Meiosis and Sexual Life Cycles 10 Meiosis and Sexual Life Cycles Questions prepared by Brad Stith, University of Colorado Denver Louise Paquin, McDaniel College

Which of the following transmits genes from both parents to child, or from one generation of a family to another? DNA gametes somatic cells mitosis nucleotides Answer: B

Which of the following transmits genes from both parents to child, or from one generation of a family to another? DNA gametes somatic cells mitosis nucleotides 3

Fertilization is to zygote as meiosis is to which of the following? mitosis diploid chromosome replication gamete Answer: E Discuss why. 4

Fertilization is to zygote as meiosis is to which of the following? mitosis diploid chromosome replication gamete 5

Privet chromosomes undergo only mitosis. Privet shrubs and humans each have a diploid number of 46 chromosomes per cell. Why are the two species so dissimilar? Privet chromosomes undergo only mitosis. Privet chromosomes are shaped differently. Human chromosomes have genes grouped together differently. The two species have appreciably different genes. Privets do not have sex chromosomes. Answer: D 6

Privet chromosomes undergo only mitosis. Privet shrubs and humans each have a diploid number of 46 chromosomes per cell. Why are the two species so dissimilar? Privet chromosomes undergo only mitosis. Privet chromosomes are shaped differently. Human chromosomes have genes grouped together differently. The two species have appreciably different genes. Privets do not have sex chromosomes. 7

Why is it more practical to prepare karyotypes by viewing somatic diploid cells rather than haploid gametes? Answer: Cells can be made to divide and mitosis can be halted at metaphase; both sets of chromosomes need to be examined. 8

Diploid cells may undergo either mitosis or meiosis. Can haploid cells Diploid cells may undergo either mitosis or meiosis. Can haploid cells? Why or why not? Answer: Haploid cells cannot undergo meiosis because the chromosomes cannot pair. 9

How and at what stage do chromosomes undergo independent assortment? meiosis I pairing of homologs anaphase I separation of homologs meiosis II separation of homologs meiosis I metaphase alignment meiosis I telophase separation Answer: D 10

How and at what stage do chromosomes undergo independent assortment? meiosis I pairing of homologs anaphase I separation of homologs meiosis II separation of homologs meiosis I metaphase alignment meiosis I telophase separation 11

What allows sister chromatids to separate in which phase of meiosis? release of cohesin along sister chromatid arms in anaphase I crossing over of chromatids in prophase I release of cohesin at centromeres in anaphase I release of cohesin at centromeres in anaphase II crossing over of homologs in prophase I Answer: D 12

What allows sister chromatids to separate in which phase of meiosis? release of cohesin along sister chromatid arms in anaphase I crossing over of chromatids in prophase I release of cohesin at centromeres in anaphase I release of cohesin at centromeres in anaphase II crossing over of homologs in prophase I 13

What are three ways in which gametes from one individual diploid cell can be different from one another? Answer: mutation, crossing over, independent assortment 14

Prophase I of meiosis is generally the longest phase of meiosis Prophase I of meiosis is generally the longest phase of meiosis. Why might this be? Answer: Chromosomes must pair and cross over, besides the cell going through mitosis-like morphological changes such as spindle formation and chromosome condensation. 15

In this cell, what phase is represented? mitotic metaphase meiosis I anaphase meiosis I metaphase meiosis II anaphase meiosis II metaphase Answer: C (see Figure 10.8) 16

In this cell, what phase is represented? mitotic metaphase meiosis I anaphase meiosis I metaphase meiosis II anaphase meiosis II metaphase 17