Why do we find probability of deviation in biology ? And when can the null hypothesis be accepted

probability is used to predict the chance that an event is likely to occur at a particular chosen level of significance.

Null hypothesis is accepted in biology when the p value is less than 1%, statistically, when the value of p<0.01

Explanation:

Determing the significance level is decided by the researcher, often times, scientists commonly use the 0.05, 0.01, or 0.001 probability levels as cut-off values. For instance, in the example experiment, you used the 1% probability. Thus, P ≥ 0.01 can be interpreted to mean that chance likely caused the deviation between the observed and the expected values (i.e. there is a greater than 1% probability that chance explains the data).

If instead we had observed that P ≤ 0.01, this would mean that there is less than a 1% probability that our data can be explained by chance. There is a significant difference between our expected and observed results, so the deviation must be caused by something other than chance.

her next move would be to use agarose gel electrophoresis to separate the dna molecules of varying length and create a dna fingerprint.