Question

3
the process of mitosis are divided into four phases as shown in the diagram. match each description with the correct phase.
a. chromosomes line up in the middle of the cell on the spindle fibers
b. the dna coils up and becomes visible chromosomes as spindle fibers start to form.
c. two new nuclear membranes appear and chromosomes uncoil back into chromatin.
d. chromosomes split and are pulled to opposite ends of the cell
justify your thinking: i know that b describes ______ because...

Explanation:

To solve this, we recall the stages of mitosis:

• Prophase: Chromatin condenses into visible chromosomes, spindle fibers start to form, and the nuclear envelope breaks down. The description in part b ("The DNA coils up and becomes visible chromosomes as spindle fibers start to form") matches Prophase.
• Metaphase: Chromosomes line up at the cell's equator (middle) on spindle fibers (part a).
• Anaphase: Sister chromatids separate and are pulled to opposite poles (part d).
• Telophase: New nuclear membranes form, and chromosomes uncoil back to chromatin (part c).

For the justification of part B: Prophase is the stage where DNA (chromatin) condenses into visible chromosomes, and spindle fiber formation begins, which matches the description in B.

Answer:

I know that B describes Prophase because during Prophase, the DNA (in the form of chromatin) coils and condenses to become visible as chromosomes, and spindle fibers start to form, which matches the description "The DNA coils up and becomes visible chromosomes as spindle fibers start to form".