Mark the following statements as true for smooth muscle tissue, cardiac muscle tissue, and/or skeletal muscle tissue.

a. ____Actin attaches to dense bodies.
b. ____Cells are joined by intercalated discs.
c. ____The thick and thin filaments are arranged into sarcomeres.
d. ____The thick filaments contain myosin heads along their entire length.
e. ____The cells depolarize and contract as a unit.
f. ____ Ca2+ binding to troponin is the initiating event of contraction.
g. ____Ca2+ binding to calmodulin is the initiating event of contraction.
h. ____The sarcolemma has a distinct motor end plate.

Question

Mark the following statements as true for smooth muscle tissue, cardiac muscle tissue, and/or skeletal muscle tissue.

a. ____Actin attaches to dense bodies.

b. ____Cells are joined by intercalated discs.

c. ____The thick and thin filaments are arranged into sarcomeres.

d. ____The thick filaments contain myosin heads along their entire length.

e. ____The cells depolarize and contract as a unit.

f. ____ Ca2+ binding to troponin is the initiating event of contraction.

g. ____Ca2+ binding to calmodulin is the initiating event of contraction.

h. ____The sarcolemma has a distinct motor end plate.

Accepted Answer

Hey, everyone. Let's take a look at this question together which of the following statements describes cardiac muscle contraction. Is it answer choice. A? It can be controlled voluntarily. Answer choice B it is typically fast and forceful answer. Choice C it is under the control of the somatic nervous system. Answer choice D it is initiated by the sinoatrial node or answer choice. E all options are correct. Let's work this problem out together to try to figure out which of the following answer choices best describes cardiac muscle contraction. So in order to solve this question, we have to recall what we have learned about cardiac muscle contraction, which we know that cardiac muscle contraction is an initiated by the heart's pacemaker, which we know that the heart's pacemaker refers to the sinoatrial or S A node in which the S A node generates electrical impulses which spread through the heart and coordinate the rhythmic contractions that are necessary for pumping blood. So looking at our answer choices, we can identify answer choice D which says it is initiated by the Sino H or S A node, which is the correct answer. Since cardiac muscle contraction is initiated by the sinoatrial or S A node. And we know all other answer choices are incorrect since answer choice A which says it can be controlled voluntarily is incorrect. Since cardiac muscle contraction is not controlled voluntarily, and instead is involuntarily controlled. And we know answer choice is incorrect since they are typically not fast and forceful and answer choice C is incorrect. Answer choice C says it is under the control of the somatic nervous system, which we know it is not under control of the somatic nervous system and instead is under the control of the autonomic nervous system. So answer choice D is the only correct answer choice. I hope you found this video to be helpful. Thank you and goodbye.

Verified Solution

Key Concepts

Muscle Tissue Types

Contraction Mechanisms

Cellular Structures