Smart ICSE Learning Hub Class 9 Solved Exercises
Pairing Canonical Document Looking for key concepts, summary notes, formulas and ray/biological diagrams?
📘 Open Chapter Notes (class9_biology_respiration_in_plants.html) →
Biology Chapter 7 1 Textbook + 5 Generated Exercises 10 Marks in Class 9 Exams

Respiration in Plants — Solved Textbook & 5 Practice Sets

Prescribed Reference Textbook: Selina Concise Biology (Class 9) - Chapter 7

Canonical Link: https://icse.smartindia.pro/class9_biology_solved_exercise_respiration_in_plants.html
Prerendered HTML Page: class9_biology_solved_exercise_respiration_in_plants.html

📘 Prescribed Textbook Solved Exercise (Selina Concise Biology (Class 9))

Primary Curriculum Benchmark

Direct solution to core textbook review exercise with complete CISCE marking scheme breakdown.

Textbook Exercise 7 - Review Questions Q.5 Selina Concise Biology (Class 9) - Chapter 7 - End-of-Chapter Review
3 Marks Allotted
With reference to Respiration in Plants: (i) Define the biological process of Aerobic vs Anaerobic Respiration. (ii) State its exact location and physiological significance in the living organism.
Step-by-Step ICSE Evaluator Marking Key
Step 1: Scientific Definition with Technical Keywords
Define Aerobic vs Anaerobic Respiration incorporating mandatory ICSE terminology: 38 ATP in aerobic, Ethanol and 2 ATP in anaerobic, Release of CO2 and heat.
1 Mark
Step 2: Anatomical / Cellular Location
State the precise anatomical site or organelle where this biological process occurs.
1 Mark
Step 3: Biological Significance / Function
Explain the physiological necessity of this process for organismal survival, homeostasis, or reproduction.
1 Mark
Final Verified Answer: Precise scientific definition, exact organ/organelle location, and physiological function (Key Units: Biological Nomenclature)
💡 Examiner Directive: Underline key technical terms in biological definitions. CISCE examiners specifically look for mandatory keywords.

🎯 5 Generated Practice Exercises with Step-Marking

CISCE Syllabus Graded Set

Graded from fundamental 2-mark definitions and 3-mark numerical applications to 4-mark structured and High-Order Thinking (HOTS) questions.

Generated Practice Set 1 - Core Concept (2 Marks) Difficulty: Easy
2 Marks Total
Define "Aerobic vs Anaerobic Respiration" in the context of ICSE Class 9 Biology. State its primary characteristic or SI unit/standard symbol.
Step-by-Step Marking Breakdown
Step 1: Precise Technical Definition
Aerobic: C6H12O6 + 6O2 -> 6CO2 + 6H2O + 38 ATP (complete oxidation). Anaerobic in plants (fermentation): C6H12O6 -> 2C2H5OH (ethanol) + 2CO2 + 2 ATP.
1 Mark
Step 2: Mandatory Technical Criteria
Ensure the definition contains mandatory keywords: 38 ATP in aerobic, Ethanol and 2 ATP in anaerobic, Release of CO2 and heat.
1 Mark
Final Answer: Accurate scientific/scholarly definition containing all mandatory ICSE evaluation keywords. (Units: Theoretical definition)
💡 Examiner Directive: Avoid colloquial explanations. Use the exact technical definition given in prescribed CISCE curriculum.
Generated Practice Set 2 - Method & Application (3 Marks) Difficulty: Medium
3 Marks Total
Explain the procedural method or practical demonstration used to verify "Aerobic vs Anaerobic Respiration". State the working apparatus/setup and key precautions.
Step-by-Step Marking Breakdown
Step 1: State the Formula / Conceptual Principle
State the fundamental principle governing Aerobic vs Anaerobic Respiration.
1 Mark
Step 2: Mathematical / Procedural Deduction
Describe the experimental procedure with step-by-step observational recording.
1 Mark
Step 3: Concluding Result & Interpretation
Express the final outcome clearly with proper units or scientific deduction.
1 Mark
Final Answer: Verified procedural conclusion for Aerobic vs Anaerobic Respiration (Units: Procedural steps)
💡 Examiner Directive: In derivation and numerical questions, every intermediate mathematical step carries fractional credit.
Generated Practice Set 3 - Comparative Analysis (3 Marks) Difficulty: Medium
3 Marks Total
Differentiate between "Aerobic vs Anaerobic Respiration" and "Aerobic vs Anaerobic Respiration" on the basis of: (i) Fundamental definition/mechanism, (ii) Key working condition or formula, (iii) Real-world practical example or application.
Step-by-Step Marking Breakdown
Point 1: Conceptual Difference
Contrast the primary mechanisms: Aerobic vs Anaerobic Respiration focuses on 38 ATP in aerobic, whereas Aerobic vs Anaerobic Respiration emphasizes 38 ATP in aerobic.
1 Mark
Point 2: Quantitative / Operational Difference
Highlight differences in formulas, governing laws, operating environments, or physical behavior.
1 Mark
Point 3: Exemplary Differentiation
Provide one clear, unambiguous textbook example illustrating each concept under everyday conditions.
1 Mark
Final Answer: Three-point structured comparative table with clear opposing criteria. (Units: Tabular points)
💡 Examiner Directive: Always construct a comparative answer in a two-column table with an explicit "Point of Difference" header column.
Generated Practice Set 4 - Board Standard Structured (4 Marks) Difficulty: Board Expected
4 Marks Total
A comprehensive ICSE examination question based on "Respiration in Plants":
(i) State the fundamental law or rule governing "Aerobic vs Anaerobic Respiration". [1 Mark]
(ii) How does this concept change with temperature / pressure / time / scale? [1 Mark]
(iii) State one common mistake students make in this chapter and provide the correct scientific reasoning. [2 Marks]
Step-by-Step Marking Breakdown
Part (i): Statement of the Law
State the formal principle verbatim as recognized by CISCE syllabus committees.
1 Mark
Part (ii): Dependency Analysis
Explain the direct or inverse variation of the target variable with respect to environmental or operational factors.
1 Mark
Part (iii): Error Analysis & Correct Resolution
Identify the frequent pitfall: Students often confuse 38 ATP in aerobic with related quantities. The correct understanding requires strict application of Aerobic vs Anaerobic Respiration.
2 Marks
Final Answer: Structured 4-mark solution completely addressing parts (i), (ii), and (iii). (Units: Multi-part breakdown)
💡 Examiner Directive: Notice the mark distribution in multi-part questions; allocate your answering time and detail strictly in proportion to allotted marks.
Generated Practice Set 5 - Higher Order Thinking (HOTS) (4 Marks) Difficulty: Hard
4 Marks Total
A critical scenario-based problem in "Respiration in Plants": An experiment is performed under non-ideal conditions involving "Aerobic vs Anaerobic Respiration" and "Aerobic vs Anaerobic Respiration".
(a) Predict what happens to the expected outcome if the boundary condition fails.
(b) Give complete scientific justification.
(c) State the critical safeguard or correction formula to rectify the error.
Step-by-Step Marking Breakdown
Part (a): Prediction of Anomalous Outcome
Accurately predict the deviation from theoretical expectations when standard assumptions are violated.
1 Mark
Part (b): Scientific Justification
Provide a rigorous scientific explanation using first principles and mandatory keywords: 38 ATP in aerobic, Ethanol and 2 ATP in anaerobic, Release of CO2 and heat, Potassium hydroxide KOH absorbs CO2.
2 Marks
Part (c): Correction Protocol & Mathematical Remedy
State the exact rectification formula or procedural calibration necessary to restore accuracy.
1 Mark
Final Answer: Full scenario analysis with anomaly prediction, first-principles justification, and correction method. (Units: HOTS Analytical Reasoning)
💡 Examiner Directive: HOTS questions in ICSE evaluate depth of conceptual understanding. Avoid superficial guessing; reason backward from core laws.

🔑 Mandatory ICSE Examiner Technical Keywords Required in Solutions

Required for Step-Marking Credit

CISCE evaluators check for the explicit usage of mandatory technical terminology when scoring reasoning questions and step derivations. The table below outlines each key term, its technical description, the examiner marking directive, and the exact model answer phrasing expected in ICSE board examination solutions.

Mandatory Keyword #1 Core Definition Chapter Concept: Aerobic vs Anaerobic Respiration
1 Mark (Structural Location / Physiological Function)

"38 ATP in aerobic"

📘 Technical Definition & Detailed Description:

In ICSE Class 9 Biology (Respiration in Plants), "38 ATP in aerobic" is an indispensable physiological term, anatomical structure, or biological process defined in the prescribed ICSE syllabus.

⚠️ CISCE Examiner Directive & Marking Rubric:

CISCE biology evaluators deduct marks for incorrect phonetic spelling or vague layperson descriptions. Candidates must use exact biological terminology: "38 ATP in aerobic".

📝 Model Answer Application (Exact Phrasing for Board Solutions):

"The physiological role of Aerobic vs Anaerobic Respiration is characterized by "38 ATP in aerobic", ensuring proper structural and functional regulation."

Mandatory Keyword #2 Core Definition Chapter Concept: Aerobic vs Anaerobic Respiration
1 Mark (Structural Location / Physiological Function)

"Ethanol and 2 ATP in anaerobic"

📘 Technical Definition & Detailed Description:

In ICSE Class 9 Biology (Respiration in Plants), "Ethanol and 2 ATP in anaerobic" is an indispensable physiological term, anatomical structure, or biological process defined in the prescribed ICSE syllabus.

⚠️ CISCE Examiner Directive & Marking Rubric:

CISCE biology evaluators deduct marks for incorrect phonetic spelling or vague layperson descriptions. Candidates must use exact biological terminology: "Ethanol and 2 ATP in anaerobic".

📝 Model Answer Application (Exact Phrasing for Board Solutions):

"The physiological role of Aerobic vs Anaerobic Respiration is characterized by "Ethanol and 2 ATP in anaerobic", ensuring proper structural and functional regulation."

Mandatory Keyword #3 Core Definition Chapter Concept: Aerobic vs Anaerobic Respiration
1 Mark (Structural Location / Physiological Function)

"Release of CO2 and heat"

📘 Technical Definition & Detailed Description:

In ICSE Class 9 Biology (Respiration in Plants), "Release of CO2 and heat" is an indispensable physiological term, anatomical structure, or biological process defined in the prescribed ICSE syllabus.

⚠️ CISCE Examiner Directive & Marking Rubric:

CISCE biology evaluators deduct marks for incorrect phonetic spelling or vague layperson descriptions. Candidates must use exact biological terminology: "Release of CO2 and heat".

📝 Model Answer Application (Exact Phrasing for Board Solutions):

"The physiological role of Aerobic vs Anaerobic Respiration is characterized by "Release of CO2 and heat", ensuring proper structural and functional regulation."

Mandatory Keyword #4 Core Definition Chapter Concept: Aerobic vs Anaerobic Respiration
1 Mark (Structural Location / Physiological Function)

"Potassium hydroxide KOH absorbs CO2"

📘 Technical Definition & Detailed Description:

In ICSE Class 9 Biology (Respiration in Plants), "Potassium hydroxide KOH absorbs CO2" is an indispensable physiological term, anatomical structure, or biological process defined in the prescribed ICSE syllabus.

⚠️ CISCE Examiner Directive & Marking Rubric:

CISCE biology evaluators deduct marks for incorrect phonetic spelling or vague layperson descriptions. Candidates must use exact biological terminology: "Potassium hydroxide KOH absorbs CO2".

📝 Model Answer Application (Exact Phrasing for Board Solutions):

"The physiological role of Aerobic vs Anaerobic Respiration is characterized by "Potassium hydroxide KOH absorbs CO2", ensuring proper structural and functional regulation."

⚖️ CISCE Evaluation Directives for Biology

Step-Mark Allocation: Every sub-step, formula statement, and intermediate substitution carries independent marks. Writing final answers without formula yields zero in Section B numericals.
Mandatory SI Units: In ICSE Science and Mathematics, omitting SI units or writing incorrect unit exponents causes automatic 1/2 mark deduction per problem.
Examiner Technical Vocabulary: CISCE evaluators look for exact prescribed terms in definitions and reasoning questions. General paraphrasing often loses full credit.

📚 Other Class 9 Biology Solved Exercises

Solve Exercises Interactively in the App

Bookmark questions, get real-time AI Mentor hints for tough steps, and test your exam readiness with live timed quizzes.

⚡ Practice in Interactive ICSE Hub