Biology 201 Unit 1

  1. Describe, in detail, the components and characteristics fo an experiment.
    • 1) A single independent variable: The IV is the component that is being manipulated by the scientist, it is what you are testing, the "cause" in "cause and effect."
    • 2) One or more dependent variable(s) which can be defined as the "effect" of "cause and effect," or as any change in initial conditions induced by the independent variable.
    • 3) One or more experimental (or test) group(s) in which the IV is included in the procedure.
    • 4) One or more control group(s), defined as a group that is treated the same as the experimental group, except the IV is withheld.
    • 5) Controlled Variables: factors that are common to both the experimental and control groups.
  2. You wish to determine whether a fertilizer actually improves the yield of corn in your vegetable garden, so you decide to do an experiment. 50 plants get fertilizer, 50 plants do not get fertilizer, and you weigh the ears of corn as your harvest. What is the IV, DV, experimental group, control group, controlled variables, and why the control group?
    • IV: Fertilizer
    • DV: Yield of corn
    • Exp Group: Plants WITH fertilizer
    • Control Group: Plants WITHOUT fertilizer
    • Controlled Variables: Temp, air exposure, etc.
    • Control group: To see whether or not the fertilizer truly increases the yield of corn
  3. What does it mean when scientists have a "95% confidence" in experimental results?
    That the difference between the experimental and control group is described as a "significant difference."
  4. What do scientists mean when they say there is a "significant difference" between two groups?
    It means that researchers have met the standard of "95% confidence" in experimental results.
  5. Describe the relationship between radioactive isotope half-lives and geologic time.
    The half-life of a radioactive isotope is the time it takes for a half of a sample of radioactive isotope to degrade into a non-radioactive isotope. The age of rock or fossils is computed based on the ratio of isotopes to their degradation series counterparts.
  6. What is the relationship between epochs, eras, periods, and eons?
    It is the geologic time scale which is broken into measures from longest measure of time to the shortest. (Eon, Era, Period, Epoch) They are of varying lengths (ie: One eon may be shorter than another) based on changes in the fossil or geologic record.
  7. Define Systematics
    The study of the diversity of life, both past and present, and the relationships of organisms through time.
  8. What factors are studied in systematics and used to establish evolutionary relationships between types of organisms?
    • 1) Genetic Analysis: DNA, RNA
    • 2) Morphology: Fine Anatomy, Gross Anatomy
    • 3) Biochemistry: Composition, Biochemical Pathways, Oxygen Toxicity
    • 4) Embryonic Development
    • 5) Life Cycles
    • 6) Ecological Roles
  9. Describe the relationship the following terms: Symbiosis, commensalism, mutualism, parasitism, definitive host, intermediate host, ectoparasite, endoparasite, and accidental host.
    • 1) Symbiosis: long term interaction between different biological species
    • 2) Commensalism: one species benefits, one is neutral
    • 3) Mutualism: both benefit
    • 4) Parasitism: one benefits, one is harmed
    • 5) Parasite: doing damaged; Host: being damaged
    • 6) Ecto: outside body, Endo: inside body
    • 7) Intermediate Host: not sexually mature to the parasite
    • 8) Definitive Host: sexually mature; adult
    • 9) Accidental Host: not typical/normal
  10. List the basic Linnean taxons in the proper order.
    Kingdom, Phylum, Class, Order, Family, Genus, Species
  11. How are scientific names derived?
    First inital of Genus and then Species. Underlined or italicized.
  12. Was taxonomy, as devised by Linneaus, phylogenetic?
    Not according to Linneaus.
  13. Describe the relationship between the following: monophyletic, paraphyletic, polyphyletic clades; phylogenetics, clade, cladogram.
    • 1) Monophyletic: Same common ancestor
    • 2) Paraphyletic: Missed but should be included. When a clade is incomplete.
    • 3) Polyphyletic: When a clade combines organisms from different lineages.
    • 4) Phylogenetics: approach to classification in which those with the most recent common ancestor are considered most closely related.
    • 5) Clade: A group of organisms, such as a species, whose members share homologous features derived from a common ancestor.
    • 6) Cladogram: A branching, treelike diagram in which the endpoints of the branches represent specific species of organisms.
    • It is used to illustrate phylogenetic relationships and show points at which various species have diverged from common ancestral forms.
  14. Describe traditional vs. cladistic approaches to classification - which is the favored approach?
    The traditional approach focuses more on how two species look like. The cladistic approach focuses on the ancestral and derived characteristics. The favored approached is the modern/cladistic approach.
  15. Describe the domains of life and each's characteristics.
    Eubacteria: unique cell walls, mRNA's code for multiple proteins

    Archaea: unique plasma membranes

    Eukarya: eukaryotic (true nucleus), typically much larger, membranous organelles
  16. What is the evolutionary relationship between the three domains?
    Between Eubacteria and Archaea -- Both prokaryotic, small, operons
  17. What is the justification for the three Domains, why not lump the Archaea and Eubacteria together?
    Archaea shares traits with both Eubacteria and Eukarya. And through evolved time, Archaea and Eukarya have more characteristics in common than Archaea and Eubacteria.
  18. What is the purpose of a gram stain?
    To distinguish bacteria biochemically begins with cell wall composition and the stains they bind. It detects the presence of a particular type of cell wall.
  19. Obligate Aerobes
    Require oxygen; their energy pathways are oxygen dependent
  20. Obligate Anaerobes
    They are oxygen sensitive and have only fermentation (anaerobic) energy pathways. Can't have oxygen.
  21. Facultative Anaerobes
    Can tolerate oxygen, but not obliged. Thrive in either aerobic or anaerobic.
  22. Facultative Heterotroph
    Can make their own food but does not have too. Can also get food/energy from other inorganic sources.
  23. Photoautotrophs
    Use solar energy to construct organic molecules.
  24. Chemoautotrophs
    Use energy from exergonic inorganic chemical reactions to supply the energy to construct organic molecules.
  25. Obligate Heterotrophs
    Must consume organic molecules, they cannot make their own from inorganic sources.
  26. Autotrophs
    Creates their own organic molecules.
  27. Describe factors considered in prokaryotic classification.
    • 1) Genetic Analysis: DNA, RNA
    • 2) Morphology: Fine and Gross Anatomy
    • 3) Biochemistry: Composition, Biochemical pathways, Oxygen Toxicity
    • 4) Embryonic Development
    • 5) Life Cycles
    • 6) Ecological Roles
Card Set
Biology 201 Unit 1
Unit 1 Study Guide