Practical Guide to Zoology: Study Guide - T. A. Dauda 2014

General rules and some recommendations

RECOMMENDATIONS FOR INSTRUCTORS

1. Laboratory sessions in zoology are conducted in groups of 12–15 students. If a group is larger, a teaching assistant should be provided.

2. When Setting up student workstations, arrange the desks so that the instructor can easily reach each student without disturbing their peers. Each workstation must be well-lit, with a light intensity on the desk surface of at least 50 lux.

3. Most dissections of invertebrates and small vertebrates are performed in galvanized iron dissecting trays. The standard tray size is (16-20)×(25-28) cm. It is advisable to paint the trays with light-colored enamel. A pair of clips is attached to the bottom to prevent the wax lining from floating. The wax mixture is prepared using ordinary beeswax combined with rendered lard in a 4:1 ratio. The mixture is melted over heat, and a small amount of Dutch lampblack is added. After vigorous stirring, the hot mixture is poured into a pre-warmed tray. Once or twice a year, the wax layer should be scraped off, re-melted, and re-poured.

4. High-quality work requires sharp cutting instruments and forceps; therefore, it is essential to ensure regular sharpening and honing of all tools.

5. The only way to prevent disruptions in the supply of Materials for laboratory classes is to draft a schedule of specimen collection in the spring for the upcoming academic year. Significant assistance can be gained by opportunistically gathering materials during summer field practice, research expeditions, and other fieldwork.

RECOMMENDATIONS FOR STUDENTS

1. Before beginning your work, make sure you are seated comfortably. Keep your elbows on the desk while working.

2. Never remove any part of the specimen under study until you have positively identified what it is.

3. Hold the scalpel and forceps much as you would hold a pen. A razor must be held with a firm, steady grip. Never press down with a scalpel or razor—always use a slicing motion. Keep the Tissues being dissected under slight tension. Perform the most delicate Procedures by holding a dissecting needle in each hand.

4. Do not be afraid to get your hands dirty, otherwise you will never truly master the subject. In many instances, you will need to handle the specimen directly.

5. Strive to draw as much as possible. Dedicate a separate page in your laboratory notebook to each drawing, centering it on the page. Always use a sharp pencil. First sketch the overall outline of the specimen, and only then proceed to the details. Learn to maintain accurate proportions. It is helpful to color-code a given organ system using a single consistent color.

6. A biologist is obligated to know the international language of science—Latin nomenclature.