If the experimental population of E. coli lacks an F factor or F plasmid, and if bacteriophage are excluded from the bacterial cultures, then which of these is a means by which beneficial mutations might be transmitted horizontally to other E. coli cells?

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#Question id: 2151

#SCPH28 | Zoology

Which of the following statement(s) is (are) true of transmembrane proteins?

a. All contain a hydrophobic α helix.

b. Some serve as membrane attachment sites for peripheral membrane proteins.

c. Some contain more than one membrane-spanning domain.

d. All are asymmetrically oriented in the lipid bilayer.

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#Question id: 5086

#SCPH01 Biochemistry

Cells move to new positions as an embryo establishes its three germ tissue layers during ________.

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#Question id: 15657

#SCPH01 Biochemistry

You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium.

You next construct a MelA– MelB– double mutant, which gives the following behavior:

 

Which of your two models is consistent with this new data?

a) the MelA- MelB- double mutant is identical to the MelB- mutant

b) MelA- is epistatic to MelB-

c) MelB- is epistatic to MelA-

d) the MelA- MelB- double mutant is identical to the MelA- mutant

Which of the following is the correct prediction about the double mutants?

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#Question id: 15711

#SCPH28 | Zoology

For the regeneration of a whole plant from a cell or callus tissue, there should be differentiation leading to shoot bud or embryo formation. This may occur through 

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#Question id: 14112

#I Life Science/ Life Sciences Group – I-V

Proteomics refers to the study of __________.