Ch. 22

  1. There are four stages that we know for sure about the begings of life. What are the four stages?
    1. Nucleotides and amino acids produced. 2.Mucleotides and aminos polymerized to make RNA and proteins. 3. Polymers became enclosed in a membrane. 4.They them aquired cellular properties.
  2. Slow accumulations of molecules in the ocean into organic molecules is calle what?
    Probiotis soup.
  3. Based largely on geological data, h2 methane and ammonia and water vapor existed and then the formation of hydrogen cyanide (HCN) and formaldehyde (CH2O). Such molecules are precursors of more complex organic molecules. These precursors also combined to make larger molecules such as the amino acid glycine. At the end of 1 week of operation, 10–15% of the carbon had been incorporated into organic compounds
    Reducing atmosphere hypothesis.
  4. Theory that organic molecules where placed here or where carried on a commet or merteroite.
    Extraterrestrial hypothesis
  5. key organic molecules may have originated in deep-sea vents, which are cracks in the Earth’s surface where superheated water rich in metal ions and hydrogen sulfide (H2S) mixes abruptly with cold seawater. These vents release hot gaseous substances from the interior of the earth at temperatures in excess of 300°C
    Deep-seas vents
  6. Organic polymer may have been formed on the surface of?
  7. cell-like structuresmay have originated when polymers were enclosed by a?
  8. An aggregate of prebiotically produced molecules and macromolecules that acuquired a boundry.
  9. What are the four key features that make probiotics possible precursors to living cells?
    1. Boundry seperates the internal from external environment. 2. Polymers inside contain information. 3. polymers inside had ezymatic functions. 4. Probionts eventually developed the capability of self-replication.
  10. Cells could have evolved from droplets that form spontaneously from the association of charged polymers such as proteins, carboydrates, or nucleic acids surrounded by water
  11. The second possibility is that probionts evolved from vesicles surrounded by a lipid bylayer known as?
  12. What are the 3 key functions of RNA?
    Store Info, capcity for self replication, and perform ezyme like functions.
  13. Occurs when a chemical within a mixture has special properties or advantages that cause it to increase in number compared to other chemicals in the mixture.
    Chemical Selection. Possible reason RNA came to be.
  14. is a hypothetical period on early Earth when both the information needed for life and the enzymatic activity of living cells were contained solely in RNA molecules
    RNA world
  15. These are made up of a combination of the 20 amino acids.
  16. Are the preserved remains of past life on earth
  17. Scientists that study fossils are called?
  18. What kind of rock are fossils preserved in?
    Sedimentary rock
  19. A common way to estimate the age of a fossil is by analyzing the decay of radioisotopes within the accompanying rock, a process called
    Radioisotope dating
  20. is the length of time required for a radioisotope to decay to exactly one-half of its initial quantity.
  21. What are some reasons that fossils are biased?
    Size, some are more likely to be, shells and bones, number, and environment.
  22. is a time line of the Earth’s history and major events from its origin approximately 4.55 billion years ago to the present
    Geological time scale
  23. The names of several eons and eras end in -zoic meaning
    animal life
  24. the complete loss of a species or group of species
  25. What where the major environmental changes?
    Climate/Temperature, Atmosphere, Landmasses, Floods/glaciation, Volcanic eruptions, and meteorite impacts
  26. The shift of landmasses.
    Continental drift
  27. many species to go extinct at the same time
    mass extinction
  28. These cells arose during the archean eon
    Prokaryotic cells
  29. Organisms may follow two different strategies to obtain energy; what are they?
    heterotrophs, and autotrophs.
  30. their energy is derived from the chemical bonds within organic molecules they consume
  31. directly harness energy from either inorganic molecules or light.
  32. These layers are mats of mineralized cyanobacteria, one layer on top of the other
  33. relationship is one in which two different species live in direct contact with each other
  34. relationship, in which a smaller organism (the symbiont) lives inside a larger organism (the host)
  35. The first animals where
  36. This era had a warm and wet climate, no evidence of ice. rapid diversity of species called () explosion. Also, mainly shelled animals
    Cambrian period
  37. The first vertebrates showed up how long ago?
    520 mill
  38. Climate was warm and moist. marine invertbrates. First plants started to show
    Ordovician Period
  39. Stable, high ocean levels, new fishes, and vascular plants.
    Silurian period.
  40. Dry climate, seed plants, tetrapods started showing up.
    Devonian period
  41. Coal deposits, Large plants and trees, first flying insects, emmurgence of reptiles.
    Carboniferous period.
  42. This was where Pangea started. fernlike plants replaced by gymnosperms (modern conifers). Largest known mass extinction.
    Permain Period
  43. Reptiles plentiful and dinos, and first true mammals.
    Triassic period.
  44. Gymnosperns, mammals not prelvant. Reptiles dominant. Manin dinos.
    Jurassic period.
  45. This period had flowering plants, dinos, mass extinction of dinos.\
    Cretatious period
  46. This period is where hominoids showed up.
  47. refers to a subset of hominoids, including modern humans, extinct human species (for example, of the Homo genus), and our immediate ancestors
  48. Ice ages, hominins became more human like, 1.8-today
    quaternary period
Card Set
Ch. 22
Exam 1 set