Num8ers biology reference
Complete K-12 Biology Formula Guide
Search 410 biology formulas across microscopy, cell transport, biochemistry, enzymes, photosynthesis, respiration, genetics, evolution, ecology, human body systems, biotechnology, environmental biology, and AP or IB extensions.
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410 of 410 formulas shown.
Frequently asked questions
Does this K-12 biology formula page include all 410 formulas?
Yes. It includes all 410 formulas from the uploaded K-12 biology checklist, grouped by category with formulas, definitions, and variable explanations.
What is the photosynthesis equation?
The photosynthesis equation is 6CO2 + 6H2O + light -> C6H12O6 + 6O2.
What is the cellular respiration equation?
Cellular respiration is C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP.
What is the BMI formula?
BMI equals body mass in kilograms divided by height in meters squared.
What is total microscope magnification?
Total magnification equals eyepiece magnification times objective magnification.
What is surface-area-to-volume ratio?
Surface-area-to-volume ratio equals surface area divided by volume.
What is the water potential equation?
Water potential equals solute potential plus pressure potential.
What is the pH formula?
pH equals negative log base 10 of hydrogen ion concentration.
What is the Michaelis-Menten equation?
Michaelis-Menten uses v = Vmax[S] / (Km + [S]) to model enzyme reaction rate.
What is the Hardy-Weinberg equation?
Hardy-Weinberg uses p squared plus 2pq plus q squared equals 1, with p plus q equals 1.
What is the chi-square formula in biology?
Chi-square equals the sum of (observed minus expected) squared divided by expected.
What is mitotic index?
Mitotic index equals cells in mitosis divided by total cells, multiplied by 100 percent.
What is recombination frequency?
Recombination frequency equals recombinant offspring divided by total offspring, multiplied by 100 percent.
What is population density?
Population density equals population size divided by area.
What is exponential population growth?
Exponential growth follows dN/dt = rN or Nt = N0e^(rt).
What is logistic population growth?
Logistic growth uses dN/dt = rN(1 - N/K), where K is carrying capacity.
What is net primary productivity?
NPP equals gross primary productivity minus respiration loss.
What is Simpson's diversity index?
A common school form is D = 1 - sum of each species proportion squared.
What is cardiac output?
Cardiac output equals heart rate times stroke volume.
What is qPCR fold change?
qPCR fold change is commonly calculated as 2 to the negative delta-delta Ct.