1. According to current theories about the origin of life, which oneof the following must have preceded all the others?
     
eukaryotic organisms.
oxygen in theatmosphere.
photosynthesis.
plants.

2. If the first organisms on Earth were heterotrophs they wouldhave

eatenautotrophs.
required organicmolecules in their environment.
carried onphotosynthesis.
used RNA as their geneticmaterial.

3. Algae are in the kingdom

Plantae.
Mycetae.
Protista.
Animalia.

4. An examination of the fossil record of life on Earth reveals that

extinctions rarelyaffected more than 10-20% of existing species.
terrestrial organismswere less likely to go extinct than marine organisms.
it usually took 100s ofmillions of years for new organisms to appear.
None of the above istrue.

5. Viruses differ from Eubacteria in that viruses

have a nucleus andEubacteria lack a nucleus
lack genetic material.
are larger thanEubacteria.
can only reproduce insideanother cell

6. effect of water temperature on a fish in a stream wouldbe classified as a (an)

bioticfactor.
abioticfactor.
niche.
None of theabove.