Because enzymes connect to their substrate through a lock-and-key system, where the shape of the substrate and the enzyme has to fit like puzzle pieces. Then only the enzymatic reaction can occur.
Answer:
The sample size of the animal was too small , not large enough to conclude that the effects of the chemicals on Salamander was the actual cause of toxicity and weight loss.
It is possible that the drop in weight may be as a result of other environmental factors; agitation from background noise and sudden exposure to new environments,, fluctuation in temperature of the surrounding environments , lack of feed supply or others
However, if there was many salamanders available; and most reacted to the chemical exposure in the same way then it can be concluded that, toxicity of the chemical is the causative factor.
Explanation:
It takes 3 bases to make an amino acid
A confounding variable refers to an external effect, which modifies the influence of an independent and dependent variable. This extraneous effect is used to affect the outcome of an experimental design. The confounding variables can ruin the experiment and can generate unnecessary outcomes.
In the given case, confounding variables can be introduced by testing multiple hypotheses at a time and by using distinct kinds of soil in each of the samples.