The oxygen in the atmosphere developed approximately ________ billion years ago.
A. 4.5
B. 2.0
C. 3.5
D. 1.5
Answer: B
Biology & Microbiology
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Trophic pyramids typically have a ____ base and a ____ top portion
a. narrow; narrow b. narrow; wide c. wide; narrow d. wide; wide e. flat; flat
Biology & Microbiology
HIV is transmitted in ____
a. food b. water c. body fluids d. air e. infected surfaces
Biology & Microbiology
What type of eating disorder involves consuming large amounts of food, followed by self-induced vomiting?
A) anorexia B) bulimia C) osteoporosis D) diabetes
Biology & Microbiology
The mitochondria of a eukaryotic cell is the site of
a. photosynthesis b. fatty acid metabolism c. cellular respiration d. protein synthesis
Biology & Microbiology