Which of the following is considered the key innovation that started chordates along the evolutionary path that led to vertebrates?
A. An internal endoskeleton
B. A skin covering the entire body to prevent desiccation
C. An amniotic egg
D. A flexible rod to which muscles are attached, which allowed lateral movement of the back
E. A hard shell encasing the body
Answer: C
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Plants maintain higher levels of phytochrome at their growing tips where phytochrome plays important roles in growth responses to light. Phytochrome levels are also high in areas of the plant that are "greening". What does this suggest about the role of phytochrome in these "greening" zones?
A. Phytochrome is absorbing green wavelengths of light. B. In these areas, phytochrome is the first step in the electron transport chain of photosynthesis. C. Phytochrome is facilitating the transcription and translation of photosynthesis related proteins. D. Phytochrome is facilitating the migration of chlorophyll pigments from other areas of the plant. Clarify Question · What is the key concept addressed by the question? · What type of thinking is required? · What key words does the question contain and what do they mean? Gather Content · What do you already know about the role of phytochrome in plants? How does it relate to the question? Consider Possibilities · What other information is related to the question? Which information is most useful? Choose Answer · Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer? Reflect on Process · Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
What are the "highly specific molecular scissors" that cut DNA?
A) plasmids B) anticodons C) codons D) restriction enzymes
Symptoms of Toxic Shock Syndrome include all the following, except:
A. fever and muscle pain. B. appearance of flesh being "eaten" down to the muscle. C. nausea, vomiting, diarrhea. D. sunburn-like rash. E. kidney and liver failure.
What is the first step of DNA replication?
a. The DNA helix unwinds. b. The DNA polymerase adds nucleotides. c. RNA primers are removed. d. DNA fragments join ligase.