How do scientists calibrate a molecular clock for a group of organisms with known nucleotide sequences?
A) They use radioactive isotopes to measure the age of DNA material directly.
B) They graph the number of nucleotide differences against the dates of evolutionary branch points known from the fossil record.
C) They analyze fossilized DNA of known age and compare its nucleotide sequences to modern DNA sequences.
Answer: B
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The G + C content of a DNA sample can be estimated from its TM of a DNA.
Answer the following statement true (T) or false (F)
What gram-positive organisms are the smallest living cells?
a. actinomycetes b. halophiles c. prions d. mycoplasmas e. cyanobacteria
The equivalent in figure 2 of letter “D” in figure 1 is
indicated by a. E. b. F. c. G. d. H. e. all of these.
Which of the following describes the process of glycolysis?
a) It requires ATP and NADH. b) It represents the first stage in the chemical oxidation of glucose by a cell. c) Glycolysis produces 30 ATP from each molecule of glucose. d) Glycolysis occurs in the mitochondria. e) It converts one glucose molecule to two molecules of pyruvate and carbon dioxide