Which of the following pair of plastids – thing stored is NOT correct? I. Amyloplasts – oils and fats II. Aleuroplasts – carbohydrates
- A.Only I
- B.Both I and II
- C.Neither I nor II
- D.Only II
Correct answer
Explanation
The correct answer is B, Both I and II. Both pairs are wrong. Amyloplasts store starch, a carbohydrate, and aleuroplasts store proteins; oils and fats are stored by elaioplasts. Plastids are organelles found only in plant cells. Chloroplasts hold chlorophyll and do photosynthesis, chromoplasts hold the yellow, orange and red pigments of flowers and fruits, and leucoplasts are colourless storage plastids. The leucoplasts are named after what they keep: amyloplasts keep starch (amylum), as in potato tubers; elaioplasts keep oils (elaion means oil), as in castor seeds; aleuroplasts keep proteins (aleurone), as in the outer layer of wheat grains. A is wrong because it accepts pair II, which links aleuroplasts to carbohydrates instead of proteins. C is wrong because it treats both pairs as correct. D is wrong because it accepts pair I, which links amyloplasts to fats instead of starch. Exam tip: amylo = starch, elaio = oil, aleuro = protein; all three are leucoplasts.
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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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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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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