pH of Blood: Balancing the Body's Vital Levels

For aspirants preparing for the National Eligibility cum Entrance Test (NEET), grasping the intricate details of human physiology is imperative. Among the fundamental concepts is the pH value of blood, which plays a pivotal role in maintaining homeostasis within the body. In this article, we delve into the significance, regulation, and clinical implications of blood pH, essential for excelling in NEET examinations.

pH, or "potential of Hydrogen," is a measure of the acidity or alkalinity of a solution, ranging from 0 to 14. A pH of 7 is considered neutral, while values below 7 are acidic and above 7 are alkaline. In the context of human physiology, maintaining an optimal pH level is vital for various biochemical processes and overall health.

What is the pH Value of Blood?

In humans, the normal pH range of arterial blood typically falls between 7.35 and 7.45. When it goes above or below this range, it can cause serious problems and could even be life-threatening if not controlled.

The pH value of blood indicates the acidic or alkaline level in the body. The normal pH of blood is essential for the proper functioning of the optimal activity of the body. Hence, because of this the body physiologically balances the blood pH range. The pH of human blood normally range from 7.35 to 7.45 for a healthy person.

How Blood pH is Maintained?

The pH of human blood is very well regulated by maintaining an acid-base balance. It is very essential to maintain this homeostasis. Various factors play their part in regulating the pH level of blood. The blood plasma pH depends on the concentrations of CO2, electrolytes and weak acids. There are two main organs, the lungs and the kidney, that are involved in the balancing of the acid-base concentrations. The mechanism by which they do so is:

• Respiratory Regulation - Lungs: They have the most significant role in exchanging gases with the blood. They remove CO2 by the gaseous exchange. The brain regulates the breathing activity and so the brain along with the lungs maintain pH value of blood by regulating the speed and intensity of the breathing.

• Renal Regulation - Kidney: Kidney is involved in the ultrafiltration of the blood and takes away the waste material from the blood and finally excretes them. Thus, in the process, any acid or base present in excess in the blood is removed thus maintaining pH of blood in human body.

Thus, the human body balances what is the pH of blood via respiration, excretion and other metabolic activities.

Buffer Systems Maintaining pH Level of Blood:

Inside your body, there are different systems that keep your blood's pH stable. They prevent big swings that could cause problems. The main ones are the bicarbonate, protein, and phosphate buffer systems. Together, they absorb extra hydrogen ions (H⁺) or hydroxide ions (OH⁻) when necessary to maintain the right balance.

Role of Carbonic Acid-Bicarbonate Buffer System:

The carbonic acid-bicarbonate buffer system is super important for keeping the pH level of blood just right. It works by a back-and-forth reaction between carbonic acid (H₂CO₃) and bicarbonate ions (HCO₃⁻). Depending on what our body needs, it can either release or soak up hydrogen ions.

Why is Blood pH Important?

Any changes that occur in the blood, due to an increase in acidic level (acidosis) or the basic level (alkalosis) is a cause of worry. This can happen due to impaired function of the lungs or the kidneys organs since they are the ones responsible for cleaning the blood of unwanted products. Changes in the normal pH of blood are generally associated with kidney failures.

Sometimes what is the pH level of blood is affected due to dysfunction of some other organs as well because of which there can be a release of the acidic and basic materials in the bloodstream. Thus, the normal pH of blood is important because it states the healthy state of internal organs of the body, specifically the kidney and the lungs.

Due to changes in the concentration of waste materials such as carbon dioxide, electrolyte and other acidic substances, the concentration of the oxygen dissolved in the blood changes and this, in turn, affects the respiration process of the cell. Once cellular respiration is damaged, the cells begin to die and can result in catastrophic events in the body such as organ failure and subsequent death. Thus, maintaining what is the normal pH of blood becomes extremely important for survival.

Causes of Abnormal pH Value of Blood

Organ dysfunction especially of the kidneys and lungs result in too high or too low levels of blood pH range. An increase in the acidic or the basic content is also indicative of grave diseases of the heart, lung or kidney and also indicate poisoning, infection, and diabetes.

High pH Value of Blood

High blood pH range is known as alkalosis (above 7.45). Under this condition, the blood becomes more and more basic as the pH goes higher than the normal pH of blood. The following are the reasons for the changes in the blood pH range taking the value higher than what is the normal pH of blood:

• Excess loss of fluid because of the increase in urination, vomiting, diarrhoea, etc is one of the primary reasons for the value to get a higher pH value of the blood. If noticed, these symptoms are some symptoms of diseases such as cholera, dengue, etc. Thus a temporary illness, in this case, is the reason for the high pH value of the blood from what is the pH of the blood.

• When kidneys are unable to remove the excess of the alkaline materials due to improper functioning, it can lead to a rise in the pH value of blood.

Low pH Value of Blood

Low blood pH range is called acidosis (below 7.35). In this condition, the blood becomes more and more acidic as the pH goes lower than the normal pH of blood. Also, this is more common than alkalosis. The main reasons the normal pH of blood goes lower are given below:

• In diabetic patients, when the body is unable to produce enough insulin, it can lead to another problem of the release of acidic ketones in the blood. This is called ketoacidosis andis another complication of diabetes. Symptoms include fatigue, confusion, and rapid breathing.

• The renal failure of the kidneys because of any disease or deteriorating health leads to metabolic acidosis. 

• Respiratory diseases such as pneumonia, bronchitis, asthma, chronic pulmonary disease in the lungs can lead to acidosis.

So, the answer to the question - why is pH level of blood important? - can be given as Blood pH range is vital for cellular respiration and intake of oxygen by the cells from the blood and also many times to diagnose diseases because these changes occur owing to organ failure because of a variety of reasons, the pH value of blood is an important determinant of the disease condition of the body. 

Conclusion

Understanding the pH value of blood is essential for NEET aspirants, as it is a fundamental aspect of human physiology and critical for maintaining overall health. Mastery of this topic involves comprehending the intricacies of blood buffer systems, regulatory mechanisms, and clinical implications of pH imbalances. By grasping these concepts, aspirants can confidently tackle questions related to pH of blood in the NEET examination and develop a deeper understanding of human physiology as a whole.