Carbon Cycle Quiz

What is a key nutrient for life that cycles through Earth's spheres?

• Oxygen

• Nitrogen

• Carbon

• Hydrogen

What does it mean when we say all life on Earth is "carbon-based"?

• Life forms are made primarily of water.

• Life forms have carbon as a component of most of their molecules.

• Life forms are made primarily of oxygen.

• Life forms do not contain any carbon.

Why is carbon considered essential to life on Earth?

• It is the most abundant element in the universe.

• It forms the backbone of nucleic acids, proteins, carbohydrates, and fatty acids.

• It is the primary source of energy for life forms.

• It is the only element found in the atmosphere.

What is a unique property of carbon that makes it a backbone for many molecules?

• It can form two bonds with a variety of elements.

• It can form four bonds with a variety of elements.

• It can form only single bonds.

• It cannot form bonds with other elements.

What is the second most abundant element in the human body after oxygen?

• Hydrogen

• Nitrogen

• Carbon

• Calcium

What is the role of carbon dioxide (CO₂) in photosynthesis?

• It is released as a waste product.

• It is converted into glucose.

• It is used to produce ATP.

• It is broken down into oxygen.

During cellular respiration, what happens to glucose?

• It is converted into carbon dioxide and water.

• It is stored as ATP.

• It is used to produce oxygen.

• It is broken down into nitrogen.

Which process involves the conversion of sunlight, water, and carbon dioxide into oxygen and sugar in plants?

• Cellular respiration

• Fermentation

• Photosynthesis

• Glycolysis

What is the main purpose of cellular respiration in cells?

• To produce glucose and oxygen

• To convert sunlight into energy

• To produce energy by using oxygen and glucose

• To store carbon dioxide

What are carbon sources?

• Processes that absorb more carbon than they release

• Processes that release more carbon into the atmosphere than they absorb

• Natural reserves of carbon

• Areas where carbon is stored permanently