10.1 Meiosis Flashcards
1
Q
Define interkinesis
A
An optional rest period between meiosis I and meiosis II, no DNA replication occurs in this stage
2
Q
Outline the formation of chiasma
A
- During synapsis in Prophase I, homologous chromosomes form tetrads
- Portions of non-sister chromatids overlap, break at chiasmata, reattach to new non-sister chromatid in a system of reciprocal exchange
- New combinations known as recombinants
- Portions of non-sister chromatids overlap, break at chiasmata, reattach to new non-sister chromatid in a system of reciprocal exchange
3
Q
Explain how genetic variety is produced through independent assortment
A
- Variety produced by recombination of maternal and paternal chromosomes
- For each pair of homologous chromosomes, maternal and paternal chromosomes assort to daughter cells randomly
4
Q
Explain how genetic variety is produced through crossing over
A
- Variety produced by recombination within individual chromosomes
- During synapsis in Prophase I, homologous chromosomes form tetrads
- Portions of non-sister chromatids overlap, break at chiasmata, reattach to new chromatid in a system of reciprocal exchange
- New combinations known as recombinants
5
Q
State Mendel’s law of independent assortment
A
“Two or more pairs of alleles assort independently of one another during gamete formation”
• This law states that allele pairs separate independently during the formation of gametes
• Therefore, traits are transmitted to offspring independently of one another
6
Q
Explain the relationship between Mendel’s law of independent assortment and meiosis
A
- Mendel’s law of independent assortment applies only to traits carried on different chromosomes (unlinked genes)
- Independent assortment occurs as a result of the alignment of homologs during Metaphase I, determining which maternal and paternal chromosomes assort to each daughter cell
- Each pair of alleles separates independently of every other pair of unlinked alleles
- Independent assortment occurs as a result of the alignment of homologs during Metaphase I, determining which maternal and paternal chromosomes assort to each daughter cell