click below
click below
Normal Size Small Size show me how
Advanced Higher
Unit 2 - Meiosis
Question | Answer |
---|---|
State the four features of homologous chromosomes | Same size, same gene loci, same banding pattern, same centromere location |
What is meiosis? | 2 cycles of nuclear division called meiosis I and meiosis II to produce haploid gametes that increase genetic variation during sexual reproduction. |
Where is meiosis located? = | Gamete mother cells and sex organs |
What is produced at the end of Meiosis I | 2 haploid cells that are genetically different |
What is produced at the end of Meiosis II | 4 haploid cells that are genetically different |
Explain the term random assortment. | Separation of parental chromosomes irrespective of their maternal or paternal origin |
Where does crossing over take place? | Chiasma(ta) |
Explain the term crossing over | Random crossing over at chiasmata resulting in exchange of DNA between homologous pairs and recombination of alleles of linked genes. |
In recombination, which genes will have a higher recombination frequency? | Genes that are further apart |
State the two ways organisms can use meiosis to produce gametes. | 1.gametes are formed directly from the cells produced by meiosis. 2. mitosis may occur after meiosis to form a haploid organism; gametes form later by differentiation |
Which stage of meiosis includes homologous chromsomes | Meiosis I |
Where does random assortment and crossing over occur? | When homologous chromosomes pair and line up along the metaphase plate |