Metals are essential for the proper Metals are essential for the proper functioning of living organisms. functioning of living organisms.

Some metal elements act as Some metal elements act as coenzymes and cofactors. These coenzymes and cofactors. These

elements are called elements are called trace metalstrace metals. . Without Without trace metalstrace metals certain certain

enzymes would not work.enzymes would not work.

Magnesium functions as part of the structure of chlorophyll. Chlorophyll is the green pigment that carries out photosynthesis.

MAGNESIUM IN CHLOROPHYLL

Iron forms part of the structureof haemoglobin which is thepigment in red blood cells thattransports oxygen around thebody. Iron is also essential forthe absorption of sunlight forenergy.

IRON IN HAEMOGLOBIN

Some metals are toxic to living organisms.The toxic metals are particularly ‘heavy’ metals. E.g. transition metals

POLLUTION BY METALS AND THEIR

COMPOUNDS

Mercury - from fossil fuel burning - dental fillings - canned tuna - manufacture of cement - fertilizers - compounds in the industry which causes

nervous disorders or even death.

Some toxic metals are:-

Lead - from lead headed nails - lead fuel from vehicle paints - car exhausts which affects

enzymes, impairing cell metabolism. It can cause brain damage and even death.

Some toxic metals are:-

Copper - from water pipes and heaters - copper jewellery/ copper pots - meat in which CuSO4 is used

as an enhancer.

Some toxic metals are:-

Many non-metals elements are continually being reused and recycled by nature and passed through the bodies of living organisms to be used by other organisms.

NON-METALS

Ensures a constant supply of water is available to

plants for photosynthesis. Ensures water is available to all living things to

keep their cells hydrated and to act as a solvent. Ensures aquatic organisms a place to live.

IMPORTANCE OF THE WATER CYCLE

THE WATER CYCLE

Maintains a constant level of CO2 in the air and

that a constant supply of carbon is available to plants for photosynthesis.

Ensures a constant supply of organic food is available to animals and decomposers.

IMPORTANCE OF THE CARBON CYCLE

THE CARBON CYCLE

Maintains a constant concentration of nitrogen in

the air. Ensures a continuous supply of nitrates protein

synthesis. Ensures a continuous supply of protein to animals

and decomposers.

IMPORTANCE OF THE NITROGEN CYCLE

THE NITROGEN CYCLE

1.Carbon dioxide is essential for

photosynthesis.

6CO2(g) + 6H2O(l) → C6H12O6(aq) + 6O2(g)

2.Oxygen is essential for aerobic respiration.

C6H12O6(aq) + 6O2(g) → 6CO2(g) + 6H2O(l) + energy

3.Nitrates and sulphates are essential for protein synthesis in plants.

IMPORTANCE OF NON-METALS

4.Phosphorus, obtained as PO4

3- ion is essential for building small bones and teeth.

5.Water is essential as: -a solvent to dissolve body chemicals and

enzymes so they can react. -for hydrolysis occurring during digestion. -as a reactant in photosynthesis. -as a coolant when it evaporates.

IMPORTANCE OF NON-METALS

Pollution is the contamination ofany feature of the environment byunpleasant or harmful substanceswithin the environment.

POLLUTION BY COMPOUNDS OF NON-METALS

Sulphur dioxide – combines with watervapour and smoke forming smog whichcauses respiratory diseases and evendeath. It also dissolves in rain water formingacid rain which is harmful to plants andanimals and corrodes metal structures andbuildings.

SOME HARMFUL POLLUTANTS

Hydrogen sulphide – extremely toxic andcauses respiratory disease.

Carbon monoxide – combines withhaemoglobin forming carboxyhaemoglobinwhich prevents blood carrying oxygen andresults in headaches, unconsciousness anddeath.

SOME HARMFUL POLLUTANTS

Carbon dioxide – the build up of heat causesatmospheric temperatures to rise resulting in ice caps and extensive flooding.

Insecticides – remain in environment andconcentrate up food chains harming andkilling top consumers.

SOME HARMFUL POLLUTANTS