Theory question 101
Food Substances and Enzymes(a) What is a balanced diet?
(b) (i) Name four classes of food other than proteins.
(ii) Give one example of food substance for each class named.
(c) (i) State three functions of proteins in humans.
(ii) Describe the appearance of a child with protein deficiency.
(d) (i) Name one organelle in a living cell that produces enzymes. (ii) Mention two enzymes that act on proteins.
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(a) A balanced diet is a meal that contains all the classes of food (carbohydrates, proteins, fats and oils, vitamins, mineral salts and water, with roughage) in the right amounts for the person's needs.
(b)(i) and (ii) Any four with an example each: carbohydrates – rice, yam, bread, garri; fats and oils – groundnut oil, palm oil, butter; vitamins – fresh fruits such as oranges, vegetables, carrots; mineral salts – vegetables, milk, table salt; water – drinking water, fruit juice.
(c)(i) Any three: growth/building new cells; repair of worn-out tissues; making enzymes; making hormones; making antibodies; source of energy when carbohydrates and fats are short.
(ii) Kwashiorkor signs: stunted growth; swollen (pot) belly; swelling (oedema) of feet and legs; thin arms and legs; cracked, peeling skin with pale patches; thin hair that turns reddish-brown; tired, unhappy look.
(d)(i) Ribosome.
(ii) Any two: pepsin; trypsin; rennin; erepsin (peptidases).
Pair each food class with a correct named example.