Which of the following statements about hormones initiating second messenger systems is (are) true?
a) A lipophilic hormone initiates the system by binding to a receptor on the cell membrane
b) A single hormone molecule binding to a receptor can ultimately activate millions of proteins
c) A G protein is considered to be the second messenger
d) Both a and b are true
e) Both b and c are true
Answer: b) A single hormone molecule binding to a receptor can ultimately activate millions of proteins
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You are studying the effects of specific transcription factors on the activation of gene expression. You notice that one particular transcription factor binds far away from the promoter of its target gene. What can explain this?
A. The transcription factor transcribes small RNAs that then bind to the promoter and activate the gene's expression. B. The transcription factor tags the enhancer with ubiquitin to stimulate transcription. C. DNA looping brings the transcription factor closer to the promoter and initiates gene transcription. D. RNA looping brings the transcription factor closer to the promoter and initiates gene transcription. 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 transcriptional regulation? Consider Possibilities · Consider the different answer options. Which can you rule out? 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?
Fats are major constituents of
a. proteins. b. genes. c. photosynthesis. d. cell membranes. e. all of these.
The species concept defined as a group of organisms that are capable of interbreeding to produce fertile offspring is ________
A) the morphospecies concept B) the phylogenetic species concept C) the biological species concept D) the ecological species concept
If an organism is eukaryotic, then by definition it will:a
be assigned to the domain Bacteria. b. be assigned to the domain Archaea. c. be unicellular. d. possess gametangia. e. possess a nucleus