Bioelements and Biomolecules: Essential Components of Life

Bioelements: The Building Blocks of Matter

Bioelements are the chemical elements that make up living matter. Of all known elements, only 27 are considered bioelements. They are categorized into three types:

• Primary: Carbon (C), Oxygen (O), Hydrogen (H), Nitrogen (N), Sulfur (S), and Phosphorus (P), which are present in 98% of living organisms.
• Secondary: Calcium (Ca), Iron (Fe), Sodium (Na), and Potassium (K), present in 3.9%.
• Trace Elements: Cobalt (Co), Zinc (Zn), and Silicon (Si), present at 0.1%. These are essential; without them, organisms become ill or die.

Biomolecules: The Molecules of Life

Biomolecules are formed by the combination of bioelements. They are classified into two main groups:

• Organic: Carbohydrates, lipids, proteins, and nucleic acids (based on carbon).
• Inorganic: Water and mineral salts (not based on carbon).

Inorganic Biomolecules

Water

Water makes up 70% of the human body. Its main functions include:

1. Acting as a universal solvent for chemical reactions and substance transport.
2. Regulating body temperature.
3. Providing structural cohesion.
4. Maintaining density properties that allow life to persist in cold environments.

Mineral Salts

These exist in two forms: dissolved (ions) and solid (forming structures like bones, cartilage, shells, and horns).

Organic Biomolecules

Carbohydrates

Also known as sugars or hydrates of carbon, they serve as:

• Quick energy: Glucose.
• Energy reserves: Glycogen in animals and starch in seeds and tubers.
• Structural components: Cellulose.

Carbohydrates are classified as:

• Monosaccharides: Formed by one molecule, such as glucose or fructose (fruit sugar) and lactose (milk sugar).
• Polysaccharides: Formed by the union of several monosaccharides, including starch, glycogen, cellulose (the most abundant biomolecule), and chitin.

Lipids

Lipids are insoluble in water but soluble in organic solvents like alcohol or acetone. They include fats and fatty acids (saturated, which lack double bonds, and unsaturated, which contain double bonds). Their functions include:

• Energy storage (e.g., adipose tissue).
• Essential components of cell membranes.
• Thermal insulation.

Proteins

Proteins are the most important organic biomolecules. They are composed of amino acids. There are 20 types of amino acids, 13 of which are essential, meaning the body cannot manufacture them and must obtain them through diet. Their functions include:

• Structural: Building body tissues.
• Regulatory: Governing internal functions via hormones.
• Enzymatic: Acting as biocatalysts to accelerate chemical reactions.
• Nutritional: Serving as components of vitamins and enzymes.