Biology 9700 Practical Notes -

A scale fitted inside the microscope eyepiece. It features arbitrary units (epu) that do not change physical size when you switch lenses.

) and boil for 2 minutes to hydrolyze glycosidic bonds. Neutralize with sodium hydrogencarbonate ( NaHCO3NaHCO sub 3 ). Re-test with Benedict's reagent. Serial vs. Simple Dilutions

Add equal volumes of Benedict's reagent and the sample. Heat in a water bath at 80–100°C for 5 minutes. A color change from blue to green, yellow, orange, or brick-red indicates a positive result.

Decrease intervals between concentrations/temperatures tested. biology 9700 practical notes

). Ensure points are accurate to within half a small square.

Use scissors or a scalpel to cut a small sample of tissue, peeling away or cutting a very thin layer of cells. The preparation method must ensure samples are thin enough to allow light to pass through. Place the sample onto a slide, add a drop of water if needed, apply appropriate stain, and gently lower a coverslip.

Enzyme concentration (varied via serial dilution). A scale fitted inside the microscope eyepiece

Suggest using a colorimeter for color intensity, a thermostatically controlled water bath for temperature stability, or increasing the number of intermediate concentrations for a better trend line. 5. Critical Variables Independent Variable: What you change (e.g., pH). Dependent Variable: What you measure (e.g., volume of gas). Control Variables:

V1=2%×10 cm310%=2 cm3 of stock solutioncap V sub 1 equals the fraction with numerator 2 % cross 10 cm cubed and denominator 10 % end-fraction equals 2 cm cubed of stock solution of distilled water to reach the target volume.

Measure fluids using accurate graduated pipettes or digital micropipettes. Quantifying Apparatus Uncertainty Neutralize with sodium hydrogencarbonate ( NaHCO3NaHCO sub 3

Every column heading must include the quantity and SI unit, separated by a slash (e.g., "Mass / g").

To minimize the impact of experimental uncertainty, design your experiments around larger overall quantities or volumes when possible.

For Paper 5, if you are given a table of results and asked to analyze the trend, do this: