Name: _________________________________________________________________

Unit 3: Inheritance & VariationCell Division & Mitosis (CH. 8)

Objective: _______________________________________________________________________________________________________________________________________________

NGSS Standard: LS 1-4Use a model to illustrate the role of cellular division (mitosis) and differentiation in producing and maintaining complex organisms.

1. In a healthy body, cell division allows for ________________________________, the replacement of ____________________________________cells, and development from an embryo into an adult.In sexually reproducing organisms, __________________and _______________________ result from mitosis and meiosis.

CELL DIVISION AND REPRODUCTION2. Organisms reproduce their own kind, a key characteristic of life.

Cell _______________________ is reproduction at the cellular level, requires the ________________ of chromosomes, and sorts new sets of chromosomes into the resulting pair of _______________cells.

3. _____________________________ of a prokaryote occurs in three stages: duplication of the chromosome and separation of the copies, continued elongation of the cell and movement of the copies, and division into two daughter cells.

THE EUKARYOTIC CELL CYCLE AND MITOSIS4. Eukaryotic chromosomes are composed of _____________________

consisting of one long DNA molecule._________________________ proteins that help maintain the chromosome structure and control the activity of its genes.To prepare for division, the chromatin becomes highly ____________visible with a microscope.

5. Before a eukaryotic cell begins to divide, it duplicates all of its chromosomes, resulting in two copies called ___________________ and joined together by a narrowed “waist” called the ______________.When a cell divides, the sister chromatids separate from each other, now called ____________________________, and sort into separate daughter cells.

6. LABEL:

7. Mitosis progresses through a series of stages: prophase (prometaphase), metaphase, anaphase, and telophase. Cytokinesis often overlaps telophase.

8. Interphase The cytoplasmic contents ___________________ chromosomes ____________________________ in the nucleus during the S phase

9. Prophase chromosomes coil and become _______________ nucleoli ___________________________________

10. Metaphase Chromosomes align at the cell

_________________________________.11. Anaphase

________________________________ds separate at the centromeres. Daughter chromosomes are moved to

______________________________poles of the cell12. Telophase

The cell continues to _______________________________. Two daughter _____________________________________ begin to form. Chromatin _____________________________ The spindle _____________________________

13. During cytokinesis, the __________________________ is divided into separate cells.

The process of cytokinesis differs in animal and plant cells.14. In animal cells, cytokinesis occurs as a ___________________________ forms from a contracting ring

of microfilaments and interacting with myosin.

15. In plant cells, cytokinesis occurs as a _________________________ forms in the middle from vesicles containing cell wall material.

Anchorage, cell density, and chemical growth factors affect cell division16. The cells within an organism’s body divide and develop at different rates.

Cell division is controlled by the presence of essential

_______________________________________, _________________________________, proteins that stimulate

division, _________________________________, in which crowded cells

stop dividing, _________________________________, the need for cells to be in

contact with a solid surface to divide.

17. There are three major checkpoints in the cell cycle. G1 checkpoint

allows entry into the ______________________ or causes the cell to leave the cycle, entering a nondividing ____________ phase.

G2 checkpoint M checkpoint.

Research on the __________________________________ is one of the current areas highly studied in biology today.

CONNECTION: Growing out of control, cancer cells produce malignant tumors18. Cancer currently claims the lives of _______________________________ of the people in the United

States and other industrialized nations.19. Cancer cells

divide rapidly, often in the _______________________________, spread to other tissues through the __________________________ system grow _________________________________________________ by other cells.

20. A ________________________is an abnormally growing mass of body cells. Benign tumors remain at the original site. Malignant tumors spread to other locations, called metastasis.

LABEL

21. Cancers are named according to the organ or tissue in which they originate. Carcinomas arise in external or internal _______________________________. Sarcomas arise in __________________________________________________ tissue. Leukemias and lymphomas arise from _________________________________ tissues.

22. Cancer treatments Localized tumors can be removed ______________________________ and/or treated with

concentrated beams of high-energy __________________________________. __________________________________________is used for metastatic tumors.

TARGETS1. Explain why cell division is essential for prokaryotic and eukaryotic life.

2. Describe the stages of the cell cycle.

3. Describe the functions of mitosis and the events of each phase.

4. Compare cytokinesis in animal and plant cells.

5. Explain how anchorage, cell density, and chemical growth factors control cell division.

6. Explain how cancerous cells are different from healthy cells.

NEXT QUESTIONS If all cells have the same DNA, how do we get different cells to create different tissues? If all cells have the same DNA, how do cells form new organisms with a combination of mother and

father DNA?REVIEW

For each statement below, choose either Agree or Disagree. If the statement is true, give an example or a connection to your life. If you disagree, reword the statement to make it valid.

Statement Agree or Disagree? If agree: Example or connectionIf disagree: Reworded to make it valid

Cell division does not involve DNA.

Cytokinesis is the second part of cell division.

Only eukaryotic cells undergo cell division.

Binary fission is a type of cell division.

Complete the diagram below to show cell division. Write the name of one event in each circle along with a brief explanation of each. Place the first event in the top circle.

Event Bank: Separation, DNA Replication, Chromosome Segregation, cytoplasm splits and two daughter cell form, chromosomes move to opposite sides of the cell., DNA is copied

1. Conclude why it is necessary for chromatin to condense before cell division takes place? Explain and justify your answer with evidence.

2. Based on what you know, how would you explain why some cells have a shorter cell cycle than others.

3. Explain and justify why interphase consumes the majority of time in a cell cycle.

4. Distinguish between the first phase, prophase, with the final phase of mitosis, telophase?

5. What is one distinguishing difference in plant cell mitosis when compared to animal cell mitosis?

KEYDNA Replication- DNA is copied

1. (Evaluation) Conclude why it is necessary for chromatin to condense before cell division takes place? Explain and justify your answer.Chromatin in its tangled, elongated form would easily break if not condensed during mitosis, as the spindle pulls the chromosomes to opposite ends of the cell.

2. (Evaluation) Based on what you know, how would you explain why some cells have a shorter cell cycle than others.Some cells undergo more wear and tear in the body, such as those in the digestive tract. These cells need to constantly be replaced to maintain function in the body.

3. (Evaluation) Explain and justify why interphase consumes the majority of time in a cell cycle.During interphase the cell needs time to grow and provide the necessary components, including organelles to create two new daughter cells. Chromosomes are duplicated during this phase as well.

4. (Synthesis) Where are the chromosomes located in the cell during each of the four different phases of mitosis? Create a pictograph from the written description in your book, using the given materials on your desk. (Oreos and sprinkles)Students should indicate the chromosomes first being within the nucleus, then lined up in the middle of the cell. The third drawing should show the chromosomes being pulled toward opposite ends of the cell, then surrounded by two separate nuclear envelopes.

5. (Analysis) Distinguish between the first phase, prophase, with the final phase of mitosis, telophase?During prophase, the nuclear envelope breaks apart and disintegrates from around the newly coiled and replicated chromosomes and the centrioles move toward opposite ends of the cell. At the end of mitotic phases, the new nuclear membranes develop around the nuclei, the chromosomes uncoil and become tangled, elongated masses of chromatin, and the centrioles move close to the new nuclei.

6. (Analysis) What is one distinguishing difference in plant cell mitosis when compared to animal cell mitosis?Plants do not go through the process of cleavage in the cell membrane as animal cells do. They develop a cell plate structure down the middle of the two new cells. A new cell membrane then forms around each cell. Plants have asters, rather than centrioles, that hold the mitotic spindle in place.