Question
Which curve shows the concentration of product during the course of an enzyme-catalysed
reaction?
Answer/Explanation
Question
What is a function of the enzyme helicase?
A. It coils DNA up into a double helical shape.
B. It links DNA nucleotides in a new DNA strand.
C. It breaks hydrogen bonds between the DNA strands.
D. It forms temporary hydrogen bonds to produce messenger RNA.
Answer/Explanation
Question
The apparatus shown was used to investigate the effect of varying carbon dioxide concentration on
the rate of photosynthesis. Carbon dioxide concentrations were varied by adding different amounts
of sodium hydrogen carbonate \((NaHCO_3)\) to water.
What is the dependent variable in this investigation?
A. Temperature
B. Light intensity
C. Amount of NaHCO3 added
D. Volume of oxygen produced
Answer/Explanation
Question
What is the minimum number of nucleotides needed to code for a polypeptide composed of 210 amino acids?
A. 70
B. 210
C. 420
D. 630
Answer/Explanation
Question
The graph shows the changes in lactate measured in an athlete’s blood during exercise.
Which hypothesis provides the most likely explanation for the curve?
A. As exercise intensity increases, lactate is converted back to glucose.
B. Anaerobic exercise results in high levels of lactate.
C. Lactate provides energy for intense exercise.
D. Under anaerobic conditions the body produces less lactate.