Question

how do chromosomes become visible under a light microscope as a cell prepares to divide?

chromosomes are created before cell division, and then broken down afterward.

chromosomes become more intensely colored before cell division.

the cell becomes flat and thin, and its internal structures become easier to see.

dna is thicker after it has replicated.

chromatin coils repeatedly until it appears as a short piece of strong rope.

Explanation:

• Option 1: Chromosomes are not "created" before division; they are condensed chromatin, so this is wrong.
• Option 2: Intense coloring isn't the reason; it's about condensation, so this is wrong.
• Option 3: Cell shape change isn't the key for chromosome visibility; it's about chromatin condensation, so this is wrong.
• Option 4: DNA replication makes it double - stranded, but the thickness from replication alone isn't the main reason for visibility. The key is chromatin condensation, so this is wrong.
• Option 5: During cell division preparation, chromatin (the uncondensed form of DNA) undergoes repeated coiling and condensation. This process makes it compact and visible under a light microscope, appearing like a short, thick structure (similar to a strong rope - like appearance).

Answer:

E. Chromatin coils repeatedly until it appears as a short piece of strong rope.