The Cell

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Identifying Cells under the Microscope
Science 8: Cells, Tissues, Organs, and Organ Systems
Curriculum Outcomes Addressed:
• Illustrate and explain that the cell is a living system that exhibits all of the characteristics of life (304-4)
• Distinguish between plant and animal cells (304-5)
• Explain that it is important to use proper terms when comparing plant and animal cells (109-13)
The word cell comes from the Latin
word cella, which means "small room“.
http://us.123rf.com/400wm/400/400/eraxion/eraxion1006/eraxion100600408/7149016-human-cells.jpg
Review: Characteristics of Living Things
The cell theory consists of six characteristics of living things.
Anything that has all six of these characteristics is classified
as a living thing.
1. Living things are composed of ___________
2. Living things reproduce, grow, and ________ themselves
3. Living things require ____________
4. Living things respond to the ______________
5. Living things have a ________________
6. Living things produce ______________
Review: Characteristics of Living Things
The cell theory consists of six characteristics of living things.
Anything that has all six of these characteristics is classified
as a living thing.
1. Living things are composed of cells
2. Living things reproduce, grow, and repair themselves
3. Living things require energy
4. Living things respond to the environment
5. Living things have a life span
6. Living things produce wastes
During this lesson, we will…
– Learn about the differences between plant and animal
cells in more detail (cell size, shape, and organelles)
– View examples of plant and animal cells and their
organelles when magnified under a microscope
– Practice identifying microscopic images of plant and
animal cells
– Continue to become familiar with the terminology used
when talking/writing about cells and their organelles
Plant vs. Animal Cells
• There are a number of differences between plant
and animal cells that can be seen when they are
viewed under a microscope
• Can you think of any?
Plant vs. Animal Cells
• There are a number of differences between plant
and animal cells when they are viewed under a
microscope
– Cell size and shape of animal and plant cells differ
– Some organelles are found only in one cell type, but
not in both (cell wall and chloroplast in plant cells;
flagellum and cilia in animal cells)
– Some shared organelles have different sizes and
numbers in plant cells compared to animal cells
Plant vs. Animal Cells under the Microscope
There are some visual differences between cell types…
Plant Cells
Animal Cells
Cell Size
Large; usually visible under Smaller than plant cells;
40X magnification
usually visible under 100X
magnification or greater
Cell Shape Rectangular; more defined Circular; less defined
Vacuoles Usually have one very
Usually have a number of
large central vacuole; the smaller vacuoles spread
vacuole can take up almost throughout cytoplasm;
90% of the plant cell
store water, minerals, and
volume; stores water
waste materials
Cell size and shape differences between plant and animal cells
- Plant cells are usually larger than animal cells
- Plant cells are rectangular; animal cells are circular
Plant cell at 400X magnification
Animal cell at 400X magnification
(Frog blood cells – stained purple)
•
http://www.danacode.co.il/thecel/cel1/ELODIA400.jpg
Organelle differences between plant and animal cells
Plant cell at 400X magnification
- Large central vacuole
- Chloroplast
- Thick outer cell wall
Animal cell at 1000X magnification
- Smaller vacuoles throughout
- No chloroplast
- No thick outer cell wall
•
http://www.franklin.k12.ma.us/~allenc/014E2A6A-0066418D.16/vacuole--plant0.jpg
http://ars.els-cdn.com/content/image/1-s2.0-S1434461011001258-gr14.jpg
Plant vs. Animal Cells
Some organelles are not found in both types of cells…
Organelle
Type of Cell found in and explanation
Some organelles are not found in both types of cells
Organelle
Type of cell found in and explanation
Found only in plant cells; the cell wall is the thick
Cell Wall outermost layer of plant cells. It supports and
protects the cell. It is very rigid, so it does not allow
the plant cell to expand or adapt as much as the
animal cell is able to.
Found only in plant cells; it contains chlorophyll,
Chloroplast which is responsible for converting Carbon dioxide
and water into sugar molecules (energy/food) during
photosynthesis. Animals cannot make their own food.
Chlorophyll is a pigment that gives plants their green
colour.
Found only in some animal cells (but not in plant
Flagellum/ cells). These are whip-like and hair-like structures
Cilia
which help the cell to move
Organelles Under the Microscope
Mitochondrion
Nucleus, Nucleolus, and Chromosomes
http://biology.unm.edu/ccouncil/Biology_124/Images/mitochondria.bmp
Rough and Smooth Endoplasmic Reticulum
http://iws.collin.edu/biopage/faculty/mcculloch/1406/outlines/chapter%207/animalcell2.jpg
Golgi Body and Lysosomes
http://faculty.une.edu/com/abell/histo/golgilys.jpg
http://www.zoology.ubc.ca/~berger/b200sample/unit_8_protein_processing/images_unit8/0_300_er.jpg
Helpful Resources
• Interactive 3D Cell and Organelles:
http://www.cellsalive.com/cells/3dcell.htm
• Differences between Plant and Animal Cells in more detail:
http://www.diffen.com/difference/Animal_Cell_vs_Plant_Cell
• Cell Structures and Functions (detailed presentation):
http://www2.hoover.k12.al.us/schools/hhsfc/teachers/dwalker/Documents/Cell
%20Organelles.pdf
• Plant and Animal Cell Online Practice Quiz:
http://www.quizrevolution.com/ch/a70678/go/plant_and_animal_cells_quiz
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