To make models of plant and animal cells using gelatine.
Materials per model of plant cell and animal cell.
2 Plastic containers, one with lid e.g.
Materials to represent cell organelles e.g.
sandwich boxes. (A smaller container could modelling clay, sweets e.g. coloured jellies,
be used to represent the animal cell)
fruits, seeds etc.
Large beaker
Gelatine
Stirring rod.
Hot water
Mounted needle
Small plastic bag
Flag labels
Procedure
The models may be made over 3 days (stages A,B,C below) but only allowing a short
time for the activity at each stage.
A.
1. Line 2 plastic sandwich boxes with cling film and leave enough extra cling-film
attached to cover the top later.
2. Dissolve gelatine in hot water but make it one and half times as strong as the
instructions indicate on the packet (to make an extra stiff jelly) and make enough to one
third fill each container. .(All the gelatine may be made up at this stage and redissolved in
a microwave oven (about 20 seconds.) before stages B and C).
Place the boxes in the fridge until the gelatine is set (about one hour or overnight in the
lab. at room temperature). Also add gelatine to a plastic bag so that it will half fill one of
the boxes. Tie off and cut away any excess plastic above the knot (or tie). Allow to set.
This will represent the vacuole in the plant cell.
B
.1. Shape the nuclei, mitochondria, chloroplasts and ribosomes from different colours of
modelling clay or select other suitable materials to represent them. Keep their relative
sizes similar to those in the text book diagrams. Cover the nuclei in cling film and prick
holes in them with a mounted needle, to represent nuclear pores.
Add one nucleus, several mitochondria and ribosomes to each container. Add several
chloroplasts and the vacuole to the ‘plant cell’ only. Make sure the vacuole does not
protrude above the box.
Dissolve more gelatine as before. Allow to cool (not set) and pour into the boxes so that
they are now two thirds full. (Caution: If the jelly is too hot at this pouring stage it will
melt the set jelly in the container and all the parts will fall to the bottom). Allow to set.
C.
Add more mitochondria and ribosomes to both boxes and more chloroplasts to the plant
cell. Dissolve more gelatine as above. Allow to cool, and pour into the boxes to fill them.
Allow to set.
When set, place the cling film over the jelly in the ‘plant cell’. Trim off excess film and
place the lid on the container. The container and lid represent the cell wall and the cling
film represents the cell membrane.
Place the cling film over the jelly in the second container and trim as above and then
remove the jelly from the container. This is the animal cell.
Flag label the parts. Describe the structure and function of each part.