Question

Which of the following chambers of the heart has the thickest muscular wall
a. Left atrium
b. Right atrium
c. Right ventricle
d. Left ventricle

Answer 1

Hint: The heart wall is composed of three layers, outer, the epicardium middle is the myocardium and the inner is the endocardium. The tissue layers are highly specialized and they perform different functions. The wave of depolarization during ventricular contraction, from the SA and AV nodes, moves from within the endocardial wall through the myocardial layer to the epicardial surface of the heart.

Complete answer:
- Cardiac muscle is known to have a high density of mitochondria and a large blood supply to keep it functioning continuously.
- There is a change in heart thickness over time and adapt to compensate for diseases, which often results in heart failure.
- Cardiac muscle is composed of sarcomeres, they are the basic, contractile units of muscle.
- Cardiac muscle is highly resistant to fatigue. They also have a large blood supply relative to their size and provide a continuous stream of nutrients and oxygen while removing metabolic waste.
- There are various levels of thickness within the heart. The thicker myocardium of the heart is able to pump blood with more pressure and force compared to chambers of the heart who have thinner myocardium.
- In the atria, the myocardium is the thinnest, as these chambers fill through passive blood flow.
- The myocardium in the right ventricle is thicker than the atrial myocardium, as this muscle pumps all blood returning to the heart into the lungs for oxygenation.
- In the left ventricle, the myocardium is thickest, as this chamber creates substantial pressure to pump blood into the aorta and throughout the systemic circulation.
- In the left ventricle, the myocardium is the thickest, as the left ventricle creates a lot of pressure to pump blood into the aorta and throughout the systemic circulation.
- The middle layer of the heart is the muscle tissue of the heart and the thickest layer of the heart wall is called the myocardium.
- It is composed of cardiac muscle cells, also known as cardiomyocytes. Cardiomyocytes are specialized muscle cells that contract like other muscle cells, but they differ in shape.
- The right ventricle has a thicker muscular wall.
- The right atrium does not have uniform thickness because of the terminal crest.
- The left atrium collects blood from pulmonary veins and pumps into the left ventricle.
- Hence the left ventricle has the thickest muscular wall.

So, the correct answer is option (D).

Note: The human heart consists of four chambers that are two superior atria and two inferior ventricles. The left ventricle of the heart is larger and thicker than the right ventricle. It pumps the blood around the body, against higher pressure, compared with the right ventricle. The heart consists of a tough muscular wall known as the myocardium. The left ventricle pumps oxygenated blood with greater force to all other visceral organs.