Cell variety in relation to function
The cell is the basic unit of life.
All living things are made up of cells.
Draw and label a typical animal cell and a typical plant cell.
Generalised animal cell
Generalised plant cell
Construct a table to show which structures are found in each of the above cells and their
function.
As we investigate the cellular processes needed for life, we will become aware of other
structures within cells which are often too small to be seen with a light microscope.
These organelles make up the cell’s ultrastructure.
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Unicellular organisms
Some organisms exist as single cells (unicellular) and carry out all the functions needed for the
continuation of life within one cell. eg Amoeba exist as single cells and reproduce by binary
fission (mitosis) when they reach a critical size. (Standard Grade)
Draw and label the following unicellular organisms and briefly describe the habitat of each:
Unicellular animal - Paramecium
Unicellular plant – Pleurococcus
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Multicellular organisms
Complex animals and plants may consist of many millions of cells organised into tissues. A
tissue is a group of cells specialised to perform a particular function. At this multicellular level of
organisation, there is division of labour (all of the cells need not carry out all of the functions
necessary to sustain life).
Cell variety in multicellular organisms
The structure of a cell (what it looks like and what it contains) is related to its function (what it
does). Once a new cell has been formed (by cell division), it becomes specialised with regard to
its shape, size and chemical ‘machinery’ to enable it to carry out its particular role.
In the space below draw out 3 cells from a human and add a label to describe; tissue / cell
type / specialised structural features and function.
In the space below draw out 3 cells from a human and add a label to describe; tissue / cell
type / specialised structural features and function.
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Variation within one tissue
Some tissues are made up of only one type of cell eg smooth muscle.
However, some tissues contain a variety
of cell types working together.
eg phloem
Variation between different tissues
Variation in cell structure can be very apparent when different types of tissue are compared.
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