The geologic time scale is often subdivided on the basis of ____.
A. the appearance of different radioactive isotopes in different strata
B. levels of background extinction
C. periods of extensive environmental change
D. the appearance of new species
E. climate change
Answer: C
You might also like to view...
Which of the following suggested a method of DNA replication to Watson and Crick?
A. The backbone of the DNA helix is antiparallel. B. Due to complementary basepairing, each strand could act as a template for the other. C. The DNA helix has a major and a minor groove. D. The two strands are held together by strong, covalent bonds. E. The DNA helix is stabilized by hydrophobic stacking.
Which medium can be described as containing hemoglobin, hemin (X factor), and the co-enzyme nicotinamide adenine dinucleotide (NAD) (V factor)?
a. Chocolate b. CNA blood c. BHI d. Thioglycollate broth
What evolutionary advantage do prokaryotes have over eukaryotes?
What will be an ideal response?
In the process of diffusion, molecules move from areas where
A. their concentration is higher to areas where their concentration is lower using energy from ATP. B. their concentration is lower to areas where their concentration is higher through specific protein channels or carriers. C. their concentration is lower to areas where their concentration is higher until an equilibrium is reached. D. their concentration is higher to areas where their concentration is lower until an equilibrium is reached.