what do you try to do in an introduction?

Usually i use the introduction to frame the discussion and introduce the argument. I feel a good introduction also needs to define key terms and at some point introduce the thesis.

What do you try to do in a conclusion?

In a conclusion you need to summarise the arguments you have made in the essay. After you should restate your thesis and draw anything left open to a close.

The article I have chosen to write about is from the magazine Wired. The article discusses whether or not scientists should resurrect extinct species. In the introduction the author sets the background for the article itself. They have a paragraph describing a specific example before switching to discussion of the main point. I feel this is a very effective introduction, partly because of the structure the author has used. Instead of trying to keep the introduction in one paragraph they have split it into three sections. The first gives background, the second is a one line attempt to draw the reader further in, and the third actually explains the science that is behind the article. However, while this may work for a wired article i feel like in academic writing it would be far too lax and so i shall stick with more traditional introduction structures.

article:http://www.wired.com/2015/11/biologists-could-soon-resurrect-extinct-species-but-should-they/