Introduction to Physiology

Introduction to Physiology

• Physiology studies how living organisms function, examining physical and chemical processes from molecular to organismal levels.
• It's an interdisciplinary field drawing knowledge from chemistry, physics, biology, and anatomy.
• It encompasses organ systems and their interactions, including the nervous, endocrine, cardiovascular, respiratory, and digestive systems.
• Physiology research aims to understand disease, develop therapies, and improve human health.

Blood

• Blood is a specialized connective tissue circulating throughout the body.
• It consists of:
  • Plasma: a liquid portion containing water, proteins (albumins, globulins, fibrinogen), electrolytes, nutrients, and waste products.
  • Formed elements: cells and fragments suspended in plasma, including:
    • Erythrocytes (red blood cells): carry oxygen using hemoglobin, a protein that binds and transports oxygen. Their biconcave shape maximizes gas exchange surface area.
    • Leukocytes (white blood cells): part of the immune system, fighting infection and disease. Different leukocytes have diverse functions like phagocytosis and antibody production.
    • Thrombocytes (platelets): cell fragments initiating blood clotting by releasing factors for the clotting cascade.
• Blood functions include:
  • Transporting gases (oxygen and carbon dioxide), nutrients, hormones, and waste products.
  • Regulating body temperature, pH, and fluid balance.
  • Providing disease protection through the immune system, including phagocytosis and antibody creation.
  • Blood clotting, the process of forming clots to prevent bleeding.
• Blood volume and composition are carefully regulated for homeostasis. Variations can cause health issues.
• Blood characteristics like viscosity, pH, and osmotic pressure are crucial for function.
• Blood pressure, driven by the heart's pumping, delivers blood to tissues. Maintaining healthy blood pressure is key for preventing health complications.
• Blood types are determined by specific antigens on red blood cell surfaces. Matching blood types is vital for transfusions to avoid lethal reactions.
• Blood disorders such as anemia, leukemia, and hemophilia can impact blood component function and overall health.