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.
Functions of Blood in the Animal Body:
1. Transport: Blood carries oxygen from the lungs to the cells and carbon dioxide from the cells to the lungs. It also transports nutrients, hormones, and waste products throughout the body.
2. Regulation: Blood helps regulate body temperature by distributing heat from the core to the skin's surface, where it can be released. It also maintains fluid balance by regulating the osmotic pressure and pH levels in the body.
3. Protection: Blood contains white blood cells that defend the body against pathogens, toxins, and foreign substances. It also clots to prevent excessive bleeding when blood vessels are damaged.
The Animal Body's Defense against Changes in H+ Ion Concentration:
The concentration of H+ ions in the body fluids is crucial for maintaining pH levels within the ideal range for proper body functioning. The animal body defends itself against changes in H+ ion concentration through different mechanisms:
1. Buffer Systems: Buffers are substances that can absorb or release H+ ions, reducing the impact of changes in pH. For example, the bicarbonate buffer system in the blood can release H+ ions when pH decreases and absorb them when pH increases, thus helping to maintain pH balance.
2. Kidney Regulation: The kidneys play a vital role in maintaining the body's acid-base balance. They can adjust the amount of acid or base excreted in urine, helping to regulate H+ ion concentration in the blood. When blood pH decreases, the kidneys excrete more H+ ions, and when blood pH increases, they excrete fewer H+ ions.
3. Respiratory Regulation: The respiratory system can also influence H+ ion concentration. When blood pH decreases (becomes more acidic), the respiratory system increases breathing rate and depth, allowing more carbon dioxide (which produces H+ ions when dissolved in water) to be expelled from the body. This helps decrease H+ ion concentration and increase pH.
4. Cellular Buffering: Cells also contribute to the regulation of H+ ion concentration. Inside cells, proteins and other molecules act as buffers, preventing sudden changes in pH. They can absorb or release H+ ions to maintain a stable pH environment within the cell.
Overall, the animal body has several mechanisms in place to defend against changes in H+ ion concentration, helping to maintain pH balance for optimal physiological functioning.