Lab
1 - Objectives
The following list contains all the objectives that should be met for the
first lab in Biology 203.
1. Microscope
Be able to identify the following parts of the microscope
- eyepiece
- scanning lens
- low power lens
- high power lens
- oil
lens
- fine focus know
- course focus know
- condenser
- condenser
adjustment knob
- iris diaphragm adjustment knob
- mechanical stage
knobs
2. Learn the following slides. Only the underlined structures will be on
the lab exam. Check with your instructor to make sure you are identifying
the correct structures.
Connective Tissue
- Human Blood Tissue Look at the slide with the scanning lens
and use the course focus knob to focus on blood cells. At this level, the
cells are very small and faint. Once you have focused on the cells, turn
to the low power lens. Focus again, but this time, use only the fine
focus knob. Once you have found the cells, turn to the high power lens
and focus again with fine focus knob. At this point, you should see many
individual red blood cells which are light pink, disc-shaped, and
without a stained nucleus in the center. Move the slide around with the
mechanical stage knobs to find individual darkly stained cells among the
red blood cells. This will be either a neutrophil,a
lymphocyte or a monocyte(these are the three most common types
of white blood cells). Use the pictures in your textbook (fig.19.6; pg
562) to identify these three cell types. Note the they can be
distinguished by the shape of their nucleus. After finding all 4
cell types, return to scanning power lens and place slide back in tray for
use by another student.
- Finger joint slide. On this slide, you should be able to identify
hyaline cartilage. See page 110 from your book, but keep in mind
that the figure is magnified over 500 times. You should also be able to
identify chrondrocytes, lacuna, and the matrix.
- Areolar Tissue Slide. In addition to identifying areolar
tissue, be able to identify the thin, string-like elastic fibers
and the mast cells. Also, identify the collagen
fibers and fibroblasts. The mast cells are look larger than
the fibroblasts, stain dark because they contain granules of histamine,
and are less numerous. The fibroblasts appear small because the
cytoplasm does not stain (thus, you see only the nuclei). The collgen
fibers are the strands which are thicker and less numerous. See page 106
from your text.
- Dense Regular Connective Tissue. This slide contains and
outer surface of the testis. The pink, outer layer is composed of the
dense regular connective tissue. Identify collagen fibers and
fibroblasts. See page 109 from your text.
Epithelial tissue
- Trachea slide. This slide shows the inner surface of the trachea
(windpipe). The upper edge of this section represents the ciliated
pseudostratified columnar epithelium. Also, identify indiviual
columnar cells, goblet cells, and cilia. See page 98 of
text.
- Section from tongue and/or lip. This slide represents the surface of
the tongue or lip and thus shows stratified squamous epithelium.
See page 99 of your text.
- Gallblader slide. This slide contains a section from the gallbladder
which represents simple coumnar epithelium. See page 98 from your
text.
You will be held respoinsible for all these objectives on the first lab
practical.