For approximately how long was Earth populated exclusively by microscopic organisms?
a. 2 billion years
b. 500 million years
c. 750 million years
d. 3 billion years
e. 4 billion years
Answer: d. 3 billion years
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Modern cells are thought to have arisen from ____
a. protocells b. pre-cells c. gas and dust clouds d. prokaryotic cells that predated protocells e. prokaryotic cells that predated pre-cells
In prophase I of spermatogenesis, there are ____ chromatids
a. 23 b. 46 c. 69 d. 92 e. 115
You are given an unknown organism to identify. It is unicellular and heterotrophic. It is motile, using many short extensions of the cytoplasm, each featuring the 9 + 2 filament pattern
It has well-developed organelles and two nuclei, one large and one small. This organism is most likely to be a _____. A) foraminiferan B) radiolarian C) ciliate D) kinetoplastid
You are playing a computer game for which you must create creatures to survive in particular environments. You species is sessile with a low chance of encountering a mate. The environment it lives in is unpredictable. The BEST mode of reproduction you could choose for your species would be:
What will be an ideal response?