The Major Source of Oxygen in Earth's Atmosphere Is from ______

question 26

Multiple Choice

The major source of oxygen in Earth's atmosphere is from ______.

• A) photosynthesis
• B) swamp gas emissions
• C) the decay of plants
• D) respiration of animals

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Definitions:

Blood Pumped

Describes the process of the heart moving blood throughout the body's circulatory system.

Cardiorespiratory Fitness

The ability of the heart, lungs, and vascular system to supply oxygen-rich blood to working muscles during sustained physical activity.

Oxygen-rich Air

Air that has a higher concentration of oxygen than is found at sea level, often used for therapeutic purposes or in high-altitude environments.

Lungs

Respiratory organs responsible for exchanging oxygen and carbon dioxide between the blood and the air.