Test On Nucleic Acids Enzymes 80÷100 Flashcards
Competitive inhibition
Line drawn with competitive inhibitor inhibits enzyme that turns starch into maltose. B
Line drawn without inhibitor. A
How could you tell that the line B was competitive inhibition.
At high substrate concentration rate approaches rate in absence of inhibitor.
When calculating rate
Make sure to use exactly the same units as the axis.
Explain how pairing of nitrogenous bases allows identical copies of DNA to be made.
Purines always pair with pyrimidines because they are different sizes. Adenine pairs with thymine, cytosine pairs with guanine because they are complementary based. They form hydrogen bonds 2 between AT and 3 between CG. Therefore if one base is known it can pair with only one other base.
A DNA molecule contains two poly nucleotide chains. Describe how these two chained are held together.
They are held together by hydrogen bonds between nitrogenous bases. Adenine and thymine are complementary to each other and form two hydrogen bonds. And three hydrogen bonds from between cytosine and guanine. Also purines bond to pyrimidines.
Phosphodiester bonds between nucleotides form the backbone.
Which if the following does not affect shape of active site.
Drop in temp
Non comp inhibitor
Change in pH
Binding of substrate
Its first one.
Enzymes digest insects that fall into heliamphora traps.
Is mode of action of these enzymes extracellular or intracellular? Explain your answer.
Extracellular. Digestion is occurring in leaf. Not inside cells. Enzymes are released by plant cells, into traps.
Explain competitive inhibtion
Inhibitor is similar shape to the substrate and therefore prevents the substrate from entering active site. And usually the inhibitor binds to the active site temporarily.
