Biology lab work 5 assistance
INSTRUCTIONS:
· On your own and without assistance, complete this Lab 5Answer Sheet electronically and submit it via the Assignments Folder by the date listed intheCourse Schedule (under Syllabus).
· To conduct your laboratory exercises, use the Laboratory Manual located under Course Content. Read the introduction and the directions for each exercise/experiment carefully before completing the exercises/experiments and answering the questions.
· Save your Lab 5Answer Sheet in the following format: LastName_Lab5 (e.g., Smith_Lab5).
· You should submit your document as a Word (.doc or .docx) or Rich Text Format (.rtf) file for best compatibility.
Pre-Lab Questions
- What major event occurs during interphase?
- A person, residing in a location where they are exposed to the sun often, develops a mutation in some of their skin cells resulting in cancer. Consider whether their offspring will be born with the same mutation. Use scientific evidence to support your answer.
Experiment 1: Following Chromosomal DNA Movement through Meiosis
Data Tables and Post-Lab Assessment
Part 1 – Meiotic Division Beads Diagram without Crossing Over
Prophase I
Metaphase I
Anaphase I
Telophase I
Prophase II
Metaphase II
Anaphase II
Telophase II
Cytokinesis
Part 2: Meiotic Division Beads Diagram with Crossing Over
Prophase I
Metaphase I
Anaphase I
Telophase I
Prophase II
Metaphase II
Anaphase II
Telophase II
Cytokinesis
Post-Lab Questions
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What is the ploidy of the DNA at the end of meiosis I? What about at the end of meiosis II?
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How are meiosis I and meiosis II different?
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Why do you use non-sister chromatids to demonstrate crossing over?
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What combinations of alleles could result from a crossover between BD and bd chromosomes?
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How many chromosomes were present when meiosis I started?
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How many nuclei are present at the end of meiosis II? How many chromosomes are in each?
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Identify two ways that meiosis contributes to genetic recombination.
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Why is it necessary to reduce the number of chromosomes in gametes, but not in other cells?
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Blue whales have 44 chromosomes in every cell. Determine how many chromosomes you would expect to find in the following:
Sperm Cell:
Egg Cell:
Daughter Cell from Meiosis I:
Daughter Cell from Meiosis II:
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Research and find a disease that is caused by chromosomal mutations. When does the mutation occur? What chromosomes are affected? What are the consequences?
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Diagram what would happen if sexual reproduction took place for four generations using diploid (2n) cells.
Experiment 2: The Importance of Cell Cycle Control
Data
Post-Lab Questions
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Record your hypothesis from Step 1 in the Procedure section here.
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What do your results indicate about cell cycle control?
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Suppose a person developed a mutation in a somatic cell which diminishes the performance of the body’s natural cell cycle control proteins. This mutation resulted in cancer, but was effectively treated with a cocktail of cancer-fighting techniques. Is it possible for this person’s future children to inherit this cancer-causing mutation? Be specific when you explain why or why not.
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Why do cells which lack cell cycle control exhibit karyotypes which look physically different than cells with normal cell cycle.
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What are HeLa cells? Why are HeLa cells appropriate for this experiment?