Cell Division Answer Key
Vocabulary: cell division, centriole, centromere, chromatid, chromatin, chromosome,
cytokinesis, DNA, interphase, mitosis
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
[Note: The purpose of these questions is to activate prior knowledge and get students thinking.
Students are not expected to know the answers to the Prior Knowledge Questions.]
1. Cells reproduce by splitting in half, a process called cell division. What do cells need to do
between divisions to make sure that they don’t just get smaller and smaller?
A cell must grow.
2. The genetic information of a cell is carried in its DNA (short for deoxyribonucleic acid). What
do cells need to do between divisions to make sure that a full set of DNA gets passed on to
each daughter cell?
The DNA must be copied so there is a full set of DNA to pass on to each daughter cell.
Gizmo Warm-up
On the SIMULATION pane of the Cell Division Gizmo™, check that
the Cycle Length is set to 12 hours. Click Play ( ), observe until
the maximum number of cells is shown, and then click Pause ( ).
1. Look at the cells. Do they all look the same? No
2. Cells that are in the process of dividing are said to be in mitosis
or cytokinesis. Cells that are not dividing are in interphase.
Check the Magnify box and move the cursor over the cells.
A. Of the 100 cells shown, how many are in the process of dividing?
Answers will vary (~5-20).
B. Select the BAR CHART tab, and turn on Show numerical values. How many cells
are in the interphase stage of their life cycle? Answers will vary (~80-95)).
C. Based on these two observations, would you say that a cell spends most of its life
cycle in interphase or in mitosis/cytokinesis? Interphase
This study source was downloaded by 100000830604181 from CourseHero.com on 02-07-2022 08:30:31 GMT -06:00
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, Get the Gizmo ready:
Activity A: Click Reset ( ).
Phases of the cell Select the DESCRIPTION tab.
cycle Click on the right arrow once so that Interphase is
shown.
Question: What are the stages of the cell cycle?
1. Observe: Click Play and hold the cursor over the cell. Observe the cell as it divides several
times. (This happens quickly!) What do you notice happening during this process?
Answers will vary. [Students may have noticed the material in the cell nucleus lining up and
then splitting apart as two cells form.]
2. Summarize: On the DESCRIPTION pane, read about each phase in the cell cycle. In the
spaces below, sketch the cell in each phase and summarize what occurs in your own words.
Answers will vary. Sample answers given below
Phase Sketch Summary
The cell grows, DNA is copied, and new organelles
Interphase
form.
Chromosomes are formed from chromatin, and the
Prophase nuclear membrane dissolves. Spindle fibers form
between the centrioles.
The centromere in each chromosome attaches to a
Metaphase spindle fiber, and the chromosomes form a line along
the middle of the cell.
The chromosomes split apart and the two sets of
Anaphase sister chromatids (daughter chromosomes) move to
opposite ends of the cell.
New nuclear membranes form around the two sets of
Telophase daughter chromosomes, which unwind into
chromatin.
The sides of the cell pinch inward, dividing the
Cytokinesis
cytoplasm and forming two daughter cells.
(Activity A continued on next page)
This study source was downloaded by 100000830604181 from CourseHero.com on 02-07-2022 08:30:31 GMT -06:00
https://www.coursehero.com/file/18329337/75/
Vocabulary: cell division, centriole, centromere, chromatid, chromatin, chromosome,
cytokinesis, DNA, interphase, mitosis
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
[Note: The purpose of these questions is to activate prior knowledge and get students thinking.
Students are not expected to know the answers to the Prior Knowledge Questions.]
1. Cells reproduce by splitting in half, a process called cell division. What do cells need to do
between divisions to make sure that they don’t just get smaller and smaller?
A cell must grow.
2. The genetic information of a cell is carried in its DNA (short for deoxyribonucleic acid). What
do cells need to do between divisions to make sure that a full set of DNA gets passed on to
each daughter cell?
The DNA must be copied so there is a full set of DNA to pass on to each daughter cell.
Gizmo Warm-up
On the SIMULATION pane of the Cell Division Gizmo™, check that
the Cycle Length is set to 12 hours. Click Play ( ), observe until
the maximum number of cells is shown, and then click Pause ( ).
1. Look at the cells. Do they all look the same? No
2. Cells that are in the process of dividing are said to be in mitosis
or cytokinesis. Cells that are not dividing are in interphase.
Check the Magnify box and move the cursor over the cells.
A. Of the 100 cells shown, how many are in the process of dividing?
Answers will vary (~5-20).
B. Select the BAR CHART tab, and turn on Show numerical values. How many cells
are in the interphase stage of their life cycle? Answers will vary (~80-95)).
C. Based on these two observations, would you say that a cell spends most of its life
cycle in interphase or in mitosis/cytokinesis? Interphase
This study source was downloaded by 100000830604181 from CourseHero.com on 02-07-2022 08:30:31 GMT -06:00
https://www.coursehero.com/file/18329337/75/
, Get the Gizmo ready:
Activity A: Click Reset ( ).
Phases of the cell Select the DESCRIPTION tab.
cycle Click on the right arrow once so that Interphase is
shown.
Question: What are the stages of the cell cycle?
1. Observe: Click Play and hold the cursor over the cell. Observe the cell as it divides several
times. (This happens quickly!) What do you notice happening during this process?
Answers will vary. [Students may have noticed the material in the cell nucleus lining up and
then splitting apart as two cells form.]
2. Summarize: On the DESCRIPTION pane, read about each phase in the cell cycle. In the
spaces below, sketch the cell in each phase and summarize what occurs in your own words.
Answers will vary. Sample answers given below
Phase Sketch Summary
The cell grows, DNA is copied, and new organelles
Interphase
form.
Chromosomes are formed from chromatin, and the
Prophase nuclear membrane dissolves. Spindle fibers form
between the centrioles.
The centromere in each chromosome attaches to a
Metaphase spindle fiber, and the chromosomes form a line along
the middle of the cell.
The chromosomes split apart and the two sets of
Anaphase sister chromatids (daughter chromosomes) move to
opposite ends of the cell.
New nuclear membranes form around the two sets of
Telophase daughter chromosomes, which unwind into
chromatin.
The sides of the cell pinch inward, dividing the
Cytokinesis
cytoplasm and forming two daughter cells.
(Activity A continued on next page)
This study source was downloaded by 100000830604181 from CourseHero.com on 02-07-2022 08:30:31 GMT -06:00
https://www.coursehero.com/file/18329337/75/
