Blood is a blood fluid with specific functions. Give examples of the functions of blood in the
animal body and explain how the animal body defends itself by against changes in H+ ion
concentration. References included
The primary functions of blood in the animal body include transportation, regulation, and protection.
1. Transportation: Blood carries vital substances throughout the body. It transports oxygen from the lungs to all the body tissues and carries carbon dioxide, a waste product, from the tissues back to the lungs for elimination. It also transports nutrients from the digestive system to the cells, hormones from endocrine glands, and waste products to the organs of excretion.
2. Regulation: Blood helps in the regulation of body temperature by transferring heat from the internal organs to the skin's surface, where it can be dissipated. It also maintains the pH balance of the body by buffering the excess acids and bases produced during metabolic activities.
3. Protection: Blood plays a crucial role in the body's defense mechanisms. It contains white blood cells (leukocytes) that defend against pathogens, such as bacteria and viruses, by identifying and destroying them. Blood also contains antibodies and other immune system molecules that neutralize or eliminate disease-causing agents.
In terms of defending against changes in H+ ion concentration (pH), the animal body has multiple mechanisms to maintain acid-base balance:
1. Buffer Systems: Blood contains several chemical buffer systems that can quickly absorb or release hydrogen ions to prevent drastic changes in pH. The bicarbonate buffer system is one such system that helps regulate pH in the blood through the reversible reaction of carbonic acid and bicarbonate ions.
2. Respiratory Regulation: The lungs play a significant role in regulating pH. When H+ ion concentration increases (causing acidity), the brain signals the respiratory system to increase the rate and depth of breathing. This raises the elimination of carbon dioxide, which indirectly reduces the amount of carbonic acid in the blood, maintaining pH balance.
3. Renal Regulation: The kidneys are responsible for long-term pH regulation. They can reabsorb or excrete hydrogen ions and bicarbonate ions as needed to maintain pH balance in the body. H+ ion concentration is regulated by the kidneys through processes such as acid secretion and bicarbonate reabsorption.
These mechanisms work together to maintain the blood's pH within a narrow range (around 7.35-7.45), which is crucial for the normal functioning of various biochemical processes in the animal body.
References:
1. Tortora, G. J., Derrickson, B. H. (2017). Principles of Anatomy and Physiology (15th edition). John Wiley & Sons Inc.
2. Kumar, V., Abbas, A. K., Aster, J. C. (2014). Robbins Basic Pathology (9th edition). Elsevier.