Which one of the following statements about starch and glycogen is correct ?
- A.Both starch and glycogen are found in plant cells.
- B.Both starch and glycogen are found in animal cells.
- C.Starch is present in plant cells and glycogen is present in animal cells.
- D.Both starch and glycogen are present in plant cells as well as animal cells.
Correct answer
Explanation
The correct answer is C, Starch is present in plant cells and glycogen is present in animal cells. Both are stored forms of glucose, but plants store it as starch and animals as glycogen.
Starch and glycogen are polysaccharides, long chains of glucose units. Plants make glucose by photosynthesis and store the extra as starch grains in leaves, seeds, roots and tubers such as potato. Animals and fungi store glucose as glycogen, mainly in the liver and muscles, which is why glycogen is often called animal starch. Glycogen is more branched than starch, so enzymes can release glucose from it quickly when the body needs energy.
A is wrong: glycogen is the animal store and is not the storage carbohydrate of plant cells.
B is wrong: animal cells do not store starch; they use glycogen.
D is wrong: each store belongs to one group; plants use starch and animals use glycogen.
Exam tip: starch – plants; glycogen (animal starch) – liver and muscles of animals; cellulose – plant cell wall; chitin – fungal cell wall and insect exoskeleton.
Practice Questions
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- A.S. Ramanujan
- B.S. Chandrasekhar
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- D.C. V. Raman
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The 2015 film 'The Man Who Knew Infinity' tells the life of the Indian mathematician Srinivasa Ramanujan and is based on Robert Kanigel's 1991 biography of the same name.
Read the full explanation →The word 'Denisovan' is sometimes mentioned in media in reference to
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- B.an early human species
- C.a cave system found in North-East India
- D.a geological period in the history of Indian subcontinent
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- A.They protect the body from environmental allergens.
- B.They alleviate the body's pain and inflammation.
- C.They act as immunosuppressants in the body.
- D.They protect the body from the diseases caused by pathogens.
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Read the full explanation →Which one of the following is not used as fertilizer?
- A.Ammonium nitrate
- B.Ammonium sulphide
- C.Ammonium phosphate
- D.Ammonium sulphate
Show answer
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Read the full explanation →The focal length of the objective lens of a telescope is 50 cm. If the magnification of the telescope is 25, then the focal length of the eye-piece is
- A.12.5 cm
- B.5 cm
- C.2 cm
- D.10 cm
Show answer
For an astronomical telescope in normal adjustment the magnifying power equals the focal length of the objective divided by that of the eyepiece, so the eyepiece focal length is 50 ÷ 25 = 2 cm.
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