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Foundation of Biology
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In Biology, classification is the way to organize living things based on evolutionary relationships. Traditionally, we organize species into the standard hierarchy of kingdom, phylum, class, order, family and genus.
Cladistics is the method of classifying organisms into groups called clades. Clades consist of an ancestor organism and all of it's decedents and one branch is the tree of life. Cladograms are diagrams that show relationships within a clade.
A phylogenetic tree is a branching diagram that shows evolutionary relationships. These trees, often compared to family trees, are constructed using a variety of evidence generally using DNA. In phylogenetic trees, sometimes the lengths of the branches represent time since a group split from each other.
Like the Animal Kingdom, the Plant Kingdom is also a major part of the Linnaean system of classification that includes organisms like trees, bushes and grasses. The plants in this kingdom can be called autotrophs because they perform photosynthesis to provide food for themselves. These organisms also provide oxygen for humans and animals to survive.
Unlike the organisms of the Archaea or Monera Kingdoms, the Animal Kingdom consists of multi-cellular, heterotrophic organisms that feed on other organisms to survive. Some of the characteristics of the animals in this kingdom are being able to develop throughout their lives, move independently and reproducing.
The protist kingdom is a classification that includes a diverse group of eukaryotic organisms. Typically, protists reproduce asexually via mitosis and range from unicellular to multicellular organisms. In the protist kingdom, there are two main groups: protozoa (which are generally heterotrophic) and algae (which are generally autotrophic). Organisms in the protozoa group include things like amoebas, slime molds and paramecium while common organisms in the algae group include green algae, bro...
The Fungi Kingdom consists of plant-like organisms with small nuclei such as yeast, bread mold and mushrooms. Many of the organisms in the Fungi Kingdom can cause disease, but some are helpful as they are used to make things like antibiotics and yeast. Most of the organisms in this kingdom are parasitic and receive nutrients from surfaces they live on.
A virus is a nucleic acid encased in a protein shell and is inactive except within a host cell. Viruses penetrate host cells and inject their genetic information in the form of DNA or RNA. In the litic cycle, the virus uses the cell's functions to replicate its genetic information and create more viruses. In the lysogenic cycle, the virus leaves its genetic material dormant inside the cell as the cell reproduces until environmental conditions revive it and initiate the lytic cycle.
The Bacteria Kingdom, formerly called monera, are single celled prokaryotic organisms. Bacteria encompass two domains: eubacteria and archaea. Eubacteria and archaea have very different cell walls. They are also distinguished by their DNA - the DNA of archaea has histone proteins while that of eubacteria does not.
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