15 Most Important Diagrams for Class 10 Science 2025

To visualise the biological processes or to understand the concepts in physics, diagrams are an important part of the Class 10 Science Syllabus. A secret weapon that can help in illustrating chemistry experiments makes the entire learning process easy and engaging. Board exams 2025 are around the corner, so mastering the important diagrams for Class 10 Science isn’t just a study tip–it’s a must-follow scoring strategy.

Why juggle between multiple study materials when on this page, you can find all the all-important diagrams of class 10 science PDF for quick revision before the exam? Also, find the frequently asked diagrams in the CBSE Science exams and understand why to practice the diagrams.

Let’s get started making the diagrams, a scoring asset in the 2025 board exams.

List of Most Important Diagrams for Class 10 Science 2025

Below you can find the detailed all-important diagrams of the class 10 science PDFs.

Important Diagrams for Class 10 Science Biology

Cross-section of a Leaf

You will notice that some cells contain green dots. These green dots are cell organelles called chloroplasts which contain chlorophyll.

(i) Absorption of light energy by chlorophyll.

(ii) Conversion of light energy to chemical energy and splitting of water molecules into hydrogen and oxygen.

(iii) Reduction of carbon dioxide to carbohydrates.

Open and Closed Stomatal Pores

Nutrition in Amoeba

Nutrition in Human Beings

Mouth:

Saliva is secreted by salivary glands and contains an enzyme called salivary amylase.
Salivary amylase breaks down starch (a complex molecule) into simple sugars.
Food is mixed with saliva and moved around the mouth by the muscular tongue for thorough chewing.

Oesophagus (Food Pipe):

The oesophagus moves food from the mouth to the stomach.
Peristaltic movements (rhythmic muscle contractions) push food forward along the digestive tube.

Stomach:

The stomach expands when food enters.
Muscular walls help mix the food with digestive juices.
Gastric glands in the stomach wall secrete:

Hydrochloric acid to create an acidic medium.

Pepsin, a protein-digesting enzyme.

Mucus for protection of the stomach lining.

Pepsin works in an acidic environment to digest proteins.

Sphincter Muscles (Stomach):

Regulate the exit of food from the stomach in small amounts to the small intestine.

Small Intestine:

Longest part of the alimentary canal is coiled to fit into a compact space.
Villi, finger-like projections on the inner lining, increase surface area for absorption.
Blood vessels in villi transport absorbed nutrients to body cells for energy, tissue building, and repair.

Large Intestine:

Unabsorbed food enters the large intestine.
The wall of the large intestine absorbs more water from the unabsorbed material.

Anus and Anal Sphincter:

Regulates the exit of waste material from the body.
The anal sphincter controls the release of waste via the anus.

Human Respiratory System

Nostrils:

Air is taken into the body through the nostrils.
Fine hairs in the nostrils filter the incoming air.
Mucus in the passage also aids in filtering the air.

Throat:

Air passes from the nostrils through the throat on its way to the lungs.
Rings of cartilage in the throat prevent the air passage from collapsing.

Lungs:

The passage divides into smaller tubes as it enters the lungs.
The smaller tubes eventually terminate in alveoli, which are balloon-like structures for gas exchange.

Alveoli:

Alveoli provide a surface for gas exchange (oxygen and carbon dioxide).
The walls of the alveoli contain an extensive network of blood vessels for gas exchange.

Breathing Process:

Ribs lift and the diaphragm flattens during inhalation, enlarging the chest cavity.
The expanded chest cavity creates a suction that draws air into the lungs and fills the alveoli.

Gas Exchange:

Oxygen from the alveoli is absorbed into the blood and transported to body cells.
Carbon dioxide is carried by the blood from the body to the alveoli for release during exhalation.

Residual Volume:

During the breathing cycle, the lungs always contain a residual volume of air.
This ensures sufficient time for oxygen absorption and carbon dioxide release during breathing.

Germination of Pollen on the Stigma

Longitutional Section of Flower

Structure of a nephron

Receptors:

Specialized tips of nerve cells detect information from the environment.
Receptors are typically located in sense organs (e.g., inner ear, nose, tongue).
Gustatory receptors detect taste, and olfactory receptors detect smell.

Nerve Cell and Dendritic Tips:

The information detected by the receptors sets off a chemical reaction at the dendritic tip of the nerve cell.
The chemical reaction generates an electrical impulse.

Transmission of Impulse:

The electrical impulse travels from the dendrite to the cell body of the neuron.
The impulse then travels along the axon to its end.

Axon Terminals and Chemical Release:

At the end of the axon, the electrical impulse triggers the release of chemicals.

Synapse and Impulse Transfer:

The chemicals cross the synapse (the gap between neurons) to start a similar electrical impulse in the dendrite of the next neuron.

Impulses to Other Cells:

The synapse allows the delivery of electrical impulses from neurons to other cells, such as muscle cells or glands, enabling responses in the body.

Human Brain

Brain Regions:

The brain consists of three major parts: fore-brain, midbrain, and hind-brain.

Fore-brain:

The main thinking part of the brain.
Receives sensory impulses from various receptors.
Separate areas are specialized for senses such as hearing, smell, and sight.
Association areas interpret sensory information by combining it with existing knowledge.
Based on interpretation, decisions are made on how to respond, and the information is passed to motor areas controlling voluntary muscle movement (e.g., leg muscles).
Includes a hunger centre that helps us sense when we are full.

Midbrain:

Controls involuntary actions such as certain reflexes, like changes in pupil size.
Plays a role in muscle movement that doesn't require conscious control.

Hind-brain:

Medulla (in the hind-brain) controls involuntary actions such as blood pressure, salivation, and vomiting.
The cerebellum (in the hind-brain) ensures the precision of voluntary actions.
Helps in maintaining posture and balance.
Responsible for coordinating activities like walking in a straight line, riding a bicycle, and picking up a pencil.

Human Eye

Human Eye as a Camera:

The eye functions similarly to a camera.
The lens system of the eye forms an image on the retina (light-sensitive screen).

Cornea:

Light enters the eye through the cornea, a thin membrane.
The cornea is a transparent bulge on the front surface of the eyeball.
Most of the refraction (bending of light) occurs at the outer surface of the cornea.

Eyeball and Refraction:

The eyeball is approximately spherical, with a diameter of about 2.3 cm.
The crystalline lens helps in the finer adjustment of the focal length to focus objects at different distances on the retina.

Iris:

The iris is a dark muscular diaphragm behind the cornea.
The iris controls the size of the pupil, which regulates the amount of light entering the eye.

Pupil:

The pupil controls the amount of light entering the eye by adjusting its size.

Retina:

The eye lens forms an inverted real image of the object on the retina.
The retina is a delicate membrane with a large number of light-sensitive cells.
These cells are activated by light and generate electrical signals.

Optic Nerve and Brain:

The electrical signals from the retina are sent to the brain via the optic nerves.
The brain processes and interprets these signals, allowing us to perceive objects as they are.

Food Chains and Webs

Trophic Levels:

Each step or level of the food chain forms a trophic level.
Autotrophs or producers are at the first trophic level, capturing solar energy and making it available to consumers (heterotrophs).
Herbivores (primary consumers) are at the second trophic level.
Small carnivores (secondary consumers) are at the third trophic level.
Larger carnivores (tertiary consumers) form the fourth trophic level.
The energy moves from autotrophs to heterotrophs and decomposers.

Energy Capture by Green Plants:

Green plants in a terrestrial ecosystem capture about 1% of the sunlight energy and convert it into food energy.

Energy Loss in the Food Chain:

When green plants are eaten by primary consumers, much of the energy is lost as heat to the environment, used in digestion, or used in work.
A small amount of energy goes towards growth and reproduction.
On average, 10% of the food consumed is converted into the body of the consumer, which becomes available to the next level.

Energy Transfer Efficiency:

10% of the energy is transferred to the next level at each trophic level.
This explains why food chains typically have 3-4 levels—the energy loss at each step is too great for more levels to be sustainable.

Energy and Population at Different Trophic Levels:

There are generally more individuals at the lower trophic levels, with producers having the greatest number.
As energy moves up through the food chain, it diminishes progressively.

Food Webs:

Food chains are often not linear; instead, they form food webs where each organism is eaten by multiple other organisms.
A food web shows a series of branching relationships between organisms.

Unidirectional Flow of Energy:

The flow of energy is unidirectional, meaning it moves from autotrophs to consumers and does not revert back to the original source (solar energy).
Energy that passes to higher trophic levels is no longer available to the previous levels.

Diminishing Energy at Higher Trophic Levels:

The energy available at each trophic level diminishes progressively due to energy loss at each level.

Important Diagrams for Class 10 Science Physics

Myopia

Myopia (Nearsightedness):

Myopia is the condition of nearsightedness where a person can see nearby objects clearly but cannot see distant objects distinctly.
The far point of a person with myopia is closer than infinity, typically only a few meters away.

Cause of Myopia:

Myopia can occur due to:

Excessive curvature of the eye lens.
Elongation of the eyeball.

Image Formation in Myopia:

In a myopic eye, the image of a distant object is formed in front of the retina instead of directly on it.

Correction of Myopia:

Myopia can be corrected by using a concave lens of suitable power.
The concave lens helps bring the image back onto the retina, correcting the defect.

Hypermetropia

Hypermetropia (Far-sightedness):

Hypermetropia is the condition of far-sightedness, where a person can see distant objects clearly but cannot see nearby objects distinctly.
The near point of a person with hypermetropia is farther than the normal near point of 25 cm.

Difficulty in Near Vision:

A person with hypermetropia needs to hold reading material at a distance beyond 25 cm to see it clearly.
This is because the light rays from a nearby object are focused at a point behind the retina.

Cause of Hypermetropia:

The defect can occur due to:

The focal length of the eye lens is too long.
The eyeball being too small.

Correction of Hypermetropia:

Hypermetropia can be corrected by using a convex lens of appropriate power.
Convex lenses provide the necessary focusing power to form the image correctly on the retina, improving near vision.

Refraction of Light through a Prism

Different colours of light bend through different angles concerning the incident ray, as they pass through a prism. The red light bends the least while the violet the most. Thus the rays of each colour emerge along different paths and thus become distinct. It is the band of distinct colours that we see in a spectrum.

Magnetic Field Lines Around a Bar Magnet

Fleming’s Left-Hand Rule

Electric Circuits (Series and Parallel)

Image Formation by Convex Mirror

A ray parallel to the principal axis, after reflection, will pass through the principal focus in the case of a concave mirror or appear to diverge from the principal focus in the case of a convex mirror.

A ray passing through the principal focus of a concave mirror or a ray which is directed towards the principal focus of a convex mirror, after reflection, will emerge parallel to the principal axis.

A ray passing through the centre of curvature of a concave mirror or directed in the direction of the centre of curvature of a convex mirror, after reflection, is reflected along the same path. The light rays come back along the same path because the incident rays fall on the mirror along the normal to the reflecting surface.

A ray incident obliquely to the principal axis, towards a point P (pole of the mirror), on the concave mirror [Fig. 9.6 (a)] or a convex mirror [Fig. 9.6 (b)], is reflected obliquely. The incident and reflected rays follow the laws of reflection at the point of incidence (point P), making equal angles with the principal axis.

Image Formation by Concave Mirror

New Cartesian Sign Convention for Spherical Mirrors

Why Learn Class 10 Science Diagrams 2025?

In the CBSE Class 10 Science Syllabus, the diagrams are more than illustrations; they’re an important scoring section. The CBSE board offers stepwise marking for the diagrams. From simplifying concepts to answering presentations clearly, here is why the diagrams for class 10 science are important.

Improves Visualisation and Concepts Reinforcement

Difficult concepts like the human digestive system, neurones, or magnetic field lines can be simplified and easier for students to understand. Some topics, like refractions, prism diagrams, or electric circuits, become clear via the diagrams. Visualisation retains longer, creating a mental image, thus helping in recalling the concepts faster in exams.

High Weightage in Exams

The carbon cycle, the human eye, and the brain frequently appear in the CBSE board exams. Specific marks are allocated for the diagrams, sometimes the stepwise marking for diagram questions. There is also a high chance that direct questions like "Draw and label the human brain” or Explain the concept of an electric circuit using a diagram are common.

Improves Answer Presentation

A neat and labelled diagram drawn correctly can secure complete marks or partial marks in case the explanation is asked. The well-drawn diagrams easily catch the attention of the examiner and also reflect the understanding of the topic.

Emphasis Important Topics

To cover the topics with high weightage in board exams 2025, practising important diagrams for class 10 science is necessary. These diagrams are directly linked to the CBSE Class 10 Science Syllabus; topics like Life Processes, Light & Electricity, and Periodic Classification are important.

Time Management in Exams

Drawing diagrams is faster and easier than writing lengthy answers most of the time. Sometimes writing the exams needs to be engaging too, and switching between the answers and diagrams can perfectly achieve the task. They often serve as additional explanations in the case of the long question answers.

How to Learn Class 10 Science Diagrams for 2025 Boards?

Well, you might understand the importance of the diagrams for class 10 science, but how can you start practising these diagrams? Below, you’ll find the strategy on how you can start with the important diagrams for class 10 science.

Identify the Important Diagrams.

Start by identifying the diagrams that are frequently asked in exams. These are usually from NCERT textbooks and include:

Biology: Human digestive system, brain, heart, eye, nephron, and the carbon cycle.
Physics: Ray diagrams (mirrors and lenses), magnetic field lines, electric circuits, and refraction through a prism.
Chemistry: Atomic structures, electrolysis, and experimental setups like the preparation of hydrogen gas.

Stick to NCERT

Most of the diagrams in your exam will be based on the NCERT syllabus. Use the diagrams in your textbook as a reference to practice. You can also look at previous year’s question papers to see which diagrams are commonly asked.

Practice Often

Practice is the key to mastering diagrams. Set aside time to draw the important ones regularly. Start with simple diagrams and work your way up to more detailed ones. Repeating the same diagrams will help you remember them during the exam.

Keep Them Neat and Labelled

Use a sharp pencil for neat lines.
Label all parts clearly with straight lines and proper arrows.
Write labels in the same direction to keep your work clean and organised.

Understand the Concept Behind Each Diagram

Don’t just memorise diagrams–understand their purpose and how they work. For example, know how light bends through a prism or why certain parts of the heart are structured the way they are. This will help you explain them better if needed.

Learn Specific Tricks for Each Subject

Physics: Use tools like a ruler for straight lines in ray diagrams or circuits. Learn the standard angles for reflection and refraction.
Biology: Pay attention to proportions in diagrams of the human body. Curved structures like the digestive system require light strokes.
Chemistry: Be precise when drawing molecular structures or lab setups. Accuracy matters here.

Use the Right Tools

Always use a good pencil, eraser, and ruler for straight lines. If allowed, use coloured pencils to highlight important areas like veins or magnetic fields, but keep it simple.

Solve Previous Year's Papers

Practice drawing diagrams under exam-like conditions using the Previous Year Papers Science Class 10. Time yourself to ensure you can complete them quickly and accurately.

Diagrams are a vital part of Class 10 Science, helping you understand concepts better and score higher in your CBSE board exams. They simplify complicated ideas, make your answers look well-organised, and often secure full marks when drawn neatly and accurately.

By practising regularly, focusing on key diagrams from the NCERT syllabus, and understanding their underlying concepts, you can gain confidence and perform well in your exams. Remember, a well-drawn diagram speaks louder than a paragraph, so make it your strength and use it to ace your science exam!