Question

A surgeon removes two pieces of muscle from different parts of the body. Muscle A has alternating dark and light markings. Muscle B does not. Which of these statements is most likely true? (2 points) Muscle A is smooth muscle; muscle B is cardiac or skeletal muscle. Muscle A is skeletal or smooth muscle; muscle B is cardiac muscle. Muscle A is cardiac muscle; muscle B is skeletal or smooth muscle. Muscle A is cardiac or skeletal muscle; muscle B is smooth muscle.

Answer 1

Muscle A is cardiac or skeletal muscle; muscle B is smooth muscle

Answer 2

Answer:

Muscle A is cardiac or skeletal muscle; muscle B is smooth muscle

Explanation:

In order to answer the question, we need to review the anatomy of muscles. Basically, muscles can be divided into 2 types.

1. Striated Muscles
2. Smooth Muscles

Striated muscles are further divided into skeletal and cardiac muscles. Striated muscles possess contractile unit sacrcomeres which is responsible for its striated (striped) appearance under the microscope.

Smooth muscles do not possess striations and appear smooth under the microscope.

Coming back to the answer choices;

Muscle A is cardiac or skeletal muscle; muscle B is smooth muscle.

This is the correct option. It is stated in the question that Muscle A possesses light and dark markings (striations). Only striated muscle type possesses striations. Therefore, it correctly matches. It is further stated in the question that muscle B does not possess dark and light markings hence it implies that muscle B is smooth muscle and this answer choice correctly matches it.