The Respiratory System
ICSE · Class 9 · Biology
Flashcards for The Respiratory System — ICSE Class 9 Biology. Quick Q&A cards covering key concepts, definitions, and formulas.
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See them allWhat is respiration?
Answer
Respiration is the chemical process of releasing energy by breaking down glucose for carrying out life processes. It happens continuously in living cells and is different from simple breathing.
Write the overall respiration equation.
Answer
C6H12O6 + 6O2 → 6CO2 + 6H2O + energy. This shows that glucose is broken down using oxygen to release energy, carbon dioxide, and water.
Why is glucose important in respiration?
Answer
Glucose is the main substrate broken down in respiration to release energy. If it is not available directly, fats or proteins can be converted into glucose for respiratory needs.
What is ATP and why is it called the currency of energy?
Answer
ATP stands for adenosine triphosphate. It is the chemical form of energy produced during respiration and used by cells for activities. One mole of glucose yields 38 ATP in aerobic respiration and 2 AT…
What are the two main phases of cellular respiration inside the cell?
Answer
The two main phases are glycolysis and the Krebs cycle. Glycolysis occurs in the cytoplasm and breaks glucose into pyruvic acid with very little energy release. The Krebs cycle occurs inside mitochond…
What is glycolysis?
Answer
Glycolysis is the first phase of cellular respiration. It occurs in the cytoplasm outside mitochondria, is anaerobic, breaks glucose into pyruvic acid, and releases very little energy.
What is the Krebs cycle?
Answer
The Krebs cycle is the second phase of cellular respiration. It occurs inside mitochondria, needs oxygen, breaks down pyruvic or lactic acid step by step, produces ATP and carbon dioxide, and helps re…
Why do body cells need energy from respiration?
Answer
Body cells need energy for protein synthesis, enzyme production, muscle contraction, conduction of nerve impulses, cell division, and keeping the body warm in warm-blooded animals.
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