Unit 0 Flashcards
Experimental Design
Independent Variable
X-axis, what you change on purpose in the experiment (ie. time)
Dependent Variable
Y-axis, what you are measuring & observing (ie. something is changing depending on the amount of time)
Null Hypothesis
Nothing changes
Alternate Hypothesis
Something changes; there is an effect or difference that we can prove & support with evidence
Postive Control
Something you already know works to prove your claim (ie. if testing if a new medication lowers blood pressure, use a drug that we know can already have this effect to make sure the design is good to go!)
Negative Control
When you expect no effect, because you take out the variable you are testing (ie. giving someone a placebo medication, it shouldn’t have any effect on the actual medication’s actions)
Error Bars
If they OVERLAP, they are not significant
Graphs
Use BAR GRAPHS for categories & different groups, use LINE GRAPHS for continuous data, like time
Rate
How much something changes over time and how fast it happens, rate = (initial value - final value) / (final time - initial time)
Mean
Add values, divide by amount
Chi Square
You can fail to reject the null hypothesis when the chi square value is less than the critical value (this means that there is not enough evidence to suggest a difference)
Critical Value
Find the degrees of freedom and look at it on the chart with the P values, it will tell you
Degrees of Freedom
Amount of categories -1
Law of Probability
MULTIPLY the probabilities of 2 things when you are asked the probability of them occurring together; ADD the probabilities of 2 things when you are asked the probability of either one occurring
Hardy Weinberg
P is the frequency of the dominant allele, Q is the frequency of the recessive, and P + Q = 1; P^2 is homo dominant, 2PQ is hetero, Q^2 is homo recessive
Growth Rate
Birth rate - death rate
Exponential Growth
P = Se ^(rt)
P is the total population over time
S is the start population
R is the rate of growth
T is the amount of time
Logistic Growth
Will be on your sheet; basically grows rapidly and eventually slows down
Simpson’s Diversity Index
You take each number of individuals for each species, and divide by the total number to get decimals; then you take each decimal number and times it by itself; then you add up all of the new numbers; essentially the smaller the end number is, the greater the biodiversity.
Water Potential
Goes from high (pure water & less negative) to low (with solutes & more negative)
