The single most abundant chemical in the body is;
A) oxygen
B) protein
C) hydrogen
D) water
E) all are correct
The correct answer and explanation is:
The correct answer is D) water.
Water is the most abundant chemical in the human body, making up approximately 60% to 70% of a person’s total body weight. This percentage can vary depending on factors such as age, sex, and body composition. In general, water is essential for maintaining a wide range of physiological processes that are crucial for life.
Water plays several key roles in the body, including serving as a solvent in which many of the body’s chemical reactions take place. It is also vital for regulating body temperature through the process of sweating and evaporation. Water is involved in the transport of nutrients, waste removal, and helps maintain cell turgor (internal pressure). Moreover, water helps in the lubrication of joints and acts as a shock absorber in areas such as the brain and spinal cord.
While oxygen, hydrogen, and proteins are essential to life, water is more abundant. Oxygen, for instance, constitutes around 65% of the human body’s mass, but it is mostly bound to water molecules or present in other compounds such as proteins. Hydrogen is a significant part of water molecules, but on its own, it does not constitute the largest percentage of body mass. Proteins, though crucial for the structure and function of cells, enzymes, and tissues, represent a smaller fraction of the body’s total weight compared to water.
In summary, while all of the chemicals listed in the options are important for life, water is the most abundant chemical in the human body. Its presence is critical for the proper functioning of the body’s metabolic processes and overall homeostasis.