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The Aging Of The Lungs
As we age, our blood's ability to balance between oxygen and carbon dioxide is compromised. As a result, our bloodstream receives less oxygenated blood and our tissues are not able to regenerate as readily.
The lungs work by creating a vacuum to inhale air. As the oxygen-loaded air enters the lungs, past the bronchules to the alveoli, it diffuses into the capillaries and is picked up by red blood cells. In the same way, carbon dioxide diffuses from red blood cells into the lungs for its excretion.
If carbon dioxide is not exhaled completely, the air that occupies that space doesn't allow for oxygenated air to come in contact with the alveoli. This results in diminished oxygenation of the blood, a factor that is worsened by the process of aging.
A term called "elastic recoil" was given to humans' ability to resist the expansion of their lungs as they inhale. Elastic recoil is also involved in the opening of airways as carbon dioxide is excreted, so as to prevent oxygenated and deoxygenated air from mixing up.
As we age, the elastic recoil of our lungs is diminished, thus decreasing our ability to inhale air and eliminate carbon dioxide completely from the lungs. The used air remains inside, usually at the lower parts of the lungs, which makes us more prone to respiratory infections as we age.
Despite any physical activity, the decline of elastic recoil has a detrimental effect on our body's supply of oxygen. It's because of this that even the fittest individuals decline in stamina and exercise productivity as they age, even at younger stages of adulthood.
BONUS : The Anatomy of Joints and Bones
Joints and bones are what grant our body with structure, movement, and flexibility. If our bones and joints are compromised, so is our ability to move freely and painlessly.
Joints exist throughout the body in different forms. Some simply put pieces together, and others offer a moving pivot for the bones to flex.
Diarthonic joints connect bones and allow them to move. Examples of diarthonic joints include the elbows and knees.
Amphiartonic joints refer to those that offer the body partial mobility. They connect the bones and determine the direction and range of motion. An example is spinal discs, which allow the spine to move partially while blocking its ability to fully bend or twist.
Finally, synarthotic joints are those that simply connect pieces together. They occur mainly in large areas of bone that have no movement, such as the surface of the skull bone, for example.
Skeletal muscles are complex in nature as well. Their movement is granted by the myofibers that are contained within them, found organized and lined up, protected by an outer membrane called the sarcolemma. Within the nucleus of these cells, mitochondria fuel the myofibers by digesting nutrients and extracting their potential energy for the muscle to contract and relax.
As a muscle contracts, the strong protein molecules within the myofibers are forced to conglomerate with neighboring molecules, tensing up the tissue. As a result, we are able to move our bodies according to how joints have determined our movement to be.
Finally, nerves play a massive role in the transmitting of messages from the brain to the individual muscles, so as to stimulate a reaction via electrical impulses. Muscles are fed by endless webs of capillaries that enable the supply of blood in and out of muscle tissues. As the blood enters the muscles, it oxygenates and nourishes it. As it leaves, it takes away the waste products resulting from the digestion of oxygen and other nutrients.
Joints and bones are what grant our body with structure, movement, and flexibility. If our bones and joints are compromised, so is our ability to move freely and painlessly.
Joints exist throughout the body in different forms. Some simply put pieces together, and others offer a moving pivot for the bones to flex.
Diarthonic joints connect bones and allow them to move. Examples of diarthonic joints include the elbows and knees.
Amphiartonic joints refer to those that offer the body partial mobility. They connect the bones and determine the direction and range of motion. An example is spinal discs, which allow the spine to move partially while blocking its ability to fully bend or twist.
Finally, synarthotic joints are those that simply connect pieces together. They occur mainly in large areas of bone that have no movement, such as the surface of the skull bone, for example.
Skeletal muscles are complex in nature as well. Their movement is granted by the myofibers that are contained within them, found organized and lined up, protected by an outer membrane called the sarcolemma. Within the nucleus of these cells, mitochondria fuel the myofibers by digesting nutrients and extracting their potential energy for the muscle to contract and relax.
As a muscle contracts, the strong protein molecules within the myofibers are forced to conglomerate with neighboring molecules, tensing up the tissue. As a result, we are able to move our bodies according to how joints have determined our movement to be.
Finally, nerves play a massive role in the transmitting of messages from the brain to the individual muscles, so as to stimulate a reaction via electrical impulses. Muscles are fed by endless webs of capillaries that enable the supply of blood in and out of muscle tissues. As the blood enters the muscles, it oxygenates and nourishes it. As it leaves, it takes away the waste products resulting from the digestion of oxygen and other nutrients.
