It is thought that the first cells probably arose about _____ years ago.
A. 1.2 billion
B. 2 billion
C. 500 million
D. 3.5 billion
E. 6 billion
D. 3.5 billion
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Temperature changes can affect the ability of water to dissolve and keep materials in solution. Which statement below is an appropriate hypothesis concerning water temperature and dissolved oxygen?
A) Lower water temperatures allow for lower concentrations of dissolved oxygen. B) Higher water temperatures allow for higher concentrations of dissolved oxygen. C) Lower water temperatures allow for higher concentrations of dissolved oxygen. D) Water temperatures do not affect the concentration of dissolved oxygen
The human retina has several layers of cells/tissues in the eye. What is the order of appearance of these cells from the front (where light hits first) to the back of the eye?
A. rods and cones; bipolar cells; pigmented epithelium; ganglion cells B. ganglion cells; bipolar cells; rods and cones; pigmented epithelium C. rods and cones; ganglion cells; bipolar cells; pigmented epithelium D. pigmented epithelium; rods and cones; ganglion cells; bipolar cells
A defining characteristic that distinguishes prokaryotic and eukaryotic organisms is the lack of a cell membrane in prokaryotes.
Answer the following statement true (T) or false (F)
Which of the following is an example of how cultural change influences evolution?
A. Africans being carriers for sickle trait in areas where malaria is present B. Inuits in Greenland having a larger body, reducing surface area to volume C. people in the northern regions having less pigmentation in order to obtain more vitamin D D. people becoming lactose tolerant in areas where the domestication of cattle occurred