Which of the following is a purine?
A) guanine
B) cytosine
C) thymine
D) uracil
E) cysteine
A) guanine
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Mycorrhizae are the mutualistic relationship between fungi and the roots of certain plants.
Answer the following statement true (T) or false (F)
What basal transcription factor is most often affected by regulatory transcription factors?
A. TFIIB B. TFIID C. TFIIE D. TFIIF
What would happen to a plant that is treated with a chemical that prevents electrons from moving through the electron transport chain?
A. It could no longer produce CO2. B. Water would be broken down to form oxygen at a higher rate to compensate. C. It could not generate an electrochemical H+ gradient across a membrane. D. It could not produce NADP+. E. More electrons would be available for the light harvesting array.
The relatively simple excretory system used by flatworms consists of tubules called
a. nephrons. b. hepatic tubules. c. metanephridia. d. Malpighian tubules. e. protonephridia.