2025 BIO 201L COMPLETE Lab 3 Mitosis and Meiosis
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Student Name:
Access Code:
Lab Report Format Expectations
Utilize college level grammar and professional formatting when completing this
worksheet. Submissions without proper formatting, all required photos or
sufficient responses will be rejected. Pre-lab Questions
1. What are chromosomes made of?
Chromosomes are composed of a single, tightly coiled strand of DNA
wrapped around proteins called histones.
2. Compare and contrast mitosis and meiosis, ensuring to detail the
differences in both function and in process. (Hint: Your response
should be 4-5 sentences long.)
Mitosis and meiosis are both forms of cell division, but they serve different
purposes. Mitosis creates two identical daughter cells used for growth and
repair, while meiosis generates four non-identical gametes for
reproduction. Mitosis has one round of division, whereas meiosis has two
rounds. Additionally, meiosis includes crossing over, which introduces
genetic variation.
3. Cancer is a disease related to uncontrolled cell division. Investigate two
known causes for these rapidly dividing cells and use this knowledge to
invent a drug that would inhibit the growth of cancer cells. (Hint: Your
response should be 4-5 sentences long.)
Uncontrolled cell division in cancer can result from mutations in tumor
suppressor genes or overstimulation of growth signals. A potential drug
,could target specific cancer receptors using antibody-drug conjugates to
block the signals or trigger cell death in mutated cells.
, EXPERIMENT 1: OBSERVATION OF MITOSIS IN A PLANT CELL
Introduction Questions
1. State how you will calculate the number of hours each stage of mitosis takes
To calculate the hours for each stage: (Number of cells in stage ÷ Total
number of cells counted) × 24 = Hours in that stage.
2. In Table 1, below, predict how many hours of the 24-hour cell cycle you
think each step takes. Ensure you provide robust supporting evidence to
back your prediction.
Table 1: Mitosis Predictions
Since mitosis consists of 4 stages (prophase,
Predictions metaphase, anaphase, and telophase), I estimate that
it will take 3 - 4 hours for these stages
Interphase usually last up to 20 - 21 hours. Therefore
Supporting Evidence taking the maxiumum, 24 - 4 = 20 hours
Data and Observations
Record your observations in the table below. Based on those observations,
calculate the percentage of time spent in each phase of mitosis.
Table 2: Mitosis Data
Chosen Image Onion Root Tip 100x image number 4
Stage Number of Cells in Total Number Calculated % of
Stage of Cells Time Spent in
Stage
Interphase 20 25 40%
Prophase 2 25 8%
Straighterline
Student Name:
Access Code:
Lab Report Format Expectations
Utilize college level grammar and professional formatting when completing this
worksheet. Submissions without proper formatting, all required photos or
sufficient responses will be rejected. Pre-lab Questions
1. What are chromosomes made of?
Chromosomes are composed of a single, tightly coiled strand of DNA
wrapped around proteins called histones.
2. Compare and contrast mitosis and meiosis, ensuring to detail the
differences in both function and in process. (Hint: Your response
should be 4-5 sentences long.)
Mitosis and meiosis are both forms of cell division, but they serve different
purposes. Mitosis creates two identical daughter cells used for growth and
repair, while meiosis generates four non-identical gametes for
reproduction. Mitosis has one round of division, whereas meiosis has two
rounds. Additionally, meiosis includes crossing over, which introduces
genetic variation.
3. Cancer is a disease related to uncontrolled cell division. Investigate two
known causes for these rapidly dividing cells and use this knowledge to
invent a drug that would inhibit the growth of cancer cells. (Hint: Your
response should be 4-5 sentences long.)
Uncontrolled cell division in cancer can result from mutations in tumor
suppressor genes or overstimulation of growth signals. A potential drug
,could target specific cancer receptors using antibody-drug conjugates to
block the signals or trigger cell death in mutated cells.
, EXPERIMENT 1: OBSERVATION OF MITOSIS IN A PLANT CELL
Introduction Questions
1. State how you will calculate the number of hours each stage of mitosis takes
To calculate the hours for each stage: (Number of cells in stage ÷ Total
number of cells counted) × 24 = Hours in that stage.
2. In Table 1, below, predict how many hours of the 24-hour cell cycle you
think each step takes. Ensure you provide robust supporting evidence to
back your prediction.
Table 1: Mitosis Predictions
Since mitosis consists of 4 stages (prophase,
Predictions metaphase, anaphase, and telophase), I estimate that
it will take 3 - 4 hours for these stages
Interphase usually last up to 20 - 21 hours. Therefore
Supporting Evidence taking the maxiumum, 24 - 4 = 20 hours
Data and Observations
Record your observations in the table below. Based on those observations,
calculate the percentage of time spent in each phase of mitosis.
Table 2: Mitosis Data
Chosen Image Onion Root Tip 100x image number 4
Stage Number of Cells in Total Number Calculated % of
Stage of Cells Time Spent in
Stage
Interphase 20 25 40%
Prophase 2 25 8%
