Control tube

What is a control tube? When they say, if you were to set up a control, what would be in it, and what is the significance of a control tube in an experiment?

Thanks for the help :smile:

Reply 1

gyrase

When you say 'control tube' it's probably the type of control in your specific experiment, but normally a control is used to compare your experiment with the effects of having something in it and something out. So say you run an experiment in which your testing the effects of oxygen on photosynthesis, your control would be a trail with no oxygen present and testing rate of photosynthesis. You would then compare this control with the results of having oxygen present on the rate of photosynthesis.

Reply 2

Mos Def

So basically the variable would not be present in our control? And the control just helps us to compare?

Reply 3

Sarah_V

The control helps rule out any other factors that might be affecting the results of your experiment, and is also used as a comparison too.

For example, doctors testing drugs use a placebo on some patients, and the real thing on others. They can then tell if patients are just "making it up" as it were, because those with the placebo, obviously, had no actual drug.

So yes, you wouldn't be using the variable (called a negative control I think), say if you were testing how an enzyme catalyses a reaction, you'd carry out a reaction without any of the enzyme (+ repeats, obviously).