MP Board Class 10 Science 2027 — Solving the Model Paper With a Teacher's Notes

A note before we start: I've been correcting MPBSE Science answer sheets for a decade, and the same handful of mistakes show up every single year — not because students don't know the syllabus, but because they don't know how the syllabus gets graded. So instead of just giving you a model paper, I've marked up each section the way I would if you handed this to me for correction.

Sit down with a timer, 3 hours, no notes, and attempt the full paper first. Then come back and read through the notes below each answer.

---

Before You Start: How the 100 Marks Break Down

Theory is 75 marks, internal assessment is 25. The internal 25 is the easiest quarter of your total score — practicals, project work, viva — and most students who lose marks there lose them to absenteeism, not lack of knowledge. Show up to your practical classes. That's the whole trick.

Section	Type	Marks
Section A	MCQ	5
Section B	Very Short Answer (2 marks)	10
Section C	Short Answer (3 marks)	15
Section D	Long Answer (4 marks)	16
Section E	Diagram/Experiment-based	29

---

Section A — MCQ

1. The chemical formula for baking soda is: (a) Na₂CO₃ (b) NaHCO₃ (c) NaOH (d) Na₂SO₄ Answer: (b) NaHCO₃

2. In the human eye, the image is formed on the: (a) Cornea (b) Iris (c) Retina (d) Pupil Answer: (c) Retina

3. Which of these is a decomposition reaction? (a) 2H₂ + O₂ → 2H₂O (b) CaCO₃ → CaO + CO₂ (c) Fe + S → FeS (d) NaOH + HCl → NaCl + H₂O Answer: (b)

4. The unit of current is: (a) Volt (b) Ohm (c) Ampere (d) Watt Answer: (c) Ampere

5. Which hormone regulates blood glucose? (a) Adrenaline (b) Thyroxine (c) Insulin (d) Estrogen Answer: (c) Insulin, secreted by the beta cells of the Islets of Langerhans in the pancreas.

Marking note: five marks, five seconds of doubt each is fine — five minutes of doubt each is not. If you don't know it in fifteen seconds, mark your best guess and move. There's no penalty for wrong answers here.

---

Section B — Very Short Answer (2 Marks)

6. What is a balanced chemical equation?

A chemical equation with equal numbers of atoms of each element on both sides. Example: 2H₂ + O₂ → 2H₂O (4 H atoms and 2 O atoms on each side).

7. Define refraction. State Snell's Law.

Refraction is the bending of light as it passes between media of different optical density. Snell's Law: sin i / sin r = n₂/n₁ = μ.

8. What are heredity and variation?

Heredity is the transmission of traits from parent to offspring through genes. Variation is the difference in traits among individuals of the same species, or between parent and offspring.

9. Name two functions of the kidneys.

Excretion (filtering urea, uric acid, creatinine from blood) and osmoregulation (balancing water and salt levels).

10. A 60W bulb runs on 220V. Find the current.

I = P/V = 60/220 = 0.27 A

Marking note: on question 10, I still see students write "0.27" with no unit and lose half a mark for it every year. The number isn't the answer — the number with its unit is the answer.

---

Section C — Short Answer (3 Marks)

11. Explain photosynthesis. Write the equation and name four factors affecting it.

Photosynthesis is how green plants make glucose from CO₂ and water using sunlight and chlorophyll: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Four factors: light intensity, CO₂ concentration, temperature (optimum 25–35°C), water availability.

12. State Ohm's Law and derive the formula for resistors in series.

Ohm's Law: V = IR, at constant temperature.

For resistors R₁, R₂, R₃ in series, the same current I flows through all three: V = V₁+V₂+V₃ = I(R₁+R₂+R₃) → Req = R₁+R₂+R₃

13. Define acids and bases with three differences.

Property	Acid	Base
Taste	Sour	Bitter
pH	Below 7	Above 7
Litmus	Blue→red	Red→blue

Marking note: question 12 is where the "correct final formula, zero working" answer costs students the most. MPBSE gives step-marks for the derivation itself — write "same current flows through each resistor" as your opening line even though it feels obvious. It isn't optional; it's a scored step.

---

Section D — Long Answer (4 Marks)

14. Describe the structure and working of the human heart, with a diagram.

Four chambers (RA, RV, LA, LV), valves (tricuspid, bicuspid, semi-lunar), and double circulation:

Pulmonary: deoxygenated blood → right atrium → right ventricle → lungs (via pulmonary artery) Systemic: oxygenated blood → left atrium → left ventricle → body (via aorta)

SA node initiates the heartbeat (~72 beats/min).

(Draw the four chambers with valves labelled — this diagram alone carries dedicated marks separate from your written explanation.)

15. Differentiate sexual and asexual reproduction. Explain two methods of vegetative propagation.

Sexual reproduction needs two parents and gametes, producing genetic variation. Asexual reproduction needs one parent, no gametes, and produces genetically identical offspring.

Stem cuttings: a node-bearing stem piece grows roots when planted (rose, sugarcane). Budding: a bud grafted onto a related rootstock grows using its nutrients (mango, apple).

Marking note: I dock more marks here for missing diagrams than for wrong biology. Students genuinely know this content — they just don't draw. Budget two full minutes per Section D diagram, every time.

---

Section E — Practice for the Diagram/Experiment Section

These follow the same style as Section E but are for your own practice.

A labelled neuron diagram, with nerve impulse explained: dendrite → cell body → axon → axon terminal, with the impulse released as neurotransmitter across the synapse. Label all five parts — MPBSE checks each one individually.

Aerobic vs anaerobic respiration: aerobic fully breaks down glucose with oxygen, releasing more energy (C₆H₁₂O₆+6O₂→6CO₂+6H₂O+Energy); anaerobic partially breaks it down without oxygen, into lactic acid (muscles) or ethanol+CO₂ (yeast), releasing less energy.

The nitrogen cycle: nitrogen fixation (Rhizobium bacteria, lightning) → nitrification (ammonia to nitrites to nitrates) → assimilation (plants absorb nitrates) → ammonification/denitrification (returns nitrogen to air).

A numerical: 2A through a 5Ω resistor for 10 minutes. H = I²Rt = 4×5×600 = 12,000 J.

---

Chapter-Wise Weightage

Chapter	Marks
Chemical Reactions	10
Acids, Bases and Salts	8
Light	10
Electricity	10
Life Processes	10
Reproduction and Heredity	8
Natural Resources	7
Carbon Compounds	7
Metals and Non-Metals	5

Chemical Substances and the World of Living together make up more than half the theory paper. If your revision time is genuinely limited, that's where to spend it.

---

I tell every batch the same thing before their board exam: MPBSE Science is not a paper that punishes weak students, it's a paper that punishes rushed diagrams and missing units. Fix those two habits and most of you will outscore what your mock tests predicted.