Question

When comparing the contractile responses in smooth and skeletal muscle, which of the following is most different?

a. The source of activator calcium
b. The role of calcium in initiating contraction
c. The mechanism of force generation
d. The source of energy used during contraction
e. The nature of the contractile proteins

Answer 1

Option d is the correct answer. The most different aspect when comparing contractile responses in smooth and skeletal muscle is the source of energy used during contraction.

Step-by-step explanation:

The most different aspect when comparing the contractile responses in smooth and skeletal muscle is d. The source of energy used during contraction.

In skeletal muscle, ATP provides the energy for contraction. However, in smooth muscle, enzymes are activated by calcium ions, which in turn activate myosin heads, allowing contraction to occur.

Therefore, while both types of muscles use calcium to initiate contraction and have similar mechanisms of force generation and contractile proteins, the source of energy used during contraction is different between smooth and skeletal muscle.