DAT Diversity of Life Flashcards
(120 cards)
Independent metabolism
viruses lack this and so are not considered truly ‘alive’
Ability to self-replicate
this determination does not include the ability to produce gametes!
How many main criteria in determining the living vs the non living
2
The taxonomic ranks, from most general to most specific, are
domain, kingdom, phylum, class, order, family, genus, species.
Way to remember the taxonomic levels…
King Philip came over for grape soda
Systematics
The study of evolutionary relationships among organisms.
Prokaryotic cells have a..
single chromosome that is short. They have circular DNA that usually does not have histones.
The flagella of prokaryotes consist of
chains of the protein flagellin
Autotrophs
manufacture their own organic materials. They use light (photo) or chemicals (chemo) such as H2S, NH3, NO, and NO3
Heterotrophs
obtain energy by consuming organic substances produced by autotrophs
Parasites
obtain energy from living
tissues of hosts
Saprobes (saprophytes)
obtain
energy and feed from dead, decaying matter which contribute to organic decay. Decomposers are slightly different in that they break down dead and decaying matter
Obligate aerobes
must have O2 to live
Obligate anaerobes
require the
absence of O2 to live; they cannot live with the presence of oxygen. They are unable to detoxify some products of oxygen metabolism (e.g., H2O2 would be toxic to them)
Facultative anaerobe
grows in the presence of O2, but can switch to anaerobic metabolism when O2 is absent
Archaea
prokaryotes but they differ from bacteria. Archaea are non-pathogenic.Archaeal cell walls contain various polysaccharides,
Similarities between eukaryotes and archaea
- DNA of both archaea and eukaryotes
are associated with histones, while
bacterial DNA is not - Ribosome activity is not inhibited by
antibiotics streptomycin and chloramphenicol, unlike bacteria
Methanogens
Group of archaea: obligate anaerobes that
produce CH4 as a by-product of obtaining energy from H2 to fix CO2
Extremophiles
Group of archaea: live in extreme enviroments
Halophiles (salt lover)
Group of extremophiles: they live in high salt concentration environments. Most are aerobic and heterotrophic; others are anaerobic and photosynthetic with bacteriorhodopsin
Thermophiles (heat lover
Group of extremophile:are sulfur-based chemoautotrophs that live in very hot places
Other extremophiles
live in high acid/base/pressure environments
Domain Bacteria
Bacteria are distinct from archaea and eukaryotes because of certain features. Bacteria have cell walls that have peptidoglycan, which is a polymer of monosaccharides with amino acids. Bacterial DNA is not associated with histones, and ribosome activity is inhibited by antibiotics like streptomycin and chloramphenicol.
Classification of bacteria
- Mode of nutrition/how they metabolize resources
- Ability to produce endospores 3. Means of motility 4. Shapes 5. peptidoglycan cell wall