Topic 18: Organisms and their environment Flashcards
(17 cards)
What is the principal source of energy for biological systems?
The Sun.
How does energy flow through living organisms?
Energy flows from the Sun to plants (producers), then to herbivores (primary consumers), carnivores (secondary consumers), and further to higher-level consumers.
What is a food chain?
A food chain shows the transfer of energy from one organism to the next, beginning with a producer.
What is a food web?
A food web is a network of interconnected food chains.
What is a producer?
A producer is an organism that makes its own organic nutrients, usually using energy from sunlight through photosynthesis.
What is a consumer?
A consumer is an organism that gets its energy by feeding on other organisms.
What are the types of consumers?
Primary, secondary, tertiary, and quaternary consumers.
What is a herbivore?
A herbivore is an animal that gets its energy by eating plants.
What is a carnivore?
A carnivore is an animal that gets its energy by eating other animals.
What is a decomposer?
A decomposer is an organism that gets its energy from dead or waste organic material.
What is a trophic level?
A trophic level is the position of an organism in a food chain or food web.
Why do food chains usually have fewer than five trophic levels?
Because energy transfer between trophic levels is inefficient, with energy lost as heat, undigested material, and through respiration.
Why is it more energy-efficient for humans to eat plants than livestock?
Because it takes more energy to feed livestock plants to get a smaller amount of meat, making it less efficient than consuming plants directly.
What is the carbon cycle?
The carbon cycle describes the movement of carbon through photosynthesis, respiration, feeding, decomposition, fossil fuel formation, and combustion.
How do plants contribute to the carbon cycle?
Plants take in carbon dioxide from the atmosphere and convert it into organic material through photosynthesis.
How is carbon returned to the atmosphere?
Through respiration in plants and animals and through the decomposition of dead organisms.
What role do fossil fuels play in the carbon cycle?
Fossil fuels store carbon from dead organisms, which is released when burned during combustion.
