Download Mitosis/Meiosis Modeling Lab Analysis Questions – Answer Key

Mitosis/Meiosis Modeling Lab Analysis Questions – Answer Key
Mitosis Modeling
If a cell contains a set of duplicated chromosomes, does it contain any more genetic
information than the cell before the chromosomes were duplicated?
No. There is twice the amount of genetic material but no additional different genetic
information.
What is the significance of the fact that the chromosomes condense before they are moved?
It allows the condensed, distinct chromosomes to be moved, aligned on the metaphase
plate, and divided properly into 2 daughter cells.
How are the chromosome copies, called sister chromatids, separated from each other?
Cohesion proteins in the centromere are broken down and then the mitotic spindle fibers
pull the two sister chromatids (now individual chromosomes) to the two separate poles.
Meiosis Modeling
How does the process increase genetic diversity?
 Crossing over generates recombinant chromosomes with new gene allele
combinations
 Independent assortment creates essentially unique gametes
How does the distance between two genes or a gene and a centromere affect crossover
frequencies?
The further genes are apart from each other, the more likely that a crossing over event will
occur between them.
When is the DNA replicated during meiosis?
During S phase of Interphase – prior to Meiosis I
How does Independent Assortment relate to meiosis?
When the homologous pairs of chromosomes line up on the metaphase plate during
Meiosis I, they do so independently of other pairs.
How can you calculate the possible number of different kinds of gametes?
Because of independent assortment, the number of different gametes possible is 2n, where
n=the number of homologous pairs. In humans it is 223 possible combinations.
How are mitosis & meiosis fundamentally different?
Mitosis = one cell division cycle which produces two genetically identical diploid (2N)
daughter cells
Meiosis = two rounds of cell division which produces four genetically unique haploid (N)
daughter cells called gametes