Which one among the following combinations most appropriately represent the components of balanced diet?
- A.Carbohydrate, vitamins, proteins, fat, minerals, fibres and water
- B.Carbohydrate, vitamins, proteins, fat and minerals
- C.Carbohydrate, vitamins, proteins, minerals and water
- D.Vitamins, proteins, fat, minerals, fibres and water
Correct answer
Explanation
The correct answer is A, Carbohydrate, vitamins, proteins, fat, minerals, fibres and water. A balanced diet contains all the nutrients the body needs, along with roughage and water, in the right amounts.
Carbohydrates and fats give energy, proteins build and repair the body, and vitamins and minerals protect against disease and keep body processes running. Dietary fibre, also called roughage, gives no nutrients but helps the body pass out undigested food and prevents constipation. Water carries nutrients, helps remove wastes and keeps body temperature steady. A diet is balanced only when all seven of these are present in the proper proportion.
B is wrong because it leaves out fibres and water.
C is wrong because it leaves out fat and fibres; fats are a concentrated source of energy and help absorb vitamins A, D, E and K.
D is wrong because it leaves out carbohydrates, the main source of energy in the human diet.
Exam tip: the five main nutrients are carbohydrates, proteins, fats, vitamins and minerals; a balanced diet adds roughage and water to them.
Practice Questions
View allThe fact that the planets move around the Sun, not in circles but in ellipses, was first demonstrated by
- A.Galileo
- B.Martin Luther
- C.Johannes Kepler
- D.Copernicus
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In 1609 Kepler showed that the planets move around the Sun in elliptical orbits, with the Sun at one focus of the ellipse.
Read the full explanation →Which one of the following statements is correct?
- A.Urea is produced in liver.
- B.Urea is produced in blood.
- C.Urea is produced from digestion of starch.
- D.Urea is produced in lung and kidney.
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Liver cells turn the toxic ammonia released from the breakdown of amino acids into urea through the ornithine cycle, also called the urea cycle.
Read the full explanation →Which one of the following is the correct sequence of passage of light in a compound microscope?
- A.Condenser-Objective lens-Eyepiece-Body tube
- B.Objective lens-Condenser-Body tube-Eyepiece
- C.Condenser-Objective lens-Body tube-Eyepiece
- D.Eyepiece-Objective lens-Body tube-Mirror
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Light passes through the condenser to the specimen, is picked up by the objective lens, travels up the body tube and reaches the eye through the eyepiece.
Read the full explanation →Which one of the following statements regarding haemoglobin is correct?
- A.Haemoglobin present in RBC can carry only oxygen but not carbon dioxide.
- B.Haemoglobin of RBC can carry both oxygen and carbon dioxide.
- C.Haemoglobin of RBC can carry only carbon dioxide.
- D.Haemoglobin is only used for blood clotting and not for carrying gases.
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It binds oxygen at its iron-containing haem groups and carries some carbon dioxide on its protein chains. Each haemoglobin molecule has four polypeptide chains and four haem groups, and each haem iron can hold one oxygen molecule, forming oxyhaemoglobin in the lungs.
Read the full explanation →Which one of the following statements regarding histone proteins is correct?
- A.Histones are proteins that are present in mitochondrial membrane.
- B.Histones are proteins that are present in nucleus in association with DNA.
- C.Histones are proteins associated with lipids in the cytosol.
- D.Histones are proteins associated with carbohydrates in the cytosol.
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They are the proteins around which DNA winds to form chromatin in the nucleus of eukaryotic cells. Histones are small basic proteins, rich in the positively charged amino acids lysine and arginine, which attract the negatively charged phosphate groups of DNA.
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