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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