Section Handout - Week 2 - with answers

For example in interphase a cell is 2n 1c in prophase

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: own mutations in the gene that codes for hexosaminidase (Klug says 50, but the nature of any science text is that it is out of date as soon as the presses start to roll…) 3) Draw out a diagram of mitosis. Label the phases. Discuss the mnemonic PMAT. See Klug page 22. The key points are to know Interphase (before mitosis), then the mitotic stages of Prophase, Metaphase, Anaphase, Telophase. It’s good to know the chromosome number at each phase. For example, in Interphase a cell is 2N, 1C. In prophase a cell is 2N, 2C. At the end of Telophase, a cell becomes 2N, 1C again. Note the cell stays diploid all through mitosis. 4) Draw out a diagram of meiosis. Label Meiosis I & II, chiasmata, tetrad, dyad, and monad. Do this for an organism of n=2. Indicate where crossing over occurs. See Klug page 26. Once again, it’s good to know the chromosome number at each phase. At Prophase I, a cell is 2N,2C. Note that synapsis (crossing over) occurs in Prophase I. Note the tetrads in Metaphase I. By the end of Telophase I, the cell is 1N,2C. Meiosis I is the reductional division and Meiosis II is the equational division. For some reason, it helps me to chant “RE” to myself as away to remember reductional then equational. 5) Draw a chromosome as it might appear in a karyotype. Label major parts of the chromosome. How does it differ from a chromosome at a cell phase where a karyotype is not possible? The above chromosome is drawn in metaphase. This is the phase during which a karyotype is made. (...
View Full Document

Ask a homework question - tutors are online