Biology Math: Genetics, Population Growth & Lab Calculations

What you'll build

What you will be able to do

Each lab ends with a concrete result that you build yourself and the checker confirms, cell by cell.

• Count the genotypes of a Tt × Tt Punnett square with EXACT, turn them into probabilities and expected plant numbers, and use the product rule to get the 9 : 3 : 3 : 1 ratio of a dihybrid cross.
• Test whether 640 offspring of a TtYy × TtYy cross fit the 9 : 3 : 3 : 1 ratio: expected counts, the χ² statistic, its p-value and the verdict at the 5% level.
• Count the alleles of a wildflower population, calculate p and q, the Hardy-Weinberg genotype frequencies and expected counts, and estimate the carrier frequency of a recessive condition from its incidence.
• Model a rabbit population on an island for 10 years with exponential and logistic growth, find when it reaches half the carrying capacity and draw both curves in one line chart.
• From plate counts of an E. coli culture you calculate the number of generations, the generation (doubling) time and the specific growth rate in the exponential phase, and forecast a culture after 8 hours.
• Work out the total dilution of a serial dilution series, the CFU per mL from the countable plate, and the live-cell concentration and viability of a yeast suspension counted on a haemocytometer.
• Linearise six initial-rate measurements with the Lineweaver-Burk double reciprocal, fit the line with SLOPE and INTERCEPT, derive Vmax and Km, and draw the plot as a scatter chart with a trendline.
• Compare the plant diversity of two meadows with Simpson's index of diversity (1 − D) and the Shannon index H, and read off how even each community is.