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Cell
Biology |
Differences
between plant and animal cells:
- Size:
plant cells are usually larger and more regular in shape
- Cell wall:
Only present in plants
- Vacuole:
Plants have large vacuole present in central position
- Chloroplasts:
Only present in green cells of green plants
- Position
of nucleus: For plants, it presses to the periphery but for
animals, it lies in central
- Food
storage: Plants store starch and animals store glycogen mainly
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All living
organisms are composed of cells.
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Cells are the
basic unit of life.
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Cells can
generally be divided into 2 types: animal cells and plant cells.
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| Typical
plant cell
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Typical
animal cell
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Cell
membrane
- Encloses the
cytoplasm
- Living and
selectively permeable
- Thin and flexible and
made up of protein
- Function:
Regulates materials in and out of the cell
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Cytoplasm
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Contains dissolved
substances such as salts and sugars
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Contains organelles and
storage granules
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Jelly-like
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Function:
Site where most cellular activities are carried out. Also act
as storage function such as glycogen in animal and starch in plants.
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Nucleus
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Spherical
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One per living cell
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May be absent in some
animal cells such as mature red blood cell
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Contains chromatin
surrounded by nuclear membrane
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Function:
Controls cellular activities and contains genetic materials in the
form of chromosomes.
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Vacuole
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A membrabe-bound sac
containing cell sap, a clear liquid
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Large and occupies a
central position in plants and small or absent in animals
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Function:
Stores dissolved substances such as food and waste, give
turgidity for support in young plants
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Cell
wall
- Present in plant
cells only
- A cellulose,
non-living rigid layer
- Freely permeable
- Function:
Maintain the plant's shape, protect inner organelles
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Chloroplast
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Present in plant cells
only
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Contains photosynthetic
pigments called chlorophyll
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Function:
Site at which photosynthesis takes place
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