Blood Physiology: Composition, Functions, and Measurement

Blood Physiology

Blood is an essential and specialized bodily fluid that plays a crucial role in supporting organismal life. It delivers necessary nutrients and transports metabolic waste products to and from cells. Blood physiology encompasses the study of the chemical and haematological structure of blood, which can yield important information about an organism's condition and health. This article will explore various aspects of blood physiology, including its composition, functions, and the use of portable point-of-care devices for measuring blood physiology.

Composition of Blood

Blood is composed of plasma and formed components, including red blood cells (erythrocytes), white blood cells (leukocytes), and platelets. Red blood cells make up around 45% of whole blood by volume, plasma about 54.3%, and white blood cells about 0.7%. Plasma, which makes up 55% of blood fluid, comprises proteins, carbohydrates, mineral ions, hormones, carbon dioxide, and blood cells themselves. The primary protein in plasma, albumin, controls the blood's colloidalosmotic pressure.

Functions of Blood

Blood performs several important functions within the body. It carries nutrients, including glucose, amino acids, and fatty acids, to tissues. It also eliminates waste products such as urea, lactic acid, and carbon dioxide. Blood has immunological processes, such as the movement of white blood cells and the use of antibodies to identify foreign objects. Coagulation is the process by which blood is changed from a liquid to a semisolid gel to halt bleeding after a blood vessel is ruptured. Blood also has messenger activities, including hormone transfer and tissue damage signalling. It helps control the body's internal temperature and performs hydraulic actions.

Blood Physiology and Oxygen Transport

Blood physiology is closely related to oxygen transport. Oxygen is carried in the blood by the protein haemoglobin, which is found in red blood cells. When haemoglobin is oxygenated, it is bright red, and when it is not, it is dark red. In animals with lungs, arterial blood carries oxygen from the air that is inhaled to the body's tissues, while venous blood transfers carbon dioxide, which is then expelled.

Portable Point-of-Care Devices for Measuring Blood Physiology

Portable point-of-care (POC) devices are increasingly being used to measure blood physiology in various contexts. These devices have been used to evaluate organismal health and condition, monitor blood parameters in veterinary practice, and study biochemical processes in research settings. Common blood parameters measured by POC devices include glucose, pH, and electrolytes.

Conclusion

Blood physiology is a vital aspect of understanding organismal health and condition. The study of blood composition and functions has led to the development of point-of-care devices that can measure various blood parameters, providing valuable information for veterinary practice, research, and conservation efforts. As our knowledge of blood physiology continues to grow, so too will our ability to monitor and maintain the health of organisms and, ultimately, preserve biodiversity.