lab 1 - scientific investigation

Question 1

what is the purpose of observation

Answer 1

observation of natural pattern or event leads to the formation of a question

Question 2

what is a hypothesis

Answer 2

proposed explanation of a phenomenon, pattern or a set of observations that is both testable and falsifiable

can never be proven (only reject or fail to reject)

Question 3

what is a null hypothesis

Answer 3

no effect of treatment or no difference between control and experimental groups

Question 4

what is an independent vs dependent variable

Answer 4

independent = manipulated (cause of observed results)

dependent = measured (effect of manipulations)

Question 5

what is the control vs experimental treatment

Answer 5

control = confirms experimental setup doesn’t influence the dependent variable

experimental = demonstrate if independent variable has an effect

Question 6

what is replication

Answer 6

repeat experiment multiple times under the same conditions to obtain reliable results

Question 7

what is the sample mean vs population mean

Answer 7

sample mean = sum of all individual measures in the treatment divided by the number of measurements in the treatment

population mean = from whole population on earth - estimated by sample mean

Question 8

what are three reasons for variability in data

Answer 8

1. measurement error
2. individual organisms within a population are all slightly different
3. sample represents a small portion of the entire population of organisms (only an estimate of how the population responds to treatment)

Question 9

how can variability be reduced

Answer 9

increasing sample size
carry out multiple replicates of an experiment

Question 10

what does standard error of the mean determine

Answer 10

variance in data (large = low confidence, small = high confidence)

more measurements = smaller SEM

variability in numerator
sample size in denominator

Question 11

what is the importance of SEM bar overlap

Answer 11

overlap = likely similar results
no overlap = likely different results

DON’T say significant

Question 12

what is a theory

Answer 12

so much supportive evidence behind a hypothesis that one could consider it “proven”