Levels of Biological Organization: Bioelements & Biomolecules

Levels of Biological Organization

Subatomic Level: Includes subatomic particles that make up atoms (electrons, protons).

Atomic Level: Includes atoms that constitute our body. A bioelement is the set of atoms of the same type.

Molecular Level: Includes molecules and clusters of molecules, such as the cell membrane, composed of various types of cellular molecules.

Cellular Level: Includes cells and multicellular organelles.

Tissue Level: The level of organization of multicellular individuals, including tissues (structures formed by cells), the bodies, devices, and systems (set of organs).

Population Level: Comprises groups of individuals living in the same area at a specific time.

Ecosystem Level: Includes the set of relationships that exist between people and the environment.

Bioelements and Biomolecules

Bioelements: Are the elements that constitute living matter.

  • Primary: 96% are (C) (O) (H) (N) (Sulfur) (P)
  • Secondary: All other elements.

Biomolecules: Are the molecules that constitute living matter.

  • Organic: Are those formed by C and H (carbohydrates, lipids, nucleic acids, proteins)
  • Inorganic: Not consisting of C and H (water and mineral salts)

Cellular Structures and Their Functions

Rough Endoplasmic Reticulum: Flat sacs that originate bound to the nuclear envelope and extend throughout the cytoplasm. Characterized by having many ribosomes attached. Function: stores and transports proteins synthesized by its ribosomes.

Smooth Endoplasmic Reticulum: Similar in form but with tubules that extend throughout the cytoplasm. No ribosomes are present. Function: synthesizes lipids and stores them, distributing them, along with proteins from the rough endoplasmic reticulum, throughout the cell.

Ribosomes: Structures formed by two globular subunits without a membrane that synthesize protein molecules.

Vacuoles: Membranous organelles, generally globular in shape, in which various kinds of substances are stored: water, nutrients, waste products, etc.

Golgi Apparatus: Membranous organelle made up of a series of flattened, disc-shaped sacs. Produces and receives and transports substances from the endoplasmic reticulum.

Lysosomes: Small vesicles originating from the Golgi apparatus containing digestive enzymes. Involved in the digestion of materials the cell ingests.

Mitochondria: Cylindrical organelles comprised of a double membrane, a smooth outer membrane, and an inner membrane with numerous folds. Function: performs cellular respiration.

Centrosome: Two cylindrical structures consisting of tubules.