While sampling marine plankton in a lab, a student encounters large numbers of fertilized eggs. The student rears some of the eggs in the laboratory for further study and finds that the blastopore becomes the mouth. The embryo develops into a trochophore larva and eventually has a true coelom. These eggs probably belonged to a(n)

#Question id: 558

#Unit 1. Molecules and their Interaction Relevant to Biology

In a plot of l/V against 1/[S] for an enzyme-catalyzed reaction, the presence of a competitive inhibitor will alter the:

#Question id: 559

#Unit 1. Molecules and their Interaction Relevant to Biology

In competitive inhibition, an inhibitor:

#Question id: 560

#Unit 1. Molecules and their Interaction Relevant to Biology

Vmax for an enzyme-catalyzed reaction:

#Question id: 561

#Unit 1. Molecules and their Interaction Relevant to Biology

Enzyme X exhibits maximum activity at pH = 6.9.  X shows a fairly sharp decrease in its activity when the pH goes much lower than 6.4.  One likely interpretation of this pH activity is that:

#Question id: 562

#Unit 1. Molecules and their Interaction Relevant to Biology

Phenyl-methane-sulfonyl-fluoride (PMSF) inactivates serine proteases by binding covalently to the catalytic serine residue at the active site; this enzyme-inhibitor bond is not cleaved by the enzyme.  This is an example of what kind of inhibition?

#Question id: 563

#Unit 1. Molecules and their Interaction Relevant to Biology

Both water and glucose share an —OH that can serve as a substrate for a reaction with the terminal phosphate of ATP catalyzed by hexokinase.  Glucose, however, is about a million times more reactive as a substrate than water.  The best explanation is that: