CELL STRUCTURES AND FUNCTION
CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The chromosomes become visible; nucleus disappear; spindles form
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The chromosomes align in the middle of the cell
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The sister chromatids separate
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The chromosomes uncoil into chromatin; nucleus reappears; spindles disappear
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Detailed explanation-1: -During prophase, the nucleus disappears, spindle fibers form, and DNA condenses into chromosomes (sister chromatids). During metaphase, the sister chromatids align along the equator of the cell by attaching their centromeres to the spindle fibers.
Detailed explanation-2: -Prophase is the first phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells. During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses.
Detailed explanation-3: -During prophase, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down.
Detailed explanation-4: -During the prophase stage, the chromosomes condense into an X-shaped structure. Each chromosome is composed of two sister chromatids with the same information. Chromosomes are paired, both copies of chromosome 1 are combined, and both copies of chromosome 2 are grouped together.
Detailed explanation-5: -When prophase is complete, the cell enters prometaphase-the second stage of mitosis. During prometaphase, phosphorylation of nuclear lamins by M-CDK causes the nuclear membrane to break down into numerous small vesicles. As a result, the spindle microtubules now have direct access to the genetic material of the cell.