Biology Flashcards: Model Matter And Energy Cycling

What this deck covers

This deck focuses on Model Matter And Energy Cycling, giving you a quick way to review the definitions, rules, and examples that matter most for Biology.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: What form of energy is captured by photosynthesis to build glucose?

Answer: Light (radiant) energy from the Sun. Solar energy provides the power to drive photosynthetic reactions.

Flashcard 2: Which gas is consumed during photosynthesis and often reduces atmospheric $CO_2$?

Answer: $CO_2$. Plants absorb this gas from air to build glucose molecules.

Flashcard 3: What is the overall balanced chemical equation for aerobic cellular respiration (using glucose)?

Answer: $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{ATP}$. Breaks down glucose with oxygen to produce carbon dioxide, water, and ATP.

Flashcard 4: Which process is occurring if a cell consumes $O_2$ and releases $CO_2$ while making ATP?

Answer: Aerobic cellular respiration. These are the characteristic inputs and outputs of cellular respiration.

Flashcard 5: Identify the process: $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{ATP}$.

Answer: Aerobic cellular respiration. This equation shows glucose being oxidized to release energy as ATP.

Flashcard 6: Identify the process: $6CO_2 + 6H_2O + \text{light} \rightarrow C_6H_{12}O_6 + 6O_2$.

Answer: Photosynthesis. This equation shows light energy converting $CO_2$ and water into glucose.

Flashcard 7: Find the missing coefficient: C_6H_{12}O_6 + _O_2 \rightarrow 6CO_2 + 6H_2O.

Answer: $6$. Balance requires 6 oxygen molecules to produce 6 $CO_2$ molecules.

Flashcard 8: Find the missing coefficient: $_CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$.

Answer: $6$. Balance requires 6 carbon atoms on each side of the equation.

Flashcard 9: Identify the correct matching: chloroplast function or mitochondrion function?

Answer: Chloroplast: makes sugars; mitochondrion: makes ATP from sugars. Each organelle has a distinct role in energy conversion processes.

Flashcard 10: Which process builds glucose from smaller molecules: photosynthesis or respiration?

Answer: Photosynthesis. This process uses energy to assemble glucose from carbon dioxide.

Flashcard 11: Which process breaks down glucose to release energy: photosynthesis or respiration?

Answer: Cellular respiration. This process breaks chemical bonds to release stored energy.

Flashcard 12: Identify whether aerobic cellular respiration is endergonic or exergonic overall.

Answer: Exergonic (releases energy). This process releases energy by breaking down glucose molecules.

Flashcard 13: Identify whether photosynthesis is endergonic or exergonic overall.

Answer: Endergonic (requires energy input). This process requires energy input to build glucose from smaller molecules.

Flashcard 14: What is the main carbon-containing product exported from the Calvin cycle (simplified for HS biology)?

Answer: Sugar (ultimately glucose, $C_6H_{12}O_6$). The Calvin cycle produces this organic molecule from $CO_2$ fixation.

Flashcard 15: What is the immediate energy product of light-dependent reactions used to power sugar synthesis?

Answer: ATP and NADPH. These energy carriers power the Calvin cycle reactions.

Flashcard 16: Choose the correct direction of carbon dioxide cycling between the two processes.

Answer: Respiration produces $CO_2$; photosynthesis consumes $CO_2$. These processes cycle carbon dioxide in opposite directions.

Flashcard 17: Choose the correct direction of oxygen cycling between the two processes.

Answer: Photosynthesis produces $O_2$; respiration consumes $O_2$. These processes cycle oxygen in opposite directions between organisms and atmosphere.

Flashcard 18: Which statement best describes energy flow in ecosystems involving these processes?

Answer: Energy enters as light and leaves as heat; it does not cycle. Energy flows one-way through ecosystems and is ultimately lost as heat.

Flashcard 19: Which statement best describes matter cycling between photosynthesis and respiration?

Answer: Atoms in $CO_2$, $H_2O$, glucose, and $O_2$ are rearranged and reused. Matter is conserved and recycled between these complementary processes.

Flashcard 20: Which process returns carbon from glucose to atmospheric $CO_2$?

Answer: Cellular respiration. This process releases carbon from organic molecules back to the atmosphere.

Flashcard 21: Which process directly cycles carbon from atmospheric $CO_2$ into organic molecules?

Answer: Photosynthesis (carbon fixation in the Calvin cycle). This process incorporates atmospheric carbon into organic compounds.

Flashcard 22: What is the source of the $O_2$ released during photosynthesis: $CO_2$ or $H_2O$?

Answer: $H_2O$. Water molecules are split to provide electrons, releasing oxygen gas.

Flashcard 23: Identify the waste product formed when $O_2$ accepts electrons and $H^+$ in aerobic respiration.

Answer: $H_2O$. Oxygen combines with electrons and protons to form this molecule.

Flashcard 24: Identify the molecule that is the final electron acceptor in aerobic respiration.

Answer: $O_2$. This molecule receives electrons at the end of the transport chain.

Flashcard 25: Where is the electron transport chain located in mitochondria?

Answer: Inner mitochondrial membrane. This membrane contains the protein complexes that transport electrons.

Flashcard 26: What is the name of the respiration stage that uses a proton gradient to make most ATP?

Answer: Oxidative phosphorylation (electron transport chain + chemiosmosis). This process uses electron flow to pump protons and synthesize ATP.

Flashcard 27: Where does the Krebs cycle occur in eukaryotic cells?

Answer: Mitochondrial matrix. This inner compartment houses the enzymes for the citric acid cycle.

Flashcard 28: What is the name of the cycle in mitochondria that releases $CO_2$ from acetyl-CoA?

Answer: Krebs cycle (citric acid cycle). This cyclical pathway completely oxidizes acetyl groups to $CO_2$.

Flashcard 29: Where in a eukaryotic cell does glycolysis occur?

Answer: Cytoplasm (cytosol). This cellular compartment is where glucose is initially broken down.

Flashcard 30: What is the name of the first major stage of cellular respiration that splits glucose?

Answer: Glycolysis. This pathway breaks glucose into two pyruvate molecules.