Question

How would muscle contractions be affected if ATP was completely depleted in a muscle fiber?

a)Myosin heads will detach rapidly from the actin-binding sites, resulting in muscle relaxation. In a live person this causes rigor mortis, while in a recently dead person it results in “writer’s cramp”.

b)Myosin heads will not detach from the actin-binding sites, resulting in muscle stiffness. In a live person this causes rigor mortis, while in a recently dead person it results in “writer’s cramp”.

c)Myosin heads will detach rapidly from the actin-binding sites, resulting in muscle relaxation. In a live person this causes “writer’s cramp”, while in a recently dead person it results in rigor mortis.

d)Myosin heads will not detach from the actin-binding sites, resulting in muscle stiffness. In a live person this causes “writer’s cramp”, while in a recently dead person it results in rigor mortis.

Answer 1

a)Myosin heads will detach rapidly from the actin-binding sites, resulting in muscle relaxation. In a live person this causes rigor mortis, while in a recently dead person it results in “writer’s cramp”. THIS IS INCORRECT AS MYOSIN CANNOT DETACH WITHOUT ATP.

b)Myosin heads will not detach from the actin-binding sites, resulting in muscle stiffness. In a live person, this causes rigor mortis, while in a recently dead person it results in “writer’s cramp”. This is incorrect as in dead person a person suffers from rigor mortis.

c)Myosin heads will detach rapidly from the actin-binding sites, resulting in muscle relaxation. In a live person, this causes “writer’s cramp”, while in a recently dead person it results in rigor mortis. THIS IS INCORRECT AS MYOSIN CANNOT DETACH WITHOUT ATP.

d)Myosin heads will not detach from the actin-binding sites, resulting in muscle stiffness. In a live person, this causes “writer’s cramp”, while in a recently dead person it results in rigor mortis.

This is correct as myosin will not detach and in dead person it will cause rigor mortis.