Melaku Michael Online Onion Root Tips Lab Determining time spent in different phases of the cell cycle The assignment: In this activity, you will be presented with cells from the tip of an onion root. You will classify each cell based on what phase it is in. At the end you will count up the cells found in each phase and use those numbers to predict how much time a dividing cell spends in each phase. Copy this table into a word processing document. You can enter data in this table as you go along, or at the end of the activity. Submit your work to the Onion Root Tip Lab dropbox. T o t a l 3 6 1 0 0 % Interphase number of cells Prophase Metaphase Anaphase Telophas e 20 10 3 2 1 percent of cells 54% 27% 8.1% 5.4% 2.7% Go to the following website. To begin, click next at the bottom of the screen. It will take you through a series of cells going through Mitosis. You will fill in the chart at the end of the activity. You will classify 36 different cells. http://www.biology.arizona.edu/cell_bio/activities/cell_cycle/assignment.html Once you have filled in the chart answer the following conclusion questions. Copy and paste them into the same MS Word document. 1. What phase are most cells found in? Interphase 2. What type of cells undergo mitosis? Somatic cells 3. What happens during metaphase? The chromosomes, now at their most highly coiled and condensed, become arranged on a plane equidistant from the two poles called the metaphase plate 4. What is the purpose of the spindle fibers? To pull the chromosome sister pairs apart. 5. What is happening during Interphase? During Interphase the cellular count of the cells doubles and the copy is finished. 6. Explain how the process of mitosis helps an organism to grow in size. Mitosis helps an organism grow in size because the process of mitosis is multiplying the daughter cells by two thus increasing the count of similar somatic cells thus increasing the organisms size.