9. Mitosis and Meiosis

Which checkpoint is responsible for ensuring the DNA was replicated properly?

How do we know that mitotic chromosomes are derived from chromatin?

How do we know that DNA replication occurs during interphase, not early in mitosis?

How do we know that chromosomes exist in homologous pairs?

Examine the following diagrams of cells from an organism with diploid number 2n=6, and identify what stage of M phase is represented.

Our closest primate relative, the chimpanzee, has a diploid number of 2n = 48. For each of the following stages of M phase, identify the number of chromosomes present in each cell.

Mitotic metaphase

Our closest primate relative, the chimpanzee, has a diploid number of 2n = 48. For each of the following stages of M phase, identify the number of chromosomes present in each cell.

Early mitotic prophase

Our closest primate relative, the chimpanzee, has a diploid number of 2n = 48. For each of the following stages of M phase, identify the number of chromosomes present in each cell.

End of mitotic telophase

What role do the following cellular components play in the storage, expression, or transmission of genetic information?

(a) Chromatin

(b) Nucleolus

(c) Ribosome

(d) Mitochondrion

(e) Centriole

(f) Centromere

Discuss the concepts of homologous chromosomes, diploidy, and haploidy. What characteristics do two homologous chromosomes share?

Describe the organization of the interphase nucleus. Include in your presentation a description of chromosome territories, interchromatin compartments, and transcription factories.

If two chromosomes of a species are the same length and have similar centromere placements and yet are not homologous, what is different about them?

Describe the events that characterize each stage of mitosis.

How are chromosomes named on the basis of their centromere placement?

Contrast telophase in plant and animal mitosis.