Everything Life Sciences Grade 10

Micro-elements(micro-nutrients) are nutrients that are required in very small quantities for
development and growth and include iron, cobalt, chromium, copper, iodine, manganese,
selenium, zinc and molybdenum.

Table 2.2 below summarises some important minerals required for proper functioning of the
human body. Proper nutrition involves a diet in which the daily requirements of the listed
mineral nutrients are met.

Mineral Food Source Main Functions Deficiency

Disease

Macro-nutrients

Calcium (Ca) most fruit and

vegetables, meat,

dairy products

strong bones and teeth;

muscle contraction; blood

clotting; nerve function

rickets,

osteoporosis

Magnesium (Mg) nuts, meat, dairy

products

strong bones and teeth;

nerve and muscle function;

energy production

osteoporosis,

muscle cramps

Phosphorus (P) nuts, meat, dairy

products

strong bones and teeth;

nerve function; part of

nucleic acids and cell

membranes

rickets,

osteoporosis

Potassium (K) bananas, meat, dairy

products

growth and maintenance,

water balance, heart function

muscle cramps;

heart, kidney and

lung failure

Sodium (Na) table salt, fruit and

vegetables

regulates blood pressure and

volume; muscle and nerve

function

muscle cramps

Sulfur (S) meat, dairy products,

eggs, legumes

part of proteins; detoxifies

the body; good skin; hair

and nails

disorder unlikely

Micro-nutrients

Iron (Fe) meat, legumes part of haemoglobin (the

oxygen transport protein);

part of some enzymes

anaemia

Iodine (I) seafood, iodated salt production of hormones by

the thyroid gland; strong

bones and teeth; good hair;

skin and nails

goitre, stunted

growth, mental

problems

Zinc (Zn) seafood, meat immune function; male

reproductive system

stunted growth,

prostate problems

Table 2.2: Minerals required by humans.

Nutrients required for plant growth

The previous section examined the key nutrients important for animal growth. In Table??
we will now look at the key nutrients required for plant growth.

Chapter 2. The chemistry of life 27