The Six Kingdom System
Biologists have accumulated a vast amount of information on Earth’s estimated 1.5 million species of organisms. Based on this information, taxonomists have developed various classification systems that group organisms according to their similarities. Fill in the table below by selecting terms from the following list: multicellular, unicellular, autotrophic, heterotrophic, prokaryotic, eukaryotic Autotroph: An organism that synthesizes food molecules from inorganic molecules by using an external energy source, such as light energy. Heterotroph: A microorganism which uses organic matter for energy and growth. Prokaryote: An organism or cell that lacks a membrane-bounded nucleus. Eukaryote: A cell or organism with a distinct membrane-bound nucleus as well as specialized membranebased organelles. Kingdom Archaebacteria
Number of cells Presence of membranebound nucleus Form of nutrition
1. If you were asked to classify an organism that is multicullular and autotrophic, in which two kingdoms might you place it? 2. If your “mystery organism” is unicellular and prokaryotic, into which two kingdoms might you place it? 3a. If the “mystery organism” is multicellular, eukaryotic, and, it could belong to which two kingdoms? 3b. What characteristics would help you determine in which kingdom it belonged?