Zadanie 7, Paper 2, maj 2025, TZ2, Biologia IB SL

(a)

Coiling or branching makes the store compact. ✔

The large molecules are insoluble or poorly soluble; low osmotic effect is a valid consequence but is not required. ✔

Monomers can be added to store surplus fuel. ✔

Monomers can be removed by hydrolysis when fuel is needed. ✔

(b)

Photosynthesis converts light energy into chemical energy in organic molecules. ✔

Primary consumers obtain that energy by eating producers. ✔

Feeding transfers chemical energy along the chain. ✔

Energy is lost through respiration OR movement OR maintaining body temperature OR another named cellular process. ✔

Typically only a small fraction, often approximated as10%, transfers to the next trophic level. ✔

Energy availability decreases at successive trophic levels. ✔

This limits food-chain length. ✔

Decomposers obtain energy from dead organic material. ✔

(c)

Processes such as active transport, metabolism and movement require energy. ✔

ATP transfers usable energy to cellular processes. ✔

Energy input is needed to break substrate bonds during reactions. ✔

Synthesizing ATP requires energy OR ATP hydrolysis can supply energy for coupled processes. ✔

Respiration transfers chemical energy from organic fuels into ATP. ✔

Aerobic respiration in eukaryotes includes reactions in mitochondria. ✔

Aerobic respiration requires oxygen. ✔

Aerobic respiration yields more ATP per glucose than anaerobic pathways. ✔

Glucose OR fatty acids are common respiratory fuels. ✔

Aerobic oxidation produces carbon dioxide and water. ✔

Human cells produce lactate during anaerobic glycolysis. ✔

Quality: the whole answer is clear on first reading, focused and concise. ✔

Part(a): any3, maximum3; Part(b): any4, maximum4; Part(c): any8, maximum8. One holistic communication mark; total16. Accept a correct aerobic equation for oxygen requirement and carbon-dioxide/water products; accept glucose→lactate with ATP as the anaerobic alternative. Exact balancing is not required.