Interactive Biology Animations for Students | Shikkha Web

Grade 9–11

Mitosis cell division

Watch mitosis happen: interphase, prophase, metaphase, anaphase, telophase and cytokinesis in an interactive animation, with chromosome counting rules and solved problems.

Grade 8–11

Diffusion and Osmosis

Diffusion vs osmosis explained with a live particle simulation: definitions, the difference table, tonicity, plasmolysis, turgor and imbibition, with solved examples.

Grade 7–11

Photosynthesis

Photosynthesis explained: the equation, light-dependent stage, Calvin cycle and limiting factors. Change light, CO₂ and temperature in a live leaf simulation.

Grade 9–11

The human heart: structure and function

See the four chambers, valves, lub-dub sounds and a live ECG in one animated heart. Learn double circulation, the cardiac cycle and cardiac output.

Grade 10–12

Mendelian Genetics

Learn Mendel's laws with a real Punnett-square builder: monohybrid and dihybrid crosses, test crosses, incomplete dominance, blood-type codominance, and sex determination — every ratio computed live.

Grade 11–12

DNA Replication

DNA replication explained: semi-conservative copying, key enzymes, leading vs lagging strand, Okazaki fragments and the Meselson-Stahl proof — in a live simulation.

Grade 9–11

Cellular Respiration

Cellular respiration explained: aerobic vs anaerobic respiration, glycolysis, the Krebs cycle, the electron transport chain and ATP yield. Run the mitochondrion simulation and see the numbers add up.

Grade 9–11

Enzyme Action

What an enzyme is, the active site, lock-and-key vs induced-fit models, how temperature, pH and inhibitors change its rate, and the Michaelis-Menten equation — explore it live in a simulation.

Grade 10–11

The Nerve Impulse and the Action Potential

See a stimulus above threshold (-55 mV) fire an action potential that races down the axon — continuous or saltatory — and release neurotransmitter at the synapse, with the real formulas.

Grade 9–11

The Nephron and Urine Formation

See how a kidney filters about 180 litres of fluid a day yet passes only around 1.50 litres of urine — filtration, reabsorption and the glucose threshold, with the real formulas.

Grade 9–11

Meiosis Cell Division

What is meiosis, what is crossing over, and how is it different from mitosis? Run a 2n = 4 cell through prophase I to telophase II yourself, with worked examples.

Grade 9–10

Digestive System

What is digestion, which enzyme acts where, and how do villi absorb nutrients? Run food's journey from mouth to large intestine yourself, with worked examples.

Grade 8–10

Breathing Mechanism: Inhalation and Exhalation

Watch the diaphragm, ribs and intercostal muscles move air in and out of the lungs. Pressure gauge, spirometer trace, bell jar model and alveolus gas exchange, with solved problems.

Grade 10–12

Protein synthesis

Watch RNA polymerase copy a gene into mRNA, then a ribosome read codons and build a protein. Edit the gene, mutate a base and use the codon table.

Grade 9–12

Blood circulation: double circulation and cardiac output

Watch blood travel from the heart to the lungs, round the body and back, in a live diagram. Pulmonary and systemic circulation, artery vs vein vs capillary, and cardiac output worked examples.

Grade 8–11

Cell structure and organelles: plant cell vs animal cell

See a plant cell and an animal cell side by side. Click the nucleus, mitochondria, chloroplast, Golgi body, ribosomes and more to learn each job. Includes a comparison table, magnification maths and exam questions.

Grade 9–11

Reflex action and the reflex arc

Touch something hot and watch the impulse run receptor, sensory neuron, spinal cord, motor neuron, muscle. Compute reflex time (24.33 ms) and see why pain is felt after you move.

Grade 9–11

The human eye: parts, image formation and accommodation

See how the cornea, iris, lens, ciliary muscles, retina, fovea and blind spot work in a live cross-section. Explore accommodation, myopia and hypermetropia, with solved lens-power problems.

Grade 11–12

Muscle contraction and the sliding-filament model

Watch actin and myosin slide inside a sarcomere. The A band stays 1.6 µm while the I band and H zone shrink; follow the cross-bridge cycle, calcium and ATP step by step.

Grade 9–11

Transport in plants: xylem, phloem and transpiration

See water rise through the xylem and sugar sink through the phloem. Change light, humidity and wind and compute the transpiration rate (54.8 g/m²/h on the default day).

Grade 9–12

Food chain and food web: energy flow and the 10 % rule

Build a food web, remove a species and watch the knock-on effects, then run the 10% rule on an energy pyramid (10,000 kJ of producer energy leaves just 1 kJ at the top).

Grade 11–12

Population growth: exponential and logistic curves

Drag r and the carrying capacity K and watch exponential and logistic curves diverge. With r = 0.40 per hour and K = 1,000, a culture doubles every 1.73 h and levels off near K.

Grade 11–12

Natural selection: peppered moths and the sooty tree

Slide the soot level and watch birds pick off the more visible moths. With 80 % soot and 40 % selection, dark moths climb from 10 % to 90 % of the moths in 15 generations.

Grade 10–12

Immune response: primary and secondary antibody response

Compare a vaccinated and an unvaccinated person on one antibody graph. In this model memory cuts the wait for protection from 8.1 to 2.5 days and raises the peak 5.1 times.

Grade 10–12

Pollination and fertilisation

Follow pollen from anther to stigma, down the pollen tube and into the ovule. Watch double fertilisation make the 14-chromosome zygote and 21-chromosome endosperm, then seed and fruit.