biology cell cell the basic unit of structure and function in living organisms. the basic unit of...
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BiologyBiology
CELLCELL
The basic unit of The basic unit of structure and function structure and function in living organisms.in living organisms.
Extremely smallExtremely small can be seen properly can be seen properly
only when magnified only when magnified and viewed through and viewed through microscope.microscope.
CELLCELL
Your body has about Your body has about 50 billion cells; some 50 billion cells; some microscopic microscopic organisms only have organisms only have one cell, e.g. amoeba.one cell, e.g. amoeba.
The structure of a typical plant cellThe structure of a typical plant cell
cell wall
cell membrane
vacuolecytoplasm
nucleus
chloroplast
Non-living granules
Cell WallCell Wall
Found in Found in plant cellsplant cells only. only. Made of cellulose fibre.Made of cellulose fibre. Freely permeable.Freely permeable.
Functions : Functions :
a/ To protect and support the enclosed protoplasm.a/ To protect and support the enclosed protoplasm.
b/ To resist the entry of excess water into the cell.b/ To resist the entry of excess water into the cell.
Cell membrane / Plasma membraneCell membrane / Plasma membrane
All cells are surrounded by cell membrane.All cells are surrounded by cell membrane. It is very thin.It is very thin. It is selectively permeable.It is selectively permeable.
Function:Function:
To control the passage of materials in and out of To control the passage of materials in and out of the cellthe cell..
CytoplasmCytoplasm
A clear, jelly like substance enclosed by the cell A clear, jelly like substance enclosed by the cell membrane.membrane.
It consists of an aqueous solution with proteins.It consists of an aqueous solution with proteins.
Function:Function:
a/ A medium for chemical reactions to take place.a/ A medium for chemical reactions to take place.
b/ To hold the organelles and granules.b/ To hold the organelles and granules.
OrganellesOrganellesChloroplastsChloroplasts
Present in green plant Present in green plant cells cells
Contains the green Contains the green pigment chlorophyllpigment chlorophyll
Function:Function:
The site of The site of photosynthesis.photosynthesis.
OrganellesOrganellesMitochondriaMitochondria
Present in all living cells.Present in all living cells. Appear as rod-shaped or Appear as rod-shaped or
cylindrical organelles.cylindrical organelles. Cellular respiration takes Cellular respiration takes
place there and food is place there and food is oxidized to release energy.oxidized to release energy.
Also known as the ‘Power Also known as the ‘Power House’.House’.
Function:Function: Site of respiration.Site of respiration.
GranulesGranules
Crystals of insoluble Crystals of insoluble waste.waste.
Starch granules in the Starch granules in the cytoplasm as food cytoplasm as food reserve in plant cells.reserve in plant cells.
VacuoleVacuole
Fluid-filled cavities Fluid-filled cavities bounded by a membrane bounded by a membrane called called tonoplasttonoplast..
Contains a solution of Contains a solution of sugars, protein and mineral sugars, protein and mineral salts called salts called cell sapcell sap..
The vacuoles of animal The vacuoles of animal cells are usually very small.cells are usually very small.
vacuole
NucleusNucleus
Contains genes (carry Contains genes (carry the genetic information).the genetic information).
Genes are made up of Genes are made up of DNA and they are DNA and they are located on the located on the chromatin/chromosomeschromatin/chromosomes..
NucleusNucleus
Function:Function:
a/ controls the activities a/ controls the activities
of the cell.of the cell.
b/ transmits genetic b/ transmits genetic
information to the information to the
next generation.next generation.
Basic structure of animal cellBasic structure of animal cell
mitochondrion
nucleusnucleolus
nuclear membrane
cytoplasm
vacuole
cell membrane
Animal CellsAnimal Cells
Animal cells do not have Animal cells do not have cell wall and chloroplast.cell wall and chloroplast.
The vacuole in animal cells The vacuole in animal cells are usually small.are usually small.
Non-living granules are Non-living granules are usually glycogen or oil usually glycogen or oil droplets.droplets.
There is a greater variety of There is a greater variety of animal cells than the plant animal cells than the plant cells.cells.
Similarities between animal and Similarities between animal and plant cellsplant cells
Both have:Both have:
nucleusnucleus cytoplasmcytoplasm
mitochondrionmitochondrion chloroplastchloroplast
cell wallcell wall cell membranecell membrane
Differences in Animal and Differences in Animal and Plant CellsPlant Cells
Plant Cell Animal Cell With cell wall Without cell wall With chloroplast Without chloroplast Large vacuole at the central
Vacuoles are small or absent
Starch granules as food reserve
Glycogen granules as food reserve
Usually larger in size and regular in shape
Usually smaller in size and irregular in shape
Nucleus found just beneath the cell wall
Nucleus found in the center of the cell
Can you distinguishCan you distinguish plant cells and animal cells from plant cells and animal cells from
the following pictures?the following pictures?
Plant cells Animal cells
Can you distinguishCan you distinguish plant cells and animal cells from plant cells and animal cells from
the following pictures?the following pictures?
Animal cells Plant cells
WEBWEB SITESSITES
http://library.thinkquest.org/3564/
http://www.kapili.com/biology4kids/cell
http://personal.tmlp.com/Jimr57/tour/cell/
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