The ratio of actin : troponin : tropomyosin molecules in an thin filament is:: (A) 1:01:01, (B) 1:03:05, (C) 1:07:07, (D) 7:01:01
Answer is D. A thin filament has 3 molecules - actin troponin tropomyosin in a ratio of 7: 1: 1.