The endoskeleton of an echinoderm is composed of
A) cellulose.
B) silica.
C) calcium carbonate.
D) chitin.
E) lignan.
C
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Under the "business as usual" model of climate change, will temperatures change uniformly across the globe?
Examine Figure 48.7 in your text and compare the projected change in temperature in central South America and central Africa at the equator (draw an imaginary line across the globe at its widest point and examine a spot in the middle of each continent along that line). Which of the following best describes the predicted changes? A. Central South America will warm by an average of 7–8 degrees; central Africa will warm by around 3–4 degrees. B. Central South America will warm by an average of more than 8 degrees; central Africa will warm by 1–2 degrees. C. Central South America will remain about the same; central Africa will warm by 7–8 degrees. D. Central South America will warm by 2–3 degrees; central Africa will not change. E. Both central South America and central Africa will warm by 4–5 degrees.
What is the map distance between two genes with a recombination frequency of 0.08?
A: 0.08 cM B: More information is required to answer this question. C: 0.8 cM D: 8 cM E: 80 cM
During DNA replication, which of the following enzymes separates the DNA strands during replication?
A. DNA polymerase III B. ligase C. DNA polymerase I D. helicase
The degeneration of nuclei is occurring in step(s)
a. 4. b. 5. c. 8. d. 4 and 5. e. 4 and 8.