The oldest prokaryotic fossils have been dated to:
a. 1 billion years ago.
b. 2 billion years ago.
c. 4.6 billion years ago.
d. 3.5 billion years ago.
e. 2.5 billion years ago.
Ans: d. 3.5 billion years ago.
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True-breeding tall snapdragons with red flowers were crossed with short snapdragons with white flowers. The resulting F1 progeny were all of medium height and had pink flowers
When the F1 progeny are crossed with each other, what proportion of the F2 progeny would be of medium height and have pink flowers? A. 1/4 B. 1/2 C. 1/8 D. 1/16 E. 3/4
New England salt marshes experience a greater amount of plant growth in a given area in one year than any other temperate ecosystem. What characteristic do these salt marshes have?
A) low net primary productivity (NPP) B) high biodiversity C) high NPP D) an unlimited carrying capacity
Polygenic inheritance may result in a continuum of phenotypes because
A. the genes that are involved can be considered to be co-dominant B. the alleles for each gene are either completely dominant or recessive. C. there is a low environmental effect. D. there is a high environmental effect.
Choose the proper item below for statements 60–63
a. Thomas Brock b. Stanley Miller c. Jeon Kwang d. Lynn Margulis e. Australian researcher(s) M 60. He/she is a major proponent of endosymbiosis. E 61. He/she very early provided experimental evidence for endosymbiosis. D 62. He/she discovered an organism that contains a heatresistant enzyme. D 63. He/she conducted the first primitive atmosphere simulation experiment.