The diaphragm is a large sheet of muscle that helps move air in and out of your lungs. Breathing is automatically controlled by the brain, but you can choose to hold your breath or breathe deeper. What kind of muscle do you suppose makes up the diaphragm? (Explain your answer.)

Verified step by step guidance

1. Identify the types of muscles in the human body: There are three main types of muscle tissue in the human body: skeletal, smooth, and cardiac.
2. Understand the characteristics of each muscle type: Skeletal muscles are usually attached to bones and are involved in voluntary movements. Smooth muscles are found in the walls of hollow organs and are involved in involuntary movements. Cardiac muscle is found only in the heart and is also involved in involuntary movements.
3. Consider the function of the diaphragm: The diaphragm is responsible for facilitating breathing by contracting and relaxing to change the volume of the thoracic cavity, which helps in drawing air into the lungs and expelling it out.
4. Analyze the control of the diaphragm's movement: Although breathing is an automatic process controlled by the brain, the diaphragm can also be controlled voluntarily, such as when you choose to hold your breath or breathe deeper.
5. Conclude the type of muscle: Based on the ability to control the diaphragm voluntarily and its role in movement attached to a bony structure (the rib cage), it is classified as a skeletal muscle.

Key Concepts

Muscle Types

There are three main types of muscle tissue in the human body: skeletal, cardiac, and smooth. Skeletal muscle is under voluntary control and is responsible for movement, cardiac muscle makes up the heart and is involuntary, while smooth muscle is found in organs and is also involuntary. The diaphragm is primarily composed of skeletal muscle, which allows for both involuntary and voluntary control during breathing.

Diaphragm Function

The diaphragm is a dome-shaped muscle located at the base of the thoracic cavity. It plays a crucial role in respiration by contracting and flattening during inhalation, which increases the volume of the thoracic cavity and draws air into the lungs. During exhalation, the diaphragm relaxes, allowing the lungs to expel air. This muscle's unique structure enables it to function effectively in both automatic and conscious breathing.

Neural Control of Breathing

Breathing is primarily regulated by the brainstem, which automatically controls the rhythm and depth of breathing based on the body's oxygen and carbon dioxide levels. However, the diaphragm's skeletal muscle composition allows for voluntary control, enabling individuals to hold their breath or take deeper breaths when desired. This dual control mechanism is essential for activities such as speaking, singing, or exercising.