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Unit 7L.1Specialized Cells
Name: Class: 7
animal
1 Al-Wakra Independent Preparatory School for Girls
What are cells?
Cells are the building blocks of life.
They come in all shapes and sizes.
Some organisms are made up of only one cell and are called uni-cellular.
Others are made up of lots of
cells and are called multi-cellular.
Cells work together and carry out the seven life processes that are needed for an organism to stay alive.
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plant cell
Animal and plant cells
Animal and plant cells come in different shapes
and sizes, but they all have three basic features.
animal cell
cytoplasm
cell membrane
nucleus
Plant cells also have some extra features that make them different to animal cells.3
Cell membrane
Cells & their Function
Controls what substances can get into and out of the cell.
Cytoplasm
Jelly-like substance, where chemical reactions happen. In plant cells there's a thin lining, whereas in animal cells most of the cell is cytoplasm.
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Controls what happens inside the cell - it is not a 'brain'.
Chloroplast
Where photosynthesis happens – chloroplasts contain a green substance called chlorophyll.
VacuoleContains a liquid called cell sap, which keeps the cell firm.
Nucleus
Cell wall Made of a tough substance called cellulose, which supports the cell.
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Compare a typical animal cell and a typical plant cell
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Which parts of a plant cell are the same as an animal cell?__________________________________________________
Which parts of a plant cell are not found in an animal cell? __________________________________________________
Specialized Cells
Function
Red blood cells
To carry oxygen
Special features
Large surface area, for oxygen to pass throughContains haemoglobin, which joins with oxygen
Nerve cell
To carry nerve impulses to different parts of the body
Function
Special features
Long Connections at each end Can carry electrical signals
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Male reproductive cell (sperm cell)
To reach female cell, and join with it
Long tail for swimmingHead for getting into the female cell
Function
Special features
To absorb water and minerals
Large surface area
Function
Special features
Root Hair Cell
Leaf Cell
To absorb sunlight for photosynthesis
Large surface areaLots of chloroplasts
Function
Special features9
Making a Slide of Onion Cell
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Building blocks of life - Cell-ebrate the Microscope
Cells could not have been discovered without the invention of the microscope.
“micro-” means” small”,“-scope” means “looking at”.
A microscope allows us to look at very small things by making them seem bigger. It magnifies tiny details and makes them visible to the human eye.
Making a Model of Animal or Plant Cell
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Name a cell that would be suitable for each job
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