Cell Structure, Mitosis and Meiosis
Grade Level: 9-12 Grade
Title: Cell Structure,
Mitosis, Meiosis & DNA
Sunshine State Standards:
SC.F.1.4 The student describes
patterns of structure and function in living things.
SC.H.1.4 The student uses
the scientific processes and habits of mind to solve problems.
SC.H.2.4 The student understands
that most natural events occur in comprehensible, consistent patterns.
Unit: Biology of the Cell,
It is important that students
know that all living organisms are composed of cells, which is the beginning
of life. We will focus on eukaryotic cells, classifying them into
plant and animal cells. Students should know the parts of eukaryotic cells
to understand and assess the importance of reproduction and photosynthesis.
9th – 12th grade science
students will identify the basic parts of plant and animal cells using
the chart in their book and pictures/slides to distinguish their differences.
Each student will be able to label plant and animal cells with 100% accuracy.
Students will also be able to understand the importance of DNA, Mitosis
and Meiosis, and how they are involved in the reproduction process.
1. Eukaryotic Cell
– Literally "true nucleus". The term applies to all protists, plants,
animals, and fungi. Eukaryotic cells have internal membranes that partition
them into regions for different functions, such as mitochondria, plastids,
the ER, Golgi apparatus, etc. They also possess a cytoskeleton that helps
them control their shape.
2. Animal Cell-
contain parts that are listed on chart below.
3. Plant Cell- contain
parts that are listed on the chart below.
4. Meiosis- (my-oh’sis)
Process in which a 2n cell undergoes two successive nuclear divisions (meiosis
I and meiosis II), potentially producing four n nuclei; leads to the formation
of gametes in animals and spores in plants; division of cells during sexual
(my-toh’sis) Division of the cell nucleus, resulting in two daughter nuclei,
each with the same number of chromosomes as parent nucleus. Mitosis consists
of four phases: prophase, metaphase, anaphase, and telophase. Cytokinesis
(division of the cytoplasm to form two separate cells) usually overlaps
the telophase stage. This process is the division of body (somatic) cells
6. DNA- Deoxyribonucleic
acid. The genetic material of all organisms; composed of two complementary
chains of nucleotides wound in a double helix. Chromosomes contain the
genetic information that dictates what characteristics the daughter cells
will possess. It is useful to visualize a chromosome as a continuous
strand of DNA. Arrayed along the DNA strand are the genes, specific
regions whose sequences carry the genetic code for making specific proteins.
Ø Anticipatory Set:
By a show of hands, who
knows the difference between plant and animal cells? Who can explain
the difference between Mitosis and Meiosis? What is the purpose of DNA
in the nucleus?
Tell the students that
today’s lesson is to help them understand the contents of plant and animal
cells. They will have basic knowledge regarding phases of Mitosis and Meiosis,
and what an important role DNA plays in the reproduction of living things.
Show plant and animal cell
transparencies. Explain that both types, although similar, contain
certain different parts. Show the phases of Mitosis and Meiosis using
visual aids. Show the DNA phases and explain how each step is important
||May be present
||Absent except in sperm of a few species
||Multiple; DNA-protein complex
||Multiple; DNA-protein complex
||Present as "spherosomes"
||Absent or small
||Usually a large single vacuole
Major differences between mitosis and meiosis.
1. Number of cell divisions and products.
mitosis - one cell division resulting in two daughter cells
meiosis - two cell divisions resulting in four products of meiosis
2. Ploidy (# chromosome sets) per nucleus.
mitosis - 2N to 2N
meiosis - 2N to N to N
3. Synapsis of homologous chromosomes.
mitosis - no pairing
meiosis - pairing at zygotene of prophase I
4. Exchange of genetic material between synapsed
mitosis - does not occur
meiosis - occurs at pachytene of prophase I (first visible at diplotene)
5. Timing of division of centromeres.
mitosis - occurs at anaphase
meiosis - occurs at anaphase II but not at anaphase I
6. Genetic variation.
mitosis - conservative process; does not lead to genetic variation
meiosis - leads to increased genetic variation following recombination
Ø Check for Understanding:
Ask students: Do plant cells
contain centrioles, and what significant role do they play within the cell?
Do animal cells contain chloroplasts? Which type of cell has a cell wall?
What three parts of a plant cell are not parts of an animal cell? Is Mitosis
and Meiosis the same thing? How are they different? Who knows
the phases of mitosis? What are chromosomes and what part do
they play within the cell? What are amino acids and why are they
significant in a DNA strand? Why is the understanding of chemistry
an important part of biology?
Ø Guided Practice:
Tell students that the list
of plant and animal cells shows the contents of each cell. Plant and animal
cells have many of the same features, called organelles. These organelles
are the basis of cell functions. However, plant cells have three major
organelles of which animal cells do not, chloroplasts (carry chlorophyll),
a cell wall (cellulose), and a large central vacuole (storage).
Mitosis is the process
for cell division for body cell reproduction whereas Meiosis is the process
of cell division for sexual reproduction. All cells contain DNA, prokaryotic
and eukaryotic, as well as viruses. The process of translation and transcription
are characteristics of DNA.
Ó Use diagram of
cell to identify and label both types of cells.
Ó Review cell organelles
on overhead projector.
Ó Use diagram of
mitosis and meiosis to understand how cells divide and create daughter
Ó Study the process
of DNA and its significance within the cell.
Ó Create model of
mitosis and DNA strand.
Ø Independent Practice:
Students are to name and
select the correct organelle magnets placing them on the proper cell (animal
or plant) on the board. Give students enough time to complete this task.
Worksheets on mitosis, meiosis, and DNA structure will be distributed to
each student to test for knowledge and comprehension of cell division and
Materials & Resources:
Plant and animal cell worksheet,
Mitosis & Meiosis worksheet, DNA diagram and worksheet, transparencies,
Biology textbooks: Raven
Johnson 5e, Holt.
(3) Low Level:
1. Knowledge- List
the organelles of an eukaryotic cell.
Determine what organelles belong to the plant and animal cell.
Construct a brief diagram of the phases of meiosis.
(3) High Level:
Relate meiosis to mitosis and distinguish the similarities and differences.
5. Synthesis- How
would you create your own diagram of DNA?
6. Evaluation- Assess
the process of cell division and reproduction.
After the review of eukaryotic
cells, the students will be able to identify and name the organelles of
plant and animal cells correctly. Each student will have a basic
knowledge and comprehension of cell division and reproduction through their
study of mitosis and meiosis. Students will have an understanding of DNA
within eukaryotic cells. They will create a model of a DNA strand and assess
how it plays a role in reproduction.