Question

question
which of the following statements regarding cardiac muscle tissue is false?
answer
cardiocytes average 10 - 20 μm in diameter and 50 - 100
μm in length.
all of the listed statements are true; none is false.
myofibrils in muscle cells anchor firmly to the
sarcolemma at the intercalated disc.
cardiac muscle cells are connected by gap junctions,
which create an indirect electrical connection.

Explanation:

• Cardiocytes (cardiac muscle cells) have an average diameter of 10 - 20 μm and length of 50 - 100 μm. This is a correct structural description.
• Myofibrils in cardiac muscle cells anchor to the sarcolemma at intercalated discs. This is a correct anatomical feature.
• Cardiac muscle cells are connected by gap junctions which create a direct electrical connection (not indirect). This makes the statement about gap junctions false.

Answer:

Cardiac muscle cells are connected by gap junctions, which create an indirect electrical connection.