20 Questions Flashcards
(20 cards)
What is the principal source of energy input to biological systems?
The Sun.
How does energy initially enter living organisms from the Sun?
Through light energy captured by producers during photosynthesis.
Where does energy in living organisms eventually go?
It is transferred to the environment, often as heat.
What does a food chain show?
The transfer of energy from one organism to the next, starting with a producer.
What is an organism that makes its own organic nutrients called?
A producer.
What process do producers usually use to make their own food?
Photosynthesis.
What is an organism that gets its energy by feeding on other organisms called?
A consumer.
Name the three main classes of consumers based on their position in a food chain.
Primary consumers, secondary consumers, and tertiary consumers.
What is an animal that gets its energy by eating plants called?
A herbivore.
What is an animal that gets its energy by eating other animals called?
A carnivore.
What is an organism that gets its energy from dead or waste organic material called?
A decomposer.
What is a network of interconnected food chains called?
A food web.
What is the position of an organism in a food chain or food web called?
A trophic level.
List the trophic levels in a food chain or food web, starting with the base.
Producers, primary consumers, secondary consumers, tertiary consumers, (and sometimes quaternary consumers).
Why is the transfer of energy from one trophic level to another often not efficient?
Organisms use energy for life processes (like movement and respiration), and some energy is lost as heat or in waste products.
Why do food chains usually have fewer than five trophic levels?
Due to energy loss at each level, there isn’t enough energy to support a large number of organisms at higher trophic levels.
Why is it more energy efficient for humans to eat crop plants than to eat livestock that have been fed on crop plants?
Energy is lost when crop plants are eaten by livestock, and then more energy is lost when humans eat the livestock. Eating the plants directly means humans get the energy closer to its source.
Name two processes in the carbon cycle that release carbon dioxide into the atmosphere.
Respiration and combustion.
Name two processes in the carbon cycle that remove carbon dioxide from the atmosphere.
Photosynthesis and the formation of fossil fuels (over very long periods).
How do feeding and decomposition contribute to the carbon cycle?
Feeding transfers carbon between organisms, and decomposition releases carbon from dead organic matter back into the environment (soil and atmosphere).
