Mitosis EXAM PREP WITH COMPLETE
SOLUTION
The events that take place during interphase in mitosis leads to the production of two
genetically identical cells. EXPLAIN how. - =DNA replication takes place during interphase which
involves specific complementary base pairing taking place. Sister chromatids move to opposite
poles.
Mikanolide is a drug that inhibits the enzyme DNA polymerase. Explain why this drug may be
effective against some types of cancer. - =Prevents DNA replication. Prevents mitosis.
Nucleotides of new strand not joined together.
IPMAT - =Interphase, prophase, metaphase, anaphase, telophase.
Describe the role of the centromere in mitosis. - =Holds chromatids together.
Attaches chromatids to spindle.
Allows chromatids to move to opposite poles.
Cells lining the human intestine complete the cell cycle in a short time. Explain the advantage of
these cells completing the cell cycle in a short time. - =Replace cells rapidly.
Homologous chromosomes carry the same genes but they are not genetically identical. Explain
why. - =Homologous chromosomes carry different alleles
Other than independent segregation, give 2 ways in which meiosis allows the
production of genetically different cells. - =Crossing over where alleles are exchanged between
chromosomes.
Genetic recombination
, A doctor investigated the number of cells in different stages of the cell cycle in two tissue
samples, C and D. One tissue sample was taken from a cancerous tumour. The other was taken
from a non cancerous tissue. Explain how the doctor could have recognised which cells were in
interphase when looking at the tissue samples. - =No visible chromosomes but the nucleus
would be visible.
A doctor investigated the number of cells in different stages of the cell cycle in two tissue
samples, C and D. One tissue sample was taken from a cancerous tumour. The
other was taken from non-cancerous tissue. Which tissue sample, C or D, was taken from a
cancerous tumour?
Use information in the table to explain your answer. - =D because there are a lower percentage
of cells in interphase and a higher percentage of cells in mitosis. This means more cells are
dividing.
Describe the APPEARANCE and BEHAVIOUR of chromosomes during mitosis. - =During prophase
chromosomes, condense, thicken, shorten and become more visible. Chromosomes appear as
two sister chromatids joined at the centromere.
During metaphase chromosomes line up on the equator. Chromosomes are attached to spindle
fibres by the centromere. During anaphase the centromere splits and the sister chromatids are
pulled to opposite poles of the cell.
During telophase chromatids chromosomes recoil and become longer and thinner.
The student concluded that the cell in Figure 1 was in the anaphase stage of mitosis. Was she
correct? Give two reasons for your answer. - =Yes because chromatids are in two groups at
poles of spindles.V shape shows that sister chromatids have been pulled apart at their
centromeres.
Describe what happens after telophase to complete the process of cell division. - =Uncoiling
and elongation of chromosomes. Formation of nuclear membranes. Loss of spindle fibres. Two
genetically identical daughter cells formed.
Give one piece of evidence from the bar chart which indicates that these cells are dividing
rapidly. - =short duration of interphase;
SOLUTION
The events that take place during interphase in mitosis leads to the production of two
genetically identical cells. EXPLAIN how. - =DNA replication takes place during interphase which
involves specific complementary base pairing taking place. Sister chromatids move to opposite
poles.
Mikanolide is a drug that inhibits the enzyme DNA polymerase. Explain why this drug may be
effective against some types of cancer. - =Prevents DNA replication. Prevents mitosis.
Nucleotides of new strand not joined together.
IPMAT - =Interphase, prophase, metaphase, anaphase, telophase.
Describe the role of the centromere in mitosis. - =Holds chromatids together.
Attaches chromatids to spindle.
Allows chromatids to move to opposite poles.
Cells lining the human intestine complete the cell cycle in a short time. Explain the advantage of
these cells completing the cell cycle in a short time. - =Replace cells rapidly.
Homologous chromosomes carry the same genes but they are not genetically identical. Explain
why. - =Homologous chromosomes carry different alleles
Other than independent segregation, give 2 ways in which meiosis allows the
production of genetically different cells. - =Crossing over where alleles are exchanged between
chromosomes.
Genetic recombination
, A doctor investigated the number of cells in different stages of the cell cycle in two tissue
samples, C and D. One tissue sample was taken from a cancerous tumour. The other was taken
from a non cancerous tissue. Explain how the doctor could have recognised which cells were in
interphase when looking at the tissue samples. - =No visible chromosomes but the nucleus
would be visible.
A doctor investigated the number of cells in different stages of the cell cycle in two tissue
samples, C and D. One tissue sample was taken from a cancerous tumour. The
other was taken from non-cancerous tissue. Which tissue sample, C or D, was taken from a
cancerous tumour?
Use information in the table to explain your answer. - =D because there are a lower percentage
of cells in interphase and a higher percentage of cells in mitosis. This means more cells are
dividing.
Describe the APPEARANCE and BEHAVIOUR of chromosomes during mitosis. - =During prophase
chromosomes, condense, thicken, shorten and become more visible. Chromosomes appear as
two sister chromatids joined at the centromere.
During metaphase chromosomes line up on the equator. Chromosomes are attached to spindle
fibres by the centromere. During anaphase the centromere splits and the sister chromatids are
pulled to opposite poles of the cell.
During telophase chromatids chromosomes recoil and become longer and thinner.
The student concluded that the cell in Figure 1 was in the anaphase stage of mitosis. Was she
correct? Give two reasons for your answer. - =Yes because chromatids are in two groups at
poles of spindles.V shape shows that sister chromatids have been pulled apart at their
centromeres.
Describe what happens after telophase to complete the process of cell division. - =Uncoiling
and elongation of chromosomes. Formation of nuclear membranes. Loss of spindle fibres. Two
genetically identical daughter cells formed.
Give one piece of evidence from the bar chart which indicates that these cells are dividing
rapidly. - =short duration of interphase;
