Notes and Alternate Assessment: (Both must be completed for credit for this assessment. If the notes are not completed I will NOT grade or give you credit for the assignment.) This counts for both 3.02 and 3.03.

NOTES: Unit 3 Lesson 2: The Cell Cycle and Mitosis

Fill this in by attending or watching the 3.02 Live Lesson recording.

Parts of the Cell Cycle

  • Interphase:

G1 phase
S phase
G2 phase

  • Mitosis:

Prophase
Metaphase
Anaphase
Telophase

  • Cytokinesis
  • Interphase – (prepares for cell division)
  • Thelongest phase of the cell cycle
  • The cell is performing its job
  • DNA replicates
  • Chromosomes are not clearly visible
  • Three phases:
  • G1 phase – working and growing (longest)
  • S phase – DNA is duplicated
  • G2 phase – growing & storing energy, final prep for division
  • Mitosis (Cell Division) –
  • Prophase –
  • Nuclear membrane disappears
  • Spindle fibers form
  • Chromosomes become visible and begin to move
  • Additional vocab to review: chromatin, sister chromatids, centromere
  • Metaphase –
  • Sister chromatid pairs line up across the middle
  • Spindle fibers attach to center of each pair
  • Anaphase –
  • Paired chromosomes separate
  • Move to opposite sides of the cell
  • Telophase –
  • Nuclear membrane forms around each set of chromosomes
  • Cytokinesis:
  • The division of the cytoplasmand organelles
  • Shortest part of the cell cycle
  • Animal Cells – the cell membrane pulls inward and pinches in two
  • Plant Cells – a cell plate forms

BREAKOUT TIME!
If you want to use this as your collaboration that is OK! But FIRST, please check the bottom portion of your gradebook and see if you have ALREADY completed a collaboration. You will save us BOTH time by not submitting it if you already have collaboration credit.

Must have:

1. Partners’ Names: ______

2.Webmail me with Title: Mitosis Collaboration

3.Answers to questions 1 through 8.

Write the letter that matches the image to the Cell Cycle stage

1. C A. Interphase – longest stage, works, grows, copies DNA
2. F B. Prophase – chromosomes visible, membrane disappears
3. D C. Metaphase – line up at center
4. E D. Anaphase – pulled to opposite ends
5. B E. Telophase – 2 nuclei form
6. A F. Cytokinesis – splits in half, each with a nucleus and organelles

7. Use the graph

a) Which stage of the Cell Cycle has the greatest number of cells? Interphase

b) WHY are there more cells in this stage? It is the longest stage

8) You observe a cell with chromatid pairs lined up across the middle of the cell. What cell cycle stage comes next? Anaphase

What do I do now? (After the Live Lesson)

Watch this Crash Course video on Mitosis- 120247538

Notes: Unit 3 Lesson 3: Meiosis

Watch the recording and answer the following questions.

Recording: 120247538

Meiosis

Meiosis is involved in the formation of gamete production.

When you looked at the images of mitosis and meiosis, what are 2 differences you noticed?

a. They start off similar but when mitosis separates the cells meiosis creates two new cells b. In meiosis, after the two new cells are created, they are split a second time to create four daughter cells.

many daughter cells are produced?
the daughter cells genetically identical or different from the parent?
the daughter cells haploid or diploid? / Diploid Daughter- Haploid
Organism / Haploid (n) / Diploid (2n)
Amoeba
Fern
Hamster
Human
Onion

Complete the chart with the haploid/diploid #

Cells become haploid instead of diploid in telephase 1.

When chromatids of homologous chromosomes exchange corresponding segments during Prophase I it is called crossing over.

When chromosomes randomly lineup in the middle of a cell during Metaphase I it is called Independent Assortment.

Why is it important that cells produced after meiosis be diverse? So we can see the diversity in our population. If they were all the same our species would all die.

What do I do now?

Watch the Crash Course Meiosis video: 120247538 all

Alternate Assessment:

Part I: (3.02)

PROBLEM (Not to be answered at this stage in the lab): Which stage of the Cell Cycle has the greatest number of cells?

BACKGROUND INFORMATION: In this virtual lab activity, you will be observing the cell cycle in the tip of an onion root. The root tip is responsible for the downward growth of the root and is one of the regions in the plant where cells are actively dividing and growing. Because of this, the root tip is an excellent system in which to observe the entire cell cycle, including the processes of nuclear division (mitosis) and cell division (cytokinesis).

HYPOTHESIS (2 PTS):

If cells spend most of their time in interphase, then most of the cells I observe will be in interphase.

PROCEDURES/DATA (12 PTS): READ EACH STEP COMPLETELY BEFORE BEGINNING THAT STEP TO AVOID LOSING YOUR WORK!

1.Go to the Unit 3 Lesson 2 Cell Cycle and Mitosis lesson. Advance to page 5 (page 9 for Honors) and read the intro slide on the virtual lab.

2.Read through the information provided and roll over the images of the stages of the cell cycle for a brief overview of each phase.

3.When you start the virtual lab, you will look at 50 slides of onion root tip cells and identify the phase of the cell cycle that cell is currently in. After you choose the phase for the first 50 slides do NOT check your answer until you record your results on Table 1 below. IF YOU CHECK YOUR ANSWERS BEFORE RECORDING YOUR DATA BELOW YOU WILL HAVE TO REPEAT THIS PART OF THE ACTIVITY!

Table 1: Number of cells observed in each phase

INTERPHASE / PROPHASE / METAPHASE / ANAPHASE / TELOPHASE / CYTOKINESIS / TOTAL CELLS
34 / 8 / 3 / 2 / 2 / 1 / 50

4.Begin part of the virtual lab. This time you will view 76 slides. After you choose the phases for these slides do NOT check your answer until you record your results on Table 2 below. IF YOU CHECK YOUR ANSWERS BEFORE RECORDING YOUR DATA BELOW YOU WILL HAVE TO REPEAT THIS PART OF THE ACTIVITY!

Table 2: Number of cells observed in each phase

INTERPHASE / PROPHASE / METAPHASE / ANAPHASE / TELOPHASE / CYTOKINESIS / TOTAL CELLS
49 / 13 / 4 / 3 / 4 / 3 / 76

DATA ANALYSIS/CONCLUSION (20 PTS): Reflection questions need to be answered using complete sentences. Some questions may require a longer explanation in paragraph form. ALL answers need to include evidence from this activity and/or your notes packet.

1.(3pts) Calculate the percentage of the cells in each stage of the cell cycle and record on Table 3. HINT – (Number of cells in given stage ÷ total number of cells counted) × 100 = % of the cell cycle spent in this stage

Table 3: Percentage of Cells in each Phase

INTERPHASE / PROPHASE / METAPHASE / ANAPHASE / TELOPHASE / CYTOKINESIS / TOTAL %age
68.00% / 16.00% / 6.00% / 4.00% / 4.00% / 2.00% / 100%
64.40% / 17.10% / 5.20% / 6.00% / 5.20% / 6.00% / 100%

2.(2pt) Using your data from Table 3, what is the total percentage of cells found in mitosis?

28% and 33.5%

3.(2 pts) Based on your data, what can you infer about the length of time the cells spend in interphase compared to cellular division? Be sure to address specific numeric data in your answer.

I can infer that the cells spend way more time in interphase compared to cellular division. Cells spend more than half of their time in interphase than cellular division. In table one, cells spent 68% of the time in interphase and 28 percent of the time in mitosis. In table two, cells spent 64% of the time in interphase and 33.5% of the time in mitosis.

4.(2 pts) Why is the onion root tip a good specimen for studying mitosis?

Like it was stated at the top, the root tip is responsible for the downward growth of the root and is one of the regions in the plant where cells are actively dividing and growing. Because of this, the root tip is an excellent system in which to observe the entire cell cycle.

5.(2 pts) Imagine you are reading a book and get a paper cut on your pointer finger. Within two days the cut is completely healed and the skin has been repaired. Using your knowledge of the cell cycle, explain what was happening to the cells in the area surrounding the injury. Be sure to address specific stages of the cell cycle that would be occurring. USE COMPLETE SENTENCES.

Since the cells would be destroyed where I got the cut, my other cells would quickly begin to go in the interphase part of the cell cycle. The cells would spend lots of time in that phase but they would soon begin to go into mitosis and then cytokinesis and repair my skin.

Part II (3.03) The 3.03 Quiz has been dropped.

(15) points

Watch the recording below and use the information found there to answer the following questions about Meiosis.

ttps://sas.elluminate.com/p.jnlp?psid=2014-10-08.1829.M.5E7F1650D36702034CC394ED5BACE8.vcr&sid=679

6. ( 1 pt) Meiosis is involved in the formation of gamete production.

7.(2 pts) When you looked at the images of mitosis and meiosis, what are 2 differences you noticed?

a. They start off similar but when mitosis separates the cells meiosis creates two new cells b. In meiosis, after the two new cells are created, they are split a second time to create four daughter cells.

8. Complete the chart below: (6 pts)

many daughter cells are produced?
the daughter cells genetically identical or different from the parent?
the daughter cells haploid or diploid? / Diploid Daughter- Haploid

9. (1 pt)Which of the following best describes the process of meiosis?

a) It is the first stage of mitosis

b) It occurs in all tissues that require growth or replacement.

c) It happens in all cells except in the brain and nervous system.

d) It is carried out in cells that are involved in sexual reproduction.

Identify the statement as true of A. mitosis or B. meiosis (5 pts)

A 10. A type of cell division used for growth and repair

B 11. Creates haploid cells by separating homologous pairs

B 12. A type of cell division used for production of sex cells (gametes)

B 13. 2 divisions to create 4 genetically unique cells through crossing over and independent assortment

A 14. Creates diploid cells