Lecture Notes-05 Biology 1004

North Arkansas College

Topic: Classification

  1. Levels of Organization

  2. Five Kingdoms of Characteristics

  3. Classification of Humans

  4. Three Domains of Living Organisms

  5. Latin Binomial System of Naming Organisms

  6. Phylogeny and Characteristics

Levels of Organization
  1. Kingdom
  2. Phylum or Division
  3. Class
  4. Order
  5. Family
  6. Genus
  7. Species

Five Kingdom System of Classification

Roger Whitaker proposed five-kingdom system in 1968.
  1. Animalae; Exhibit movement, ingest nutrients, multicellular, Eucaryotic, no cell wall, no photosynthesis.
  2. Plantae; make their own nutrients, intracellular cytoplasmic movement occurs, photosynthesis, Eucaryotic, most are multicellular, have cell wall, reproduce sexually by forming gametes, surface of leaves is covered by waxy substance to prevent dehydrations (cuticle), small openings in leaf for gas exchange (called stomata), includes non-vascular plants (masses) and vascular plants (conifers, etc.).
  3. Protista; Eucaryotic (well defined nucleus), single and multicellular, asexual/sexual reproduction, algae, protozoa.
  4. Fungi; Eucaryotic, absorb nutrients after decomposing organic matter, made up of long filaments of cells called hyphae which form masses to make mycelium, yeast, molds to mushrooms.
  5. Procaryotes; No well defined nucleus, unicellular, bacteria, blue green bacteria (cyanobacteria).

* Viruses; Do not fit in this classification. They are non-cellular. Some argue as to whether they are alive or not.

Classification of Humans
  1. Kingdom: Animalae; Usually motile movement, no cell wall; usually have internal cavity for ingestion.
  2. Phylum: Chordata; At some time they contained a central spinal column and pharyngeal pouches.
  3. Class: Mammalia; Warm blooded, body covered with hair, mammary glands, developed brain.
  4. Order: Primates; Opposing thumbs and sometimes big toes, good brain development, lacking claws, scales, horns and hoofs, bipedal locomotion.
  5. Genus: Homosapien; Stand upright, bipedal motion.

Three Domains

Proposed in 1978 by Carl Woese. Domain is higher than kingdom. It is based on common ancestor.
  1. Eucaryotes; All higher organisms (Protist, Fungi, Plants and Animals).
  2. Eubacteria; True bacteria.
  3. Archaebacteria; Ancient bacteria. These are significantly different from Eubacteria and other life forms. They are found around thermal vents. They are similar to fossils found in meteorites found in Greenland and Australia. They have less than 40% homology with DNA from any other known species. They possess some characteristics of Procaryotes, and some characteristics of Eucaryotes, and some of neither. There is speculation that they actually came to Earth from Mars with meteorites. They may be common ancestor.

Latin Binomial System of Naming Organisms

Developed by Carl Linne’. Use Genus (Capitalized Letters), species (Small Letters), set off in italics or bold type.
  1. Canis familaris; dog
  2. Canis lupus; wolf
  3. Felis domesticus; cat
  4. Quercus albus; American white oak
  5. Quercus ruburum; English white oak
  6. Homo sapiens; humans

Phylogeny or Phylogenic Inheritance

Classification scheme based on common ancestry. Arranged as a classification tree; branches correspond to newer species; trunk corresponds to original species; and roots are common ancestry.

Cladistics

Degree of relatedness.

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