The lactose operon is under both positive and negative regulation. A bacterial cell does not want to waste the energy to synthesize enzymes to degrade an energy source if that energy source is not present therefore, the lactose operon is regulated to produce enzymes to break down lactose only if lactose is present. When lactose is absent we would expect ALL BUT ONE of these steps to occur.
A) The lac repressor is deactivated.
B) The repressor binds the operator.
C) The lac repressor protein is synthesized in its active form.
D) RNA polymerase is blocked from binding to the promoter sequence.

a

explanation:

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it

acceleration = 18/3 = 6 m/s per second.

hope i

-lavira: )

the nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and dna, the building blocks of all life. plants absorb nitrogen in the form of ammonium, nitrate ion and, on rare occasions, as amino acids. animals receive nitrogen necessary for biological processes from feeding on living or dead organic matter.