The average daily temperature change on an exposed south-facing slope and a north-facing slope for a late summer day in the Northern Hemisphere are shown below.

Compared with a south-facing slope, the climatic conditions on a north-facing slope favour the formation of a vegetation community best adapted to

#Question id: 3980

#Unit 3. Fundamental Processes

Which of the following statements correctly describes promoters in E. coli?

#Question id: 3981

#Unit 3. Fundamental Processes

The diagram below represents a hypothetical operon in the bacterium E. coli.  The operon consists of two structural genes (A and B), which code for the enzymes A-ase and B-ase, respectively, and also includes P (promoter) and O (operator) regions as shown.

 When a certain compound (X) is added to the growth medium of E. coli, the separate enzymes A-ase and B-ase are both synthesized at a 50-fold higher rate than in the absence of X.  (X has a molecular weight of about 200.)  Which of the following statements is true of the operon decribed above?

#Question id: 3982

#Unit 3. Fundamental Processes

The diagram below represents a hypothetical operon in the bacterium E. coli.  The operon consists of two structural genes (A and B) that code for the enzymes A-ase and B-ase, respectively, and also includes P (promoter) and O (operator) regions as shown.

 When a certain compound (X) is added to the growth medium of E. coli, the separate enzymes A-ase and B-ase are both synthesized at a 50-fold higher rate than in the absence of X (which has a molecular weight of about 200).  Which one of the following statements is true of such an operon?

#Question id: 3983

#Unit 3. Fundamental Processes

Transcription of the lactose operon in E. coli is stimulated by:

#Question id: 3984

#Unit 3. Fundamental Processes

Which of the following statements about regulation of the lac operon is true?

#Question id: 3985

#Unit 3. Fundamental Processes

The binding of CRP (cAMP receptor protein of E. coli) to DNA in the lac operon: