117k views
4 votes
Which of the following causes rigor in skeletal muscle?

1) No action potentials in motoneurons
2) An increase in intracellular Ca₂⁺ level
3) A decrease in intracellular Ca₂⁺ level
4) An increase in adenosine triphosphate (ATP) level
5) A decrease in ATP level

1 Answer

2 votes

Final answer:

Rigor in skeletal muscle is caused by a decrease in intracellular Ca²⁺ level and a decrease in ATP level. Additionally, a decrease in ATP level prevents the myosin heads from detaching from the actin-binding sites, further contributing to muscle rigidity.

Step-by-step explanation:

Rigor in skeletal muscle is caused by a decrease in intracellular Ca²⁺ level and a decrease in ATP level.

When the intracellular Ca²⁺ level decreases, the cross-bridges formed between myosin and actin cannot detach, resulting in muscle rigidity.

Additionally, a decrease in ATP level prevents the myosin heads from detaching from the actin-binding sites, further contributing to muscle rigidity.

User DavChana
by
8.3k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories