1. LESSON PLAN IN SCIENCE (GRADE 8)
Teacher: Frederick E. Macaso Date:_____________
Subject area:Science – Living things and Environment Grade Level: Grade 8
Topic: The cell cycle- Mitosis Time:__________
CONCEPTS
Cell cycle has three stages: Interphase, mitosis and cytokinesis
Interphase has three parts: G1 or Gap 1 phase, S phase or synthesis phase and
G2 phase or Gap 2 phase.
Mitosis has 4 phases: Prophase, Metaphase, Anaphase and Telophase.
Cytokinesis is the division of cytoplasm to form two daughter cells immediately
after mitosis.
OBJECTIVES
Given a pictures/diagrams of cell cycle, the grade 8 students can do the following
with at least 75% of proficiency, within 60 minute class period:
a. Analyze the three stages of cell cycle
b. Identify the different stages of mitosis and;
c. State the importance of mitosis in cells
CONTENT STANDARD/S
The learner demonstrate an understanding of
a. How cells divide to produce new cells.
LESSON PROPER
Prerequisite: Chromosomes; sister chromatids
Materials: Diagrams of the cell cycle
Diagrams of the different stages of mitosis
Mitosis phase worksheets
Procedure: 5E’s
TEACHER’S ACTIVITY STUDENT’S ACTIVITY
ENGAGE
(Shows a picture of Naruto doing the Kage
Bushin Technique- or the shadow clone of
ninja)
Are you familiar with this picture? Who is
in the picture?
Naruto! Doing the kage bushin technique
As you’ve observed, he replicated himself
many times. Can you do the same?
No.
Well, off course not, but do you know
something that can clone themselves?
Cells (answers may vary)
Very good! Every single one of them
clones or multiplies by themselves and in
fact, they’re doing it right now.
From single cell organism to bigger
creature, all of them stems from cell’s
ability to reproduce themselves.
2. Why do you think reproduction of cells in
our body is essential or important?
Because, that’s what allows organism to
grow, heal, develop and keep from dying
for as long as possible.
What do we call this kind of cell division? Mitosis.
That’s right. Did you know that mitosis is
responsible for a whole lot of your body’s
key functions?
If you get a cut, you body needs to
produce new cells. That’s mitosis!
Have too much to drink and damage your
liver? You got to replace those cells.
That’s mitosis.
Tumor growing in your brain?
Unfortunately, again, mitosis!
When you go from 7 pound baby and now,
you’re 100 pound, it’s not your cells that
are increasing in mass, but you’re just
getting more of them over and over again!
So you are made up of cells just like the
elephant and the trees. Do you still
remember the three major parts of the
cell?
Nuclear membrane, Cytoplasm and the
nucleus
That’s right! Now what is the function of
nucleus?
Nucleus stores DNA.
And what is DNA and what does it do? It contains all the instructions on how to
build organisms.
(post the diagram of the organization of
the DNA)
As you can see, DNA is organized as
beads and strings to form chromosomes.
Now do you remember how many
chromosomes do you have in each cell?
46 chromosomes or 23 pairs of
chromosomes
-half comes from your father and the other
half, from your mother.
During mitosis, the cell with 46
chromosomes to split into two cells, that
are genetically identical.
Since the nucleus has all the necessary
instruction for the cell to survive, we don’t
need to duplicate the whole cell. Instead,
mitosis, is simply duplicating the DNA that
is stored in the nucleus.
EXPLORE
Now we are going to find out how mitosis
takes place by doing the following activity.
But first let me introduce you the CELL
CYCLE. (post the cell cycle diagram on
the board)
As you can see, obviously, it’s a cycle of a
cell. How many phases does a cell cycle
have? And what are they?
Three! Interphase, Mitotic Phase and
Cytokinesis.
All right! Now the Interphase, as you can
see, are divided into 3 sub phases, which
are the G1 or what we called the Gap 1,
The S phase or the synthesis phase and
the G2 or the Gap 2 phase.
What do you think is happening to the cell
during G1 phase?
Cell grows initially
That’s right! How about in the S phase? DNA replicates into sister chromatids
3. And the G2? The cell rapidly grows and prepares for the
cell division!
That’s right! And how does division takes
place? You discover it by yourselves.
(Distributes the activity sheets)
Who can read the instructions? Student reads the instructions
You only have 10 minutes (or less) to
finish the activity
If you have any questions, please raise
your hand.
EXPLAIN
Which picture best describes interphase? Letter D
What do you think is happening during
interphase?
Cell duplicates, cell grows
Which picture best describes prophase? Letter C
Why do you think its letter c? Because chromosomes are starting to get
visible like long threads; network of spindle
fibers starting to form.
Very good! Now how about pro-
metaphase?
Letter f!
Why do you think it’s letter f? Because the chromosomes starts to move
towards the middle or equator of the cell.
Good, no how about metaphase? Letter B!
Why? The chromosomes lined up at the equator
of the cell.
Great! What picture best describes
anaphase?
Centromeres divide and chromosomes
move toward opposite poles of the cell.
How about the telophase? Letter A
Why do you think its letter A? Chromosomes decondense;
chromosomes have reached the opposite
poles of the cell.
And lastly, the cytokinesis? Letter A!
Correct! It’s also letter A! why do you think
so?
Cleavage furrow starts to form at the
equator of the cell.
Why is it essential part of the cell cycle? Because it is the process where cytoplasm
divides into two.
Very good! And the result as you can see,
from one cell to two daughter cell, hence,
cell division.
ELABORATE
Now, we already know how cell duplicates
itself. Why do you think mitosis is very
important?
It’s important because it’s responsible for
the growth, repair and development of our
cell and all the key functions of the cell.
Correct, so, when we get a cut, as what
I’ve mentioned earlier, it’s the job of the
mitosis to replace or repair the damage
tissues.
Now, cancers or tumors are also caused
by mitosis, what might be the cause?
It’s because of the some cells escapes
from cell cycle regulation and divides
uncontrollably.
That’s right you will learn more about
these in your higher grades.
EVALUATION
4. DIRECTION: Choose the letter of the correct answer.
1. The following are the major phases/stages of the cell cycle, except
a. Cytokinesis
b. Interphase
c. Mitotic phase
d. None of the above
2. Phase of mitosis where chromosomes are aligned in the middle or equator of the
cell.
a. Interphase
b. Prophase
c. Metaphase
d. Telophase
3. What is the major function of mitosis?
a. To make the cell bigger in mass
b. To protect the cell from foreign materials
c. To produce two cells
d. To nourish the cell
4. How many chromosomes does a human have?
a. 23
b. 46
c. 56
d. 43
5. It is the phase of the cell cycle where chromosomes are being duplicated.
a. G1 phase
b. S phase
c. G2 phase
d. Cytokinesis
6. What causes cancer?
a. When the cell fails to divide
b. When the chromosomes are not in pairs
c. When the nucleus die.
d. When cell divides abnormally or uncontrollably.
7. What is happening during telophase?
a. The chromosomes reached the opposite ends of the cell.
b. The spindle fibers start to form.
c. The cell starts to grow and prepare for division
d. The chromosomes form into sister chromatids.
8. Arrange the steps or stages of cell cycle in order
a. G1 phase- S phase- G2 phase- Prophase- Anaphase - Metaphase-
Telophase- Cytokinesis
b. G1 phase-S phase-G2 phase- - Prophase- Metaphase- Anaphase-
Cytokinesis- Telophase
c. G1 phase-S phase-G2 phase - Prophase- -Metaphase- Anaphase -
Telophase- Cytokinesis
d. G1 phase-S phase-G2 phase - Prophase- Metaphase- Telophase- Anaphase
–Cytokinesis
9-10. Give briefly descriptions of each of the phases of cell cycle that will distinguish it
from the other.
Interphase: __________________
Mitotic Phase: ________________
Cytokinesis: __________________
Assignment:
1. Read about Meiosis.
2. What is the major difference between mitosis and meiosis?
3. What is the importance of meiosis?
