1 | Cells: the fundamental units of life

  • Archaeon: One of the two divisions of prokaryotes, often found in hostile environments such as hot springs or concentrated brine 

  • Bacterium: One of the two divisions of prokaryotes. Some species cause disease. 

  • Cell: The basic unit from which a living organism is made

  • Chloroplast: Specialized organelle in algae and plants that contains chlorophyll and serves as site in which photosynthesis takes place 

  • Chromosome: Long, threadlike structures consist of DNA and proteins that carry the genetic information of an organism. Becomes visible and as a distinct entity when a plant or animal cell prepares to divide 

  • Cytoplasm: Contents of a cell that are contained within its plasma membrane - but, in the case of eukaryotes, outside the nucleus 

  • Cytoskeleton: System of protein filaments in the cytoplasm of a eukaryotic cell that gives the cell shape and the capacity for directed movement. Actin filaments, microtubules, and intermediate filaments 

  • Cytosol: Contents of the main compartment of the cytoplasm, excluding the membrane enclosed organelles. What remains after the membranes, cytoskeletal components and other organelles have been removed 

  • DNA: Double stranded polynucleotide formed from two separate chains of covalently linked deoxyribonucleotide units . serves as the cell's source of genetic information that is transmitted from generation to generation 

  • Electron microscope: Instrument that illuminates a specimens using beams of electrons to reveal and magnify the structures or very small objects, such as organelles and large molecules 

  • Eukaryote: An organism whose cells have a nucleus and cytoplasm 

  • Evolution: Process of which gradual modification and adaptation that occurs in living organisms over generations 

  • Fluorescence microscope: Instrument used to visualize a specimen that has been labeled with fluorescent dye. Samples are illuminated with a wavelength of light that excites the dye, causing it to fluoresce.

  • Genome: The total genetic information carried by all the chromosomes of a cell or organism 

  • Homologous: Possessing identical alleles for a given gene 

  • Micrometer: Unit of length equal to one millionth of a meter 

  • Microscope: Instrument for viewing extremely small objects

  • Mitochondrion: Membrane-enclosed organelles, that carries out cell respiration

  • Model organism: A living thing selected for intensive study as a representative of a large group of species 

  • Nucleus: The prominent, rounded structure that contains the DNA of a eukaryotic cell 

  • Organelle: A discrete structure or subcompartment of a eukaryotic cell that is specialized to carry out a particular function 

  • Photosynthesis: The process by which plants, algae and some bacteria use the energy of light to drive the synthesis of organic molecules from carbon dioxide and water 

  • Plasma membrane: The protein-containing lipid bilayer that surrounds a living cell 

  • Prokaryote: Living cells without a nucleus 

  • Protein: Polymer built from amino acids. Provide cells with their shape and structure, and performs most of their activities

  • Protozoan: A free-living, nonphotosynthetic, single-celled, motile eukaryotic 

  • Ribosome: Large macromolecular complex, composed of ribosomal RNAs and ribosomal proteins, that translates messenger RNA into proteins 

  • RNA: Molecules produced by the transcription of DNA. single stranded. Composed of covalently linked ribonucleotide subunits.