Which of the following gases was the least abundant in the earth's atmosphere 3.5 billion years ago?
a. carbon dioxide
b. oxygen
c. water vapor
d. hydrogen
e. nitrogen
Ans: b. oxygen
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The two major divisions of the vertebrate
nervous system are the a. autonomic and peripheral systems. b. sympathetic and parasympathetic systems. c. cranial and spinal nerves. d. central and peripheral nervous systems. e. brain and spinal cord
The major product of the Calvin Cycle is
a. rubisco b. oxaloacetate c. RuBP d. pyruvate e. glyceraldehyde - 3- phosphate
Which of the following should prevent a grass seedling shoot from bending toward light?
a. removing the shoot tip b. placing a translucent cap on the shoot tip c. placing an opaque cap on the shoot tip d. either removing the shoot tip or placing a translucent cap on the shoot tip e. either removing the shoot tip or placing an opaque cap on the shoot tip
Fossils are the remains and traces of past life that have been preserved in the Earth's crust. What type of fossils is most important in supporting the principle of evolution? Explain your answer and give examples.
What will be an ideal response?