A Respiratory System Is Needed If an Organism Is Too

question 11

Multiple Choice

A respiratory system is needed if an organism is too ____ to rely on the diffusion of gases through the body's tissues.

• A) small
• B) long
• C) thick
• D) thin
• E) round

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Definitions:

Antioxidants

Substances that can prevent or slow damage to cells caused by free radicals, unstable molecules that the body produces as a reaction to environmental and other pressures.

Vitamin E

A group of fat-soluble compounds that have antioxidant properties, protecting cells from the damage caused by free radicals.

Vitamin C

An essential nutrient that acts as an antioxidant, supports the immune system, and is necessary for the synthesis of collagen.

Kilocalories

A unit of energy defined as the amount of heat needed to raise the temperature of one kilogram of water by one degree Celsius, commonly used to quantify the energy content in food.