OXYGEN

We breathe because oxygen is required for the combustion of fuel [sugars and fatty acids] in our cells to produce energy.

The most abundant element in the human body is oxygen. It is mostly found in water, bound to hydrogen. Water, in turn, makes up approximately 60% of the human body and is involved in numerous metabolic reactions. The element oxygen serves as an electron acceptor as well as an oxidizing agent.

What Oxygen (O2) does with our body?

Actual Working:

Oxygen fuels our cells and contributes to the basic building blocks required by our bodies to survive. Our cells combine oxygen, nitrogen, and hydrogen to produce a variety of proteins that aid in the formation of new cells.
When oxygen is combined with carbon and hydrogen, carbohydrates are formed, which provide energy to our bodies and allow us to do what we do. Oxygen is also required for the formation of replacement cells in our bodies.
The lungs are where oxygen enters our cells and tissues. The lungs take in oxygen from the air and then release it into the bloodstream via millions of tiny air sacs known as alveoli. Hemoglobin in red blood cells then absorbs the oxygen and transports it to the body's tissues and cells.
It is also strongly recommended that we breathe through our noses because they have structures that clean and filter the air before it reaches our lungs.
Every day, approximately 700 billion cells in our bodies wear out and must be replaced. Our bodies cannot create new cells without oxygen.

Why do we need oxygen?

Respiration:

Every living thing requires oxygen. In fact, every tissue and cell in the body requires a steady supply of oxygen to function properly.
Through a system known as the electron transport chain (ETC), which is an important component of cellular respiration, oxygen plays an important role in energy production in the cell. Cellular respiration is the process by which all cells generate energy.
A chemical equation can be used to represent the process of cellular respiration. The materials that begin the chemical equation are referred to as reactants, and the materials that are produced are referred to as products. ATP is produced by all cellular respiration processes that use glucose as a reactant.
Aerobic cellular respiration has the chemical equation as follows:

Glucose + Oxygen = Water + Carbon Dioxide + ATP

O2 Transport:

Despite the fact that oxygen dissolves in blood, only a small amount of oxygen is transported in this manner. Only about 1.5 percent of the oxygen in the blood is dissolved directly in the blood. The majority of oxygen, 98.5 percent, is bound to a protein called hemoglobin and transported to the tissues.

Important factor of a biological factor:

The final electron acceptor in cellular respiration is oxygen. After passing through the electron transport chain and ATPase, the enzyme responsible for creating high-energy ATP molecules, electrons are accepted by oxygen.
Oxygen serves as the final electron acceptor in the electron transfer chain, resulting in the formation of H2O. This is necessary because without it, the electron transfer chain cannot function, resulting in a lack of oxidative phosphorylation in the mitochondrial inner membrane.

Abnormalities due to lack of (O2):

Oxygen has Main 2 deficiencies like ;

Hypoxemia:

When the levels of oxygen in the blood are lower than normal, this is referred to as hypoxemia. Your body may not function properly if your blood oxygen levels are too low.
Mild symptoms of hypoxia include headaches and shortness of breath. It can impair heart and brain function in severe cases.

Hypoxia:

The brain relies on blood to supply it with oxygen on a continuous basis. Thus, disruptions to any part of the body involved in blood or oxygen supply can result in hypoxia.
The four primary causes of hypoxia are :-
No blood supply to the brain
Low blood supply to the brain
No blood oxygen
Low blood oxygen

Normal Value:

A normal level of oxygen is usually 95% or higher.
Some people with chronic lung disease or sleep apnea can have normal levels as high as 90%.

How to Measure Oxygen:

Oximetry:

This is the most common method. A small clip-on device shines a light through your finger or earlobe and measures the amount of light absorbed by red blood cells' oxygen-carrying hemoglobin.
The device can determine how saturated the hemoglobin is with oxygen molecules, or O2 sat, by calculating the amount of light absorption. The oxygen saturation of the blood is normally between 98 and 100 percent.

Arterial blood gas analysis:

Using a needle and syringe, blood is drawn from an artery, usually in the wrist, during this procedure. The blood is then passed through an analyzer to determine the amount of oxygen gas dissolved in it.
This is known as arterial oxygen pressure (paO2), and it is normally between 80 and 100 mm Hg.

Facts:

Oxygen gas has no color, odour, or taste. It is typically purified through fractional distillation of liquefied air, but the element can be found in a variety of compounds, including water, silica, and carbon dioxide.
Oxygen promotes combustion. It is, however, not truly flammable! It is classified as an oxidizer. Pure oxygen bubbles do not burn.
The color of liquid and solid oxygen is pale blue. At lower temperatures and higher pressures, oxygen's appearance changes from blue monoclinic crystals to orange, red, black, and even metallic.
The aurora's bright red, green, and yellow-green colors are caused by excited oxygen. It is the most important molecule in producing bright and colorful auroras.

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