Galactose imported into the yeast cell is converted to galactose 6-phosphate by a pathway involving six enzymes, whose genes are scattered over three chromosomes. Transcription of these genes is regulated by the combined actions of the proteins Gal4p, Gal80p, and Gal3p,

i. GAL3	a. Interaction with the Gal80p-Gal4p complex and activates Gal4p.
ii. GAL4	b. Recruits SAGA, Mediator, and TFIID to the galactose promoters, leading to DNA polymerase II recruitment and initiation of transcription
iii. GAL80	c. Transcriptional inhibitor
	d. Transcriptional activator

#Question id: 619

#Unit 1. Molecules and their Interaction Relevant to Biology

The benefit of measuring the initial rate of a reaction V0 is that at the beginning of a reaction:

#Question id: 620

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following statements about a plot of V0 vs. [S] for an enzyme that follows Michaelis-Menten kinetics is false?

#Question id: 621

#Unit 1. Molecules and their Interaction Relevant to Biology

Michaelis and Menten assumed that the overall reaction for an enzyme-catalyzed reaction could be written as Using this reaction, the rate of breakdown of the enzyme-substrate complex can be described by the expression:

#Question id: 622

#Unit 1. Molecules and their Interaction Relevant to Biology

An enzyme-catalyzed reaction was carried out with the substrate concentration initially a thousand times greater than the Km for that substrate.  After 9 minutes, 1% of the substrate had been converted to product, and the amount of product formed in the reaction mixture was 12 micromol.  If, in a separate experiment, one-third as much enzyme and twice as much substrate had been combined, how long would it take for the same amount (12 micromol) of product to be formed?

#Question id: 623

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of these statements about enzyme-catalyzed reactions is false?

#Question id: 624

#Unit 1. Molecules and their Interaction Relevant to Biology

The following data were obtained in a study of an enzyme known to follow Michaelis-Menten kinetics: The Km for this enzyme is approximately: