Question

a chemical from outside a cell that promotes cell division is called a
○ growth factor.
○ nutrient.
○ telomere.
○ mutagen.
○ promoter.

Explanation:

• A growth factor is a chemical (usually a protein or peptide) that acts from outside a cell to stimulate cell division and growth.
• A nutrient is a substance used for energy, building materials, etc., not specifically for promoting cell division.
• A telomere is a region at the end of a chromosome, not a chemical promoting cell division.
• A mutagen is an agent that causes mutations, not related to promoting cell division.
• A promoter is a DNA sequence (not a chemical from outside the cell) that initiates transcription.

Answer:

A. growth factor