Key scientific ideas – cells 2
Cells use the nutrients from
food to help an organism
work properly.
Some food substances are
made up of very large
molecules. Enzymes break
these down quickly for the
organism to use.
The circulatory system
transports useful substances
like nutrients and oxygen to
all cells in the body.
The digestive system uses
enzymes produced by the
cells to break-down food
substances into smaller,
more useful molecules.
Cells transfer energy through
respiration, which often
needs oxygen. This helps to
keep the organism alive.
Enzyme
Carbohydrate + Oxygen
Carbon dioxide + Water
Energy
Enzyme
C6H12O6 + 6O2
6CO2 + 6H2O
It also transports waste
products away from the cells.
Energy
Digestive system
Teeth
Tongue
Salivary glands
Oesophagus
Liver
Stomach
Gall bladder
Duodenum
Pancreas
Colon (large intestine)
Ileum (small intestine)
Appendix
Rectum
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Based upon an idea and approach developed by The Cams Hill Science Consortium.
Many diseases are caused by
micro-organisms.
Viruses
Bacteria
Fungi
Antibiotics are drugs that can
cure some diseases caused by
bacteria.
Bacteria and fungi are singlecelled organisms.
Vaccination can protect against
some illnesses caused by
viruses and bacteria.
The body’s own defence
system protects us against
infection by many microorganisms.
0.0001mm
0.005mm
0.00001mm
How enzymes work
Starch molecule
Glucose molecules
Enzyme
Useful vocabulary
Cells of the
gut wall
Cell
Organ
Cell membrane
Glucose in blood
Micro-organism
Bacteria
Circulatory system
Upper Limbs and head
Immunisation
Vaccine
Antibodies
Lungs
Digestion
Cell wall
Pulmonary
artery
Enzyme
Heart
Virus
Liver
Fungi
Pulmonary
vein
Aorta
Digestive
system
Kidneys
Antibiotics
Disinfectant
Rest of body
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