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.
What happens to chromosomes during mitosis a level?
In the first stage of mitosis, prophase, the chromosomes become visible due to shortening and condensing, each chromosome is made up of two sister chromatids joined at the centromere that may not be visible until late prophase. During metaphase, the chromosomes line up on the equator of the spindle.
What happens to the structure of the chromosomes after mitosis?
Mitosis ends with telophase, or the stage at which the chromosomes reach the poles. The nuclear membrane then reforms, and the chromosomes begin to decondense into their interphase conformations. Telophase is followed by cytokinesis, or the division of the cytoplasm into two daughter cells.
What is special about the two cells produced in mitosis?
In mitosis, two cells called daughter cells are produced. It is essential that any new daughter cells produced contain genetic information that is identical to the mother cell, and that the number of chromosomes remains constant.
How many chromosomes are in each daughter cell at the end of mitosis?
At the end of mitosis, the two daughter cells will be exact copies of the original cell. Each daughter cell will have 30 chromosomes. At the end of meiosis II, each cell (i.e., gamete) would have half the original number of chromosomes, that is, 15 chromosomes. 2.
Why do chromosomes double during mitosis?
The unzipped DNA half strand is then matched up with a newly formed half strand. Because both halves receive a new half strand, the cell ends up with a double set of chromosomes.
Why are chromosomes duplicated before mitosis?
Then, at a critical point during interphase (called the S phase), the cell duplicates its chromosomes and ensures its systems are ready for cell division. If all conditions are ideal, the cell is now ready to move into the first phase of mitosis.
What does N mean in mitosis?
If a haploid cell has n chromosomes, a diploid cell has 2n (n represents a number, which is different for every species – in humans, for example, n = 23 and 2n = 46). … Therefore, if a diploid cell undergoes mitosis, the result is two identical diploid cells (2n →2n).