Biology Experiments

Reducing Sugar (Benedict's Test)

Add Benedict's reagent to the food sample and heat. Result: Blue changes to brick-red.

Starch (Iodine Test)

Add iodine solution to the food sample. Result: Red-brown changes to blue-black.

Protein (Biuret Test)

Add sodium hydroxide and copper(II) sulfate to the food sample. Result: Blue changes to purple/violet.

Lipid (Ethanol Emulsion Test)

Shake the food sample with ethanol, then pour into water. Result: Clear liquid turns into a milky emulsion.

Microscopy (Plant/Animal Cells)

Prepare an onion peel or cheek cell slide and view under low and high power (x100 / x400).

Osmosis (Visking Tubing)

Fill Visking tubing with sucrose solution, immerse in distilled water. Monitor mass changes (water moves in, tubing swells).

Growth of Leaf Yeast

Attach leaf discs to agar plate lid, incubate upside down at 25°C, observe circular yeast colonies.

Enzyme Activity / Effect of Temperature & pH

Mix enzyme with substrate at varied temperatures or pH, measure product formation over time.

Immobilized Enzymes

Mix yeast with sodium alginate, drop into calcium chloride to form beads for continuous catalysis.

DNA Isolation (Onion)

Blend onion with detergent and salt, heat, filter, and layer ice-cold ethanol to precipitate DNA.

Photosynthesis (Elodea)

Place Elodea in sodium hydrogen carbonate solution at varying light distances, count oxygen bubbles.

Respiration (Ethanol / Yeast)

Mix yeast with glucose, seal flask for anaerobic conditions, test products using limewater or other tests.

Plant Growth Regulator (IAA)

Germinate cress seeds on treated cotton wool, measure growth to plot inhibition/stimulation curves.

Ecology Fieldwork (Quadrat & Abiotic Factors)

Toss quadrat in ecosystem to measure plant frequency and concurrent abiotic factors like light intensity.