The Partial Pressure of Oxygen in the Blood Returning to the Lungs

question 201

Multiple Choice

The partial pressure of oxygen in the blood returning to the lungs from the body is about

• A) 80 mm Hg
• B) 60 mm Hg
• C) 40 mm Hg
• D) 20 mm Hg

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Definitions:

Greenhouse Gas

Gases in Earth's atmosphere that trap heat, such as carbon dioxide, methane, and water vapor, contributing to the greenhouse effect.

Carbon Dioxide

A transparent, unscented gas formed by the burning of organic substances and carbon, also released during breathing, and absorbed by plants in the photosynthesis process.

Earth's Atmosphere

The layer of gases surrounding Earth, retained by the planet's gravity, composed primarily of nitrogen and oxygen, and protecting life by absorbing ultraviolet solar radiation and reducing temperature extremes.

Ancient Society

Human societies that existed in a time period that could be considered ancient or prehistoric, often characterized by early developments in social organization, culture, and technology.