Answer:
An amino acid activates the repressor so that the repressor binds to the operator and prevents transcription.
Explanation:
In an operon, promoter is followed by operator which is finally followed by the structural genes to be transcribed. RNA Polymerase binds to the promoter and initiates transcription. A repressor can negatively control the transcription process by binding to the operator so that the RNA Polymerase is not able to move forward and transcription is halted.
For example: in trp operon, tryptophan amino acid binds to the repressor molecule which leads to change in repressor's shape. The repressor is now able to bind to the operator and prevent transcription.
For gradualism changes in species is slow an gradual, occurring in small period changes in the gene pool, whereas for punctuated equilibrium, evolution occurs in spurts of relatively rapid change with long periods of non- change.
The parasite can live<span> in the environment for many months and contaminate soil, water, fruits and vegetables, sandboxes, grass where animals graze for food, litter boxes, or any place where an infected cat may have defecated. </span>Toxoplasmosis<span> is an infection caused by a microscopic parasite called </span>Toxoplasma<span> gondii.</span>
<span>A population's growth is strongly influenced by the proportions of individuals in different age brackets, which in turn is influenced by economic development.</span>
Conduction convection radiation
