At about pH 7 in most cells, what happens to the amino R-group on an amino acid?
A) It acts as a base and gains a proton, giving it a positive charge.
B) It acts as an acid and loses a proton, giving it a negative charge.
C) It is reduced, and tends to act as an electron donor in redox reactions.
D) It remains neutral, like water, and does not have a charge.
Answer: A
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Clays often have positively-charged surfaces. How may this have been important in the formation of organic macromolecules?
A. They are a source of ATP to run chemical reactions. B. They form covalent bonds with organic building blocks. C. They can form templates by binding organic building blocks. D. They are a source of oxygen to break down organic building blocks. E. They are formed from meteorites that carried organic molecules to Earth.
All of the following are true about HIV EXCEPT
A. HIV contains an enzyme called reverse transcriptase. B. cDNA precedes double-stranded DNA. C. HIV carries RNA as its genetic material. D. HIV must reproduce immediately upon entering a host cell because it cannot survive a latent period.
Sugars can cyclize if they contain _______ or more carbons.
a. four b. five c. six d. eight
What is a thermocycler?
a. The process of cycling through the different temperatures of a PCR reaction 30 times b. The name for the DNA primers used in a PCR reaction c. The machine that controls the heat of the reaction, cycling between the different temperatures of the different steps during PCR d. The special DNA polymerase, used in a PCR reaction, that can tolerate the high temperatures