Explanation

• ECG (Electrocardiogram) is a test used to measure the electrical activity of the heart.

It is commonly used for the diagnosis of heart-related ailments, such as:

• Arrhythmias (irregular heart rhythms)
• Coronary artery disease
• Cardiac arrests
• Heart failure

Explanation

The heart is the organ responsible for pumping blood throughout the human body.

It ensuring that oxygen and nutrients are delivered to tissues and organs.

Explanation

The percentage of oxygen in the air is about 20.95%.

The air is made up of many gases, including oxygen, nitrogen, argon, and carbon dioxide

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Nitrogen

Nitrogen is the most abundant gas in the air, making up about 78% of it. 

Argon

Argon is the third most abundant gas in the air, making up about 0.93% of it. 

Carbon dioxide

Carbon dioxide is present in trace amounts in the air, making up about 0.04% of it. 

Explanation

In humans and higher animals, the exchange of gases (oxygen and carbon dioxide) is carried out by the respiratory processes, which include:

• Breathing (inhalation and exhalation)
• Transport of gases through the blood
• Exchange of gases in the lungs (oxygen in, carbon dioxide out)

Explanation

Respiration involves two main processes:

1. Mechanical Process (Ventilation):

• Breathing in (inhalation)
• Breathing out (exhalation)
• Movement of air in and out of the lungs

2. Biochemical Process (Respiratory Exchange):

• Exchange of oxygen and carbon dioxide between the lungs and blood
• Transport of oxygen and carbon dioxide through the bloodstream
• Cellular respiration (cellular metabolism)