How are plant and animal cells alike?

What is the name for a substance formed in a chemical reaction

Pls me i need this ! each cell has genes activated depending on it's job and what kind of cell it is. it is the presence of that causes the repressor protein to fall off and unblock the gene on the lac operon. if a gene is turned on then it is being an additional circular chromosome found in some bacteria that is used in genetic engineering.

When an object is moving away from you while still making a sound, the pitch of the sound is perceived to a. lower b. unchanged c. fluctuating d.higher