PRACTICAL 2 MITOSIS
PRACTICAL 2
Title: Modelling of mitosis
Objectives: To represent the pairs of homologous chromosomes by using pairs of model chromosomes.
Introduction:
Materials:
1. Noodles
2. Cutter
Method:
1. The pair of model chromosomes is used to demonstrate how the two chromosomes line up at the beginning of mitosis.
2. After that the way of the sister chromatids of each chromosome separate into two separate chromosomes is demonstrated.
3. The spindle fibers that pull the sister chromatids apart is represented by arms.
4. Next, the two different alleles for the gene that can result dwarship is obtained.
5. All four chromosomes are used to model the steps in mitosis.
6. The four chromosomes is demonstrated how the four chromosomes line up at the beginning of mitosis and how the sister chromatids of each chromosomes separate during mitosis.
7. The result is recorded.
Result:
AA or Aa or aa?
DD or Dd or dd?
Which alleles were present in the original cell (before DNA replication)
Aa
Dd
Which alleles are present in each daughter cell produced by mitosis?
AA
DD
Discussion: Questions:
1. Explain why sister chromatids could not have different alleles.
They cannot be different because when the DNA copies, it makes an exact copy of itself. Making it so that the alleles are the same. So it would be impossible for the alleles to be different.
2. Are the alleles in the daughter cells produced by mitosis the same as or different from the same alleles in the original cell?
Yes, the alleles in the daughter cells produced by mitosis are the same.
3. Explain how each daughter cell produced by mitosis receives exactly the same alleles as the original cell had.
Mitosis is the process, by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membranes into two cells containing roughly equal shares of these
Title: Modelling of mitosis
Objectives: To represent the pairs of homologous chromosomes by using pairs of model chromosomes.
Introduction:
Materials:
1. Noodles
2. Cutter
Method:
1. The pair of model chromosomes is used to demonstrate how the two chromosomes line up at the beginning of mitosis.
2. After that the way of the sister chromatids of each chromosome separate into two separate chromosomes is demonstrated.
3. The spindle fibers that pull the sister chromatids apart is represented by arms.
4. Next, the two different alleles for the gene that can result dwarship is obtained.
5. All four chromosomes are used to model the steps in mitosis.
6. The four chromosomes is demonstrated how the four chromosomes line up at the beginning of mitosis and how the sister chromatids of each chromosomes separate during mitosis.
7. The result is recorded.
Result:
AA or Aa or aa?
DD or Dd or dd?
Which alleles were present in the original cell (before DNA replication)
Aa
Dd
Which alleles are present in each daughter cell produced by mitosis?
AA
DD
Discussion: Questions:
1. Explain why sister chromatids could not have different alleles.
They cannot be different because when the DNA copies, it makes an exact copy of itself. Making it so that the alleles are the same. So it would be impossible for the alleles to be different.
2. Are the alleles in the daughter cells produced by mitosis the same as or different from the same alleles in the original cell?
Yes, the alleles in the daughter cells produced by mitosis are the same.
3. Explain how each daughter cell produced by mitosis receives exactly the same alleles as the original cell had.
Mitosis is the process, by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membranes into two cells containing roughly equal shares of these