The trp repressor blocks transcription of the trp operon (B) when the repressor binds to tryptophan.
trp operon or the tryptophan operon codes enzymes for the amino acid tryptophan. The operon is on when the tryptophan is low in amount whereas the operon is off when the tryptophan is low in amount. The operon is an assimilation of five genes.
Repressor is a small protein that is supposed to prevent the synthesis of proteins. It does so binding to the operator gene. Therefore, presence or absence of repressor is a determining factor for an operon to be on or off.
To know more about trp operon, here
brainly.com/question/28239403
#SPJ4
Answer:
Using the number of amino acid differences, it would appear that the two birds are more closely related (had a common ancestor very recently), while the two fungi would have to trace their common ancestry much farther back in time (much more distantly related).
The answer to this question is evaporation
The level of productivity in oceans can be explained by the fact that the volume of the global ocean is enormous.
The oceans cover about 70% of the earth. This makes the ocean to occupy the largest volume on earth.
In spite of this large volume, the productivity of the ocean is just about 55 billion tons.
This low productivity of the ocean is tied to its large volume and small amount of primary productivity.
Learn more: brainly.com/question/22283115