Flashcards
Chapter 2
Flashcards do conjunto (13)
- 1homologous chromosomescorresponding chromosomes usually alike in structure and size, and each carries genetic information for the same set of hereditary characteristics
- 2diploidcells that carry two sets of genetic information are (2n) ________
- 3haploidreproductive cells of eukaryotic organisms may contain a single set of chromosomes (n)
- 4centromerethe attachment point for spindle microtubules - the filaments responsible for moving chromosomes in cell division
- 5telomere________ protect and stabilize the chromosome ends
- 6sister chromatidsto prepare for cell division, each chromosome replicates. These two identical copies are called ________
- 73. What process leads to the production of sister chromatids, and when does it occur in the cell cycle?In preparation for cell division, each chromosome replicates creating an identical copy of itself. This occurs during the s phase (for DNA synthesis).
- 84. Assuming that DNA replication is perfect, why does mitosis guarantee that the daughter cells are genetically identical to the parent cell?The resulting daughter cells are genetically identical with one another and their parent cell because DNA synthesis in the s phase creates an exact copy of each DNA molecule, giving rise to two genetically identical sister chromatids. Mitosis then ensures that one of the two sister chromatids from each replicated chromosome passes into each new cell.
- 9synapsisa very close pairing association
- 10tetradeach homologous pair of synapsed chromosomes consists of four chromatids called a bivalent or ________
- 11crossing-overtakes place in prophase I, in which homologous chromosomes exchange genetic information. ________ generates genetic variation and is essential for the proper alignment and separation of chromosomes.
- 12recombinationcreating new combinations of alleles on a chromatid
- 138. How do the processes of meiosis and fertilization, when performed correctly, guarantee that all individuals of a species have the same number of chromosomes (at the same stage of the life cycle)?In meiosis, cohesin is protected at the centromeres during anaphase I, and so homologous chromosomes, but not sister chromatids, separate in meiosis I. The breakdown of centromeric cohesin allows sister chromatids to separate in anaphase II of meiosis.
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- FlashCards sobre Chapter 2, criado por Cora B. em 09-02-2018.
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- Cora B. · fev 2018
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- 9 fev 2018
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