Eight : This is too long and detailed to be in an abstract; it sounds as though it was pulled from the methods and materials section of the paper. The amounts of enzyme do not need to be stated, nor do the pH levels. The number of samples tested do not need to be included either; it is just extraneous information that is not crucial to understanding the experiment as a whole. The information contained in this sentence can be pulled out and rearranged to say that some samples had a constant pH and varying enzyme concentrations and other samples had constant enzyme concentrations and varying pH levels. With the controls and the variables stated you can move on to your results. ( return to Sample 1 )
Suppose we were modeling the behavior of animals, by creating a class hierachy that started with a base class called Animal. Animals are capable of doing different things like flying, digging and walking, but there are some common operations as well like eating and sleeping. Some common operations are performed by all animals, but in a different way as well. When an operation is performed in a different way, it is a good candidate for an abstract method (forcing subclasses to provide a custom implementation). Let's look at a very primitive Animal base class, which defines an abstract method for making a sound (such as a dog barking, a cow mooing, or a pig oinking).