Biomolecules

Introduction to Biomolecules

Biomolecules are the chemicals found in living organisms and are essential for life. They form the molecular components of all organisms and are involved in structure, function, and regulation of the body's tissues and organs.

• Definition: Biomolecules are organic molecules produced by living organisms.

• Main Classes: The four major classes of biomolecules are carbohydrates, nucleic acids, proteins, and lipids.

• Importance: These molecules are involved in energy storage, genetic information, catalysis of biochemical reactions, and formation of cellular structures.

Building Blocks of Molecules

Matter and Elements

All living and non-living things are made up of matter. Matter is anything that occupies space and has mass. The fundamental units of matter are elements, which cannot be broken down chemically into other substances.

• Element: A pure substance consisting of only one type of atom, each with constant and unique properties.

• Atoms: The smallest unit of an element that retains the chemical properties of that element.

• Number of Elements: There are 118 known elements, but only about 92 occur naturally. Fewer than 30 elements are commonly found in living organisms.

• Unstable Elements: Some elements are unstable (radioactive) or theoretical and have not been detected in nature.

Atomic Structure

Atoms are composed of subatomic particles: protons, neutrons, and electrons. The arrangement and number of these particles determine the properties of each element.

• Proton: A positively charged particle located in the nucleus of an atom.

• Neutron: An uncharged (neutral) particle also found in the nucleus.

• Electron: A negatively charged particle that orbits the nucleus in electron shells.

• Element Identity: The number of protons (atomic number) defines the type of element.

• Isotopes: Atoms of the same element with different numbers of neutrons, affecting physical stability.

• Chemical Properties: Determined by the number and arrangement of electrons, especially those in the outermost shell (valence electrons).

Example: Carbon has 6 protons, 6 neutrons (in its most common isotope), and 6 electrons. Its atomic number is 6.

Summary Table: Subatomic Particles

Additional info: The arrangement of electrons in shells (energy levels) follows the 2n2 rule, where n is the shell number. The outermost shell determines the atom's chemical behavior.