Theory question 102
Food Substances and EnzymesThe table below shows the percentage composition of fat and protein in six different meat types. Study it and answer questions 2(a) to 2(d).
Meat type | Fat (%) | Protein (%)
A | 07.2 | 21.3
B | 25.3 | 10.6
C | 20.0 | 22.5
D | 03.1 | 28.2
E | 12.6 | 17.3
F | 13.2 | 14.3
(a)(i) Which two of the meat types may be recommended for an obese patient? (ii) State one reason for the answer in 2(a)(i). (b)(i) Which two of the meat types would provide the most energy? (ii) State two reasons for the answer in 2(b)(i). (c)(i) Which three of the meat types could be recommended for a child suffering from kwashiorkor? (ii) State one reason for the answer in 2(c)(i). (d) Which of the meat types would most likely be suitable for: (i) an active teenager; (ii) a 70 - year old human? (e) Which other class of food provides energy? (f) State three uses of fat in the human body. (g) Describe briefly the procedure for testing for fat in a meat sample using a piece of white paper.
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(a)(i) A and D.
(ii) They have the lowest fat content (and are rich in protein), so they add little extra energy to be stored as fat.
(b)(i) B and C.
(ii) They have the highest fat content; fat releases about twice as much energy per gram as carbohydrate or protein when oxidised.
(c)(i) D, C and A (the highest protein: 28.2, 22.5, 21.3%).
(ii) Kwashiorkor is caused by lack of protein, so the child needs meat rich in protein.
(d)(i) Active teenager: C (high in both fat for energy and protein for growth); B or E also accepted.
(ii) 70-year-old: D (high protein for repair, very low fat).
(e) Carbohydrates.
(f) Any three: source of energy; insulation (keeps body heat in); protects delicate organs; store of food; forms part of cell membranes; dissolves and carries vitamins A, D, E and K.
(g) Rub (or press) a piece of the meat on a clean white paper; leave the paper to dry (or warm it gently); hold it up to the light; a translucent (greasy) spot that does not dry away shows that fat is present.
Read the numbers from the table carefully before choosing.