS - The fluid inside the cells of the body, intracellular fluid (ICF), is very different from that outside the cells, the extracellular fluid (ECF). - Such difference in composition is extremely important to the life of the cell. Faculty of Pharmacy - ECF contains large quantities of Na+ & small quantities of K+, the main ECF cation is Na+. - ECF contains large amount of Cl- & small amount of phosphates & proteins, the main ECF anion is Cl-. - ICF contains large quantities of K+ & small quantities of Na+, the main ICF cation is K+. - ICF contains very large amounts of phosphates & proteins & small amount of Cl-, the main ICF anions are phosphates & proteins. Faculty of Pharmacy Water Balance Sources of water gain Sources of water loss Under normal body activity and moderate climate Drinking (1300 ml). Urine (1500 ml). Water contained in solid food Insensible water loss via respiratory (800 ml). tract & skin Water derived from oxidative (900 ml). metabolism in our body (400 ml). Stool (100 ml). Under pathological conditions e.g.: In patients receiving Patients have severe vomiting and Intra-venous infusions. diarrhea Faculty of Pharmacy * Water balance means water gain = water loss * If water loss > water gain Dehydration. * If water gain > water loss Overhydration = water loaded Both overhydration & dehydration are serious conditions. Faculty of Pharmacy Which is more in our body ECF or ICF ????? The plasma is part of ????? What is meant by overhydration ????? What are the causes of dehydration ????? 15 Faculty of Pharmacy 16 Faculty of Pharmacy Homeostasis 17 Faculty of Pharmacy Homeostasis (Homeo = same - Stasis = staying) - It is the maintenance of constant conditions in the internal environment of the body. - The internal environment is the ECF. - It is essential to maintain constant conditions in this internal environment, since normal cell function depends upon this constancy. Faculty of Pharmacy External Environment and Internal Environment External Environment: is the surrounding environment in which the organism lives. Internal Environment: is the fluid that surrounds the cells i.e. ECF. 19 Faculty of Pharmacy The Advantages of Homeostasis (1) Increased chances of survival. (2) Allows freedom to live in a variety of conditions. (3) Permit proper functioning of the brain. Almost all diseases are failures of homeostasis. Faculty of Pharmacy Factors in the Internal Environment that must be Homeostatically maintained: pH: 7.4 Blood volume: 5 L. Blood pressure: 120/80 mmHg Temperature: 37 ◦C Faculty of Pharmacy The body Systems and Contribution to Homeostasis The circulatory system: - Continuous movement of blood in the circulatory system. The respiratory system: - While blood passes through the lungs, it picks up oxygen and releases carbon dioxide into the alveoli. Faculty of Pharmacy The musculoskeletal system: - This system helps the body to move to obtain its requirements as food and to move away from adverse surrounding (protective function). The nervous system: - Sending impulses to muscles to control movement. The endocrine system: - Regulates cellular functions by hormones. Faculty of Pharmacy The digestive system: - Different dissolved nutrients are absorbed into the blood through the wall of the gastrointestinal tract. The kidneys and urinary system: - During the passage of blood through the kidneys, the wastes and excesses of water are removed. The immune system: - Defends against foreign invaders. Faculty of Pharmacy The Skin: - Serves as an outer protective barrier. The Reproductive: - Continuity of species. The nervous and the endocrine systems are the 2 major regulatory systems Faculty of Pharmacy External versus Internal environment ????? What are the advantages of homeostasis ????? What is the role of the kidney in Homeostasis ????? What are the regulatory systems in the body ????? 26 Faculty of Pharmacy 27 Faculty of Pharmacy Thank you 28