In Biology, as in Real Life, when we want to look at the inside of something, we usually have to cut it open. When one person learns the inside "parts" of something and wants to teach someone else, they often draw a representation and label the parts, and that is how they communicate the names of the parts to someone else.
For instance, if you want to know the parts inside an apple:
This week in lecture and lab we are learning about the terminology related to planes of section. This is a figure from another lab manual that helps to correlate some of the terms, and how they would affect a slice of a structure on a slide.
Next week we are going to start learning how to use the microscope to look at slices of tissue. We will need to use some of the information learned about sections and apply it to microscopic images. This can be a confusing step sometimes - we understand from experience what an apple looks like, but we don't always have a good idea what a "duct" or a "gland" looks like.
So we use artists drawings of the three-dimensional structure to try to understand what we are looking at a slice of under the microscope.
We will take time in lab to understand more about the microscope slides we are studying. The first step, though, is thinking about the planes of section and learning the terms. Good luck!