Ecosystems: Food Chains and Cycles

When animals break down glucose to create energy, they release water and carbon dioxide (CO2.) How can carbon dioxide (CO2) be reused within the food web?

• It can be used by animals as a source of oxygen.
• It can be used by both plants and animals to produce energy.
• It can be used by plants during photosynthesis to create glucose.

By which process is water taken from the ocean to form clouds?

• condensation
• evaporation
• transpiration

Which best describes what happens when an owl attacks and kills a fish for food?

• an interconnection between aquatic and terrestrial food webs.
• an interconnection between terrestrial organisms and predators
• an interconnection between aquatic food webs and decomposers

Which group in a food web is most likely to change atmospheric nitrogen into forms that are usable?

• consumers
• decomposers
• producers
• scavengers

Which shows the correct flow of energy through this simple food chain?

• fox → grass → rabbit
• grass → fox → rabbit
• grass → rabbit → fox
• rabbit → grass → fox

What is the energy source for the carbon dioxide cycle?

• plants
• the Sun
• respiration

Which best explains the role of bacteria in an ecosystem?

• They break down organic matter into necessary nutrient components.
•  They release energy from the decomposition of atmospheric gases.
• They convert carbon dioxide and water into simple carbohydrates.
• They absorb energy from the synthesis of inorganic compounds.

Which molecule is necessary in order for respiration to occur in plants and animals?

• nitrogen
• oxygen
• sulfur
• water

Which organisms recycle carbon in decaying matter back into atmospheric carbon dioxide? 

• fish
• fungi
• plants
• mammals

Which best describes the role plants serve in the oxygen cycle?

• They absorb oxygen during photosynthesis.
• They absorb oxygen during decomposition reactions.
• They release oxygen as a waste product of photosynthesis.
• They release oxygen as a waste product in cellular respiration.