The immediate principles or biomolecules

If a physical analysis of living matter is carried out, so that we can separate each of the substances that compose it without them being altered, we arrive at the so-called immediate principles or biomolecules. The methods used for this analysis are evaporation, filtration, distillation, dialysis , crystallization, electrophoresis, and centrifugation.

The immediate principles can be:

• Simple: when the molecules are made up of atoms of the same chemical element, as in the case of oxygen (O ₂ ) and nitrogen (N₂).
  • O₂ is necessary for aerobic respiration in aerobic bacteria and in the mitochondria of animal and plant cells .
  • N₂ is practically an inert gas, so plants cannot capture it from the atmosphere . Only some bacteria in the soil and others, which are symbionts of the roots of legumes, are capable of capturing it and taking advantage of it to synthesize proteins .
• Compounds: when molecules are made up of atoms of different elements, such as water (H ₂ O). Compound immediate principles can be:
  • • Inorganic. For example, water, mineral salts (carbonates, phosphates, etc.) and carbon dioxide (CO₂).
    • Organic Made up mainly of carbon and hydrogen , such as carbohydrates , lipids , proteins, and nucleic acids .

via Gfycat

The immediate principles may have different functions:

• Structural function, such as proteins and mineral salts in bones, or lipids in plasma membranes.
• Energy function, such as lipids.
• Biocatalyst function, that is, accelerator of biochemical reactions, such as enzymatic proteins.

The water and mineral salts are discussed below , as well as the properties of true solutions and colloidal dispersions. Carbohydrates, lipids, proteins, and nucleic acids are covered in the following topics.