Cells, Biomolecules, and Cellular Transport

Cellular Classifications and Types

  • Prokaryotic cells:
    • Do not contain a nucleus.
    • Are not bound by a cell wall.
    • Representative examples include coccus, bacillus, and sporelium.
  • Eukaryotic cells:
    • Contain a nucleus that is bound by a cell membrane.
    • Representative examples include plant and animal cells.

Principles of Modern Cell Theory

  • DNA transmission:
    • DNA is passed between cells during the process of cell division.
  • Molecular and structural uniformity:
    • Cells and DNA of similar organisms possess similar chemistry and structure.
  • Energy dynamics:
    • Energy flows continuously within cells.
  • Origin of life and cellular generation:
    • Clothing organisms cells life.
    • Cells arise strictly from pre-existing cells.

Organelles and Cellular Structures

  • Nucleus:
    • Contains DNA that governs and controls the unique characteristics of the cell.
    • Responsible for producing ribosomes.
  • Protective barrier (Cell membrane):
    • Functions as a selective protective barrier.
    • Regulates and controls all substances that enter and leave the cell.
  • Mitochondria:
    • Defined as the powerhouse of the cell.
    • Serves as the cell's main source of energy.
  • Vacuole:
    • Acts as a storage organelle designated for storing nutrients and waste.
  • Endoplasmic reticulum:
    • Employs ribosomes to synthesize and make protein.
  • Lysosome:
    • Contains digestive enzymes specifically dedicated to breaking down waste materials.

Macromolecules, Monomers, and Polymers

  • Carbohydrates:
    • Chemical composition is made of carbon.
    • Functions as the main source of energy for living organisms.
    • Monomer: Monosaccharide.
    • Polymer: Carbohydrate.
  • Lipids:
    • Insoluble biomolecules that do not dissolve in water.
    • Utilized by cells to store energy, construct cellular membranes, and nucleic acids.
    • Monomer: Fatty acids.
    • Polymer: Lipids.
  • Nucleic acids:
    • Monomer: Nucleotide.
    • Polymer: Nucleic acid.
  • Proteins:
    • Monomer: Distinct group of 20 amino acids.
    • Polymer: Proteins and three e.

Nutritional and Trophic Classifications

  • Autotrophic organisms:
    • Characterized by the ability to produce their own nutrients internally.
  • Heterotrophic organisms:
    • Characterized as organisms that must ingest or absorb nutrients from outside sources.

Cellular Transport Mechanisms

  • Passive energy-free transport:
    • Transport type requiring no energy input.
    • Involves the spontaneous movement of substances from high condition to low condition ("this just happens").
    • Encompasses osmosis and diffusion involving particles, including particles that dissolve.
  • Endocytosis:
    • The general process of substances entering the cell.
    • Moves items such as thermometer and spruces into the cellular interior.
    • Facilitates small particle transport.
    • Phagocytosis:
    • Process characterized as "eating a cell."
    • Responsible for internalizing and taking in large particles.
    • Penocytosis:
    • Process characterized as "drinking a cell."
    • Responsible for internalizing and taking in extracellular food.
    • Receptor-mediated transport:
    • Involves the ingest of a specific cell target.
    • Functions mechanically like a "lock on heat."
  • Exocytosis:
    • The physiological process of eliminating or removing substances and cellular waste from the cell.
    • Involves cellular fluid exiting the cell.