About a billion years ago, the first complex cell is thought to have evolved by the fusion of two
cells. This is the Endosymbiotic Theory and two organelles found in eukaryotes to support this
theory of evolution are chloroplasts and mitochondria. What was thought to be the host cell?
a. Nucleus
b. Cell membrane
C. Protista
d. Archaea bacterium.

The many stone tools, fragmentary animal bones, and teeth found at gran dolina, spain, indicate that hominids there? a. processed and consumed animals and other hominids. b. did not differ appreciably from earlier asian homo erectus. c. were similar to later homo sapiens. d. none of the above

Where is most of the fresh water on earth found a in the ocean b in glaciers and in ice caps c in rivers d in the soil

Cells a and b are the same size and shape, but cell a is metabolically quiet and cell b is actively consuming oxygen. oxygen will diffuse more quickly into cell because . b the oxygen molecules inside cell b have a higher kinetic energy b. a its membrane transport proteins will not be saturated c. a the diffusion gradient there is shallowerd. b the diffusion gradient there is steeper