All flashcards
Flashcard 1: What is a food web?
Answer: A network of interconnected food chains in an ecosystem. Shows multiple feeding relationships in nature.
Flashcard 2: What is a heterotroph (consumer) in an energy-transfer system?
Answer: An organism that gets energy by eating other organisms. Must consume others because they can't produce their own food.
Flashcard 3: What is an autotroph (producer) in an energy-transfer system?
Answer: An organism that makes its own food from sunlight or chemicals. Self-feeders that don't depend on consuming others.
Flashcard 4: What molecule do producers make to store captured solar energy during photosynthesis?
Answer: Glucose (sugar) stores chemical energy. Plants convert CO₂ and water into this energy-rich molecule.
Flashcard 5: What is a trophic level?
Answer: A feeding position in a food chain or food web. Each level represents organisms with similar energy sources.
Flashcard 6: What is a decomposer, and what does it do to energy stored in dead organisms?
Answer: A decomposer breaks down dead matter and uses its chemical energy. Recycles nutrients by extracting remaining energy.
Flashcard 7: What is cellular respiration?
Answer: The process cells use to release energy from food molecules. Breaks glucose bonds to harvest ATP for cell work.
Flashcard 8: Which direction do arrows point in a food chain: toward the eater or toward the organism being eaten?
Answer: Toward the eater (the organism receiving energy). Shows energy flow direction, not who eats whom.
Flashcard 9: What energy-carrying molecule is produced for cell work during cellular respiration?
Answer: ATP. The universal energy currency of cells.
Flashcard 10: What gas is released as a product of photosynthesis?
Answer: Oxygen (O2). Byproduct from splitting water during light reactions.
Flashcard 11: What process captures energy from sunlight and stores it as chemical energy in glucose?
Answer: Photosynthesis. Converts light energy into chemical bonds in sugar molecules.
Flashcard 12: What term describes the path of energy transfer from one organism to another by eating?
Answer: Food chain. Linear sequence showing who eats whom in an ecosystem.
Flashcard 13: What term describes many interconnected food chains in an ecosystem?
Answer: Food web. Shows complex feeding relationships between organisms.
Flashcard 14: What are decomposers, and what is their role in energy transfer through ecosystems?
Answer: Organisms that break down dead matter and obtain energy. Recycle nutrients by breaking down organic matter.
Flashcard 15: Which trophic level eats producers directly: primary consumers or secondary consumers?
Answer: Primary consumers. Herbivores that feed directly on plants or algae.
Flashcard 16: Which level is always first in a food chain: producers or consumers?
Answer: Producers. They capture sunlight energy that feeds all other levels.
Flashcard 17: What molecule is the main immediate energy currency used by cells?
Answer: ATP. Adenosine triphosphate stores energy in phosphate bonds.
Flashcard 18: What process releases usable energy from glucose in cells, including plants and animals?
Answer: Cellular respiration. Breaks down glucose to release ATP for cellular work.
Flashcard 19: What substance is used in photosynthesis and split to help release oxygen?
Answer: Water (H2O). Provides electrons and hydrogen; splitting releases oxygen.
Flashcard 20: What gas is taken in by plants during photosynthesis to build sugars?
Answer: Carbon dioxide (CO2). Provides carbon atoms to build glucose during Calvin cycle.
Flashcard 21: Identify the correct energy flow direction: Sun → producer → consumer or consumer → producer → Sun?
Answer: Sun → producer → consumer. Energy flows one-way from sun through organisms.
Flashcard 22: Which is the best description of energy transfer when a rabbit eats grass: sunlight or chemical energy moves?
Answer: Chemical energy in food moves to the rabbit. Grass stores sunlight as chemical energy the rabbit uses.
Flashcard 23: What happens to most energy at each trophic level: it is recycled or released as heat?
Answer: Most energy is released as heat. Only ~10% transfers up; 90% lost to metabolism and heat.
Flashcard 24: What is the main energy-storing molecule produced by photosynthesis?
Answer: Glucose (sugar). Six-carbon sugar that stores energy from photosynthesis.
Flashcard 25: What is the original source of energy for most food chains and food webs on Earth?
Answer: The Sun. Provides light energy that drives photosynthesis in producers.
Flashcard 26: What are organisms called that obtain energy by eating other organisms?
Answer: Consumers (heterotrophs). Cannot make their own food, must consume other organisms.
Flashcard 27: What are organisms called that make their own food using sunlight energy?
Answer: Producers (autotrophs). Make their own food through photosynthesis or chemosynthesis.
Flashcard 28: What pigment absorbs light energy for photosynthesis in most plants?
Answer: Chlorophyll. Green pigment that captures light energy in photosystems.
Flashcard 29: What cell organelle is the main site of photosynthesis in plants and algae?
Answer: Chloroplast. Contains chlorophyll and enzymes needed for light reactions.
Flashcard 30: What process do plants and other producers use to convert sunlight into chemical energy?
Answer: Photosynthesis. Converts light energy into chemical bonds in glucose.