Posted: February 5th, 2019

BIO/350 Week 6 Mitosis and Meiosis Lab Assignment

LAB REPORT ASSISTANTThis document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor.OBSERVATIONSExercise 1: Mitosis in Animal and Plant CellsPROCEDURE1. Observe the prepared slide of the whitefish blastula under the microscope.2. Draw cells that represent the various stages of mitosis: Interphase, Prophase, Metaphase, Anaphase, and Telophase. Place your drawings here:3. For each drawing, label the parts of the cells that you can identify such as the nuclear membrane, chromosomes, cellular membrane, cytoplasm, spindle fibers, chromatids, cleavage furrow formation during Cytokinesis, and centrioles. It is unlikely that you will find all of these structures. Why?4. Observe the slide of the onion root tip under the microscope.5. Draw cells that represent the various stages of mitosis: Interphase, Prophase, Metaphase, Anaphase and Telophase. Place your drawings here:6. Label the parts of the cells that you can identify such as the nuclear membrane, chromosomes, cellular membrane, cytoplasm, spindle fibers, chromatids, cell wall formation region, and centrioles. It it is unlikely that you will find all of these structures. Why?RESULTSFor both the whitefish and the onion, what is the 2n number of chromosomes that were observed?Hint: separate chromosomes are easiest to view and count during Prometaphase.QUESTIONSA. What is the purpose of mitosis?B. What other term is commonly used in place of “mitosis”?C. What is a blastula?D. What are the differences in the mitotic processes between animal and plant cells?E. Why might there be more mitotic division in an onion root tip than in other areas of the plantF. A summary of mitosis – fill in the correct answer. The nucleus in the undivided cell has the diploid (2n) number of chromosomes, and the nuclei in the two split cells also have number of chromosomes. In mitosis, the chromosome number (check the correct choice) stays the same or halves.Exercise 2: Meiosis in AnimalsQUESTIONSA. Which organ, the ovary or the testes, contained the greater number of gametes? B. What may be a reason for this?Exercise 3: Simulating MeiosisQUESTIONSA. What does mitosis accomplish?B. When and where does mitosis occur?C. What does meiosis accomplish?D. When and where does meiosis occur?E. How do these two processes differ?F. How do Prophase in Mitosis and Prophase I in Meiosis differ?G. Does Meiosis occur anywhere else in the body beside within the gonads?. How does meiosis confer advantages to an organism when compared to asexual reproduction such as budding?. How might crossing-over be a benefit to an organism?How might crossing-over be detrimental to an organism?. Crossing over can also occur during mitosis where chromosomes exchange segments. Is crossing over more advantageous to organism survival if it occurs during mitosis or meiosis? Explain.LABORATORY SUMMARYWhat haveyou learned from doing this laboratory?