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Paper 4 · June 2004 · Enzymes

When catalase breaks down hydrogen peroxide in yeast, which gas is produced?

Model answer

oxygen

Also accepted: o2

Explanation

Catalase splits hydrogen peroxide (H2O2) into water and oxygen gas; the oxygen released is what relights a glowing splint.

Derived from ZIMSEC Biology Paper 4 (Practical Test), Jun 2004, Q3

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