Question
Describe the structure of an actin filament.
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Answer
- Each actin filament is made of two 'F' (filamentous) actins that are helically wound to each other.
- Each 'F' actin is a polymer of many 'G' (globular) actins.
- Two filaments of protein, tropomyosin also run close to the F-actins through out their length.
- Another complex protein, troponin, is distributed at regular intervals on the tropomyosin; a subunit of troponin masks the active/binding site for myosin on the actin filaments.
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Column I
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Column II
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a.
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Cristae
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i.
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b.
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ii.
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c.
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