THE CELL
CELL COMMUNICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It divides the cell in half.
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It duplicates the DNA.
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It breaks down the nuclear membrane.
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It helps separate the chromosomes.
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Detailed explanation-1: -Mitotic spindle, present at the poles of the cells, is a structure made of microtubules (spindle fibres). Its role is to separate the chromosomes. The spindle fibres attach to chromosomes during metaphase and pull the chromatids towards opposite poles during anaphase.
Detailed explanation-2: -The spindle is necessary to equally divide the chromosomes in a parental cell into two daughter cells during both types of nuclear division: mitosis and meiosis. During mitosis, the spindle fibers are called the mitotic spindle.
Detailed explanation-3: -Spindle fibers from one side of the cell attach to one of the sister chromatids. The spindle fibers from the other side of the cell attach to the other sister chromatids of the chromosome. They attach at a point called the kinetochore, which is a disk or protein that is on each side of the centromere.
Detailed explanation-4: -As mitosis progresses, the microtubules attach to the chromosomes, which have already duplicated their DNA and aligned across the center of the cell. The spindle tubules then shorten and move toward the poles of the cell. As they move, they pull the one copy of each chromosome with them to opposite poles of the cell.