Objectives
From this lab, students will gain an understanding of the parts and usage of both the dissecting and compound microscopes. They will also be able to set up a wet mount, apply a biological stain, and calculate total magnification for the microscope. At the end of lab, students will leave with a broader view on how microscopes are used and can be used to examine organisms or monitor ecosystems.
Materials
· Compound microscopes
· Dissecting microscopes
· Lens paper
· Microscope slides
· Coverslips
· Prepared slides for observation via compound microscope
· Transfer pipet
· Algae suspension
· Paper towels
· Stain for the slides
· Specimens for observation via dissecting microscope
· Photomicrographs for observation
Introduction
The introduction will consist of an explanation of the different types of microscopes, the parts of the compound microscope, how to properly handle a microscope, and common microscopic organisms, such as bacteria and parasite eggs. I plan on elaborating on each part of the microscope, the differences between a transmission electron microscope and a scanning electron microscope, and terms, such as magnification, total magnification, field of view, and parfocal.
Procedures
The lab will start off with teaching assistant going over last week’s allelopathy results and then move into my lecture over microscopes. After an explanation of the equipment, proper handling and usage of the equipment, and discussing how the lab will run, I’ll give a demonstration over the preparation a wet mount and staining a slide. This will most likely take up to twenty minutes. From there, the students will follow their lab manuals and begin the lab. They will start with Part A: The Compound Microscope, move to Part B, then Part C. I will be almost constantly walking throughout the class, helping students, answering questions and asking thought provoking questions on their work. Essentially this portion will take most of the lab period, about one hour.
Review and Discussion
As students complete their workbooks, I will walk around the room and ask if they saw anything of interest in their microscopes and discuss how the microscope has influenced the organism they saw. I will also check on their work individually as they come up to the front to be checked off and ask them questions pertaining to the subject to see if they have achieved a proper understanding on the parts and uses for microscopes.
Assessment
Students will be evaluated based on correct workbook answers for pages 73–81 and their understanding as I ask them about what conclusions they have made at the end of lab. Questions could include an inquiry as to how and why they achieved a particular answer in their workbooks and what they saw through their microscopes. I will remind them that if they need extra help on this subject for the quiz, they should do the review portion at the end of the lab in the workbook.
Resources
Tremblay, M. N. 2009. Environmental Biology Laboratory: Manual + Workbook. Caché House, Inc., Eden Prairie, MN.
