Diversity of Living Things
Essay by kcalicia • July 20, 2016 • Exam • 4,210 Words (17 Pages) • 1,360 Views
Diversity of living things
Levels of Classification
-There are 8 levels of classification, called taxa. These are used to classify and organize all living things. These eight include:
- Domain
-Kingdom
-Phylum
-Class
-Order
-Family
-Genus
-Species
-Domain is the most inclusive level, then kingdom gets a little bit more exclusive as it goes down the taxa.
-using taxa, if two organisms are greatly related, they will have many taxa in common. Same goes if two organisms are vaguely related, they will have little taxa in common.
-Binomial nomenclature is the naming system for organisms. You use the Genus and species name, from the taxa of the organism, to name the organism. The genus name comes first, with the first letter of the name capitalized. Following is the species name, all letters lowercase. The final name (Genus species) is underlined, or italicized. (eg. Homo sapiens)
Cells
Eukaryotic (eg. Protists, Plants, Fungi, Animals) | Prokaryotic (eg. Bacteria, Archaea) | |
Structure | -DNA in nucleus bounded by membrane -Genome- Several chromosomes -mitosis and meiosis -multi-cellular (most) -sexual reproduction is most common | -DNA circular, not bounded by membrane -Genome- one chromosome -cell division binary fission -uni-cellular(most) -asexual production is most common -mitochondria and other membrane-bound are not present |
Size | -Large (100-1000um) | -Small (1-10um) |
Metabolism | -Most are aerobic | -most are anaerobic |
Bacteria
-3 main types (cocci, bacilli, and spirilla)
[pic 1]
-REPRODUCTION IN BACTERIA
-Binary fission(see def)[pic 2]
-Endospore formation(see def)
[pic 3]
-conjugation(see def)
[pic 4]
The six Kingdoms: COMPARED
Archea
Cell type- Prokaryotic
Structure- Unicellular
Resembles primitive clusters of molecules
Have cell walls and cell membranes, but are chemically different from Eubacteria
Metabolism- Autotrophic or heterotrophic
Reproduction- Asexual reproduction
Done by binary fission (see binary fission heading)
Habitat- Live in harsh enviroments
Divided into phyla based on habitat
Acidophiles- low pH environment
Thermophiles- temperatures>80 degrees
Halophiles- salt concentration up to 15%
Methanogens- oxygen-free
Nutrition- Photoautotroph (light, CO2)
Chemoautotroph (inorganic chemicals, CO2)
Photoheterotroph (light, organic chemicals)
Chemoheterotroph (organic chemicals, inorganic chemicals)
Eubacteria
Cell type- Prokaryotic
Structure- Unicellular
Cell wall structure depends on the arrangements of amino
acids in the cell walls
-Gram-positive
-Gram-negative
Round, rod-shaped or spiral
Found in pairs (di-), clusters (staphyio-), or chains (strepto-)
RNA- spirochaetes, chamydias, cyanobacteria, proteobacteria
Metabolism- Heterotropic or Autotropic
Reproduction- Binary fission
Habitat- Varied Aquatic or Terrestrial
Most common Bacteria
Nutrition- Photoautotroph (light, CO2)
Chemoautotroph (inorganic chemicals, CO2)
Photoheterotroph (light, organic chemicals)
Chemoheterotroph (organic chemicals, inorganic chemicals)
Protista
TYPES- animal-like, plant-like, fungi-like
Cell type- Eukaroytic,
Structure- Mainly unicellular
Metabolism- Autotrophic or heterotrophic
Reproduction- Unicellular protists reproduce by
Asexually- Binary Fission
Sexually- Conjunction
Multicellular protists have a more complex life cycle, which may involve alternation of generations where haploid egg/sperm produced is followed by diploid zygotes
Habitat- Mainly found in Aquatic or moist terrestrial
Nutrition- Heterotrophic or Autotrophic
Fungi
Cell type- Eukaroytic
Structure- Mainly Multicellular
Sessile
Cell walls composed of Chitin
Include basic structural units including
-Hyphae
-mycelium
-fruiting body
Metabolism- Heterotrophic
Reproduction- Mostly Asexual
Main three methods are:
Budding- small cell forms on parent cell
Fragmentation-small piece of mycelium breaks off
Spore production- production of small haploid cells
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