Lab 1 Histology - Biology E-65C Lab #1 HISTOLOGY: THE FORM...

Biology E-65C Lab #1
HISTOLOGY: THE FORM AND FUNCTION OF TISSUES
Objectives:
1. To gain an appreciation of tissue types in terms of their functional significance
2. To gain experience with the use of a compound microscope
Reading
Lab Manual – pages 4 – 43
INTRODUCTION
Anatomy is the branch of science that addresses the external form and internal
organization of organisms. The architectural principles upon which living organisms are
built are of premier importance as is the understanding of the structural basis for the
functioning of the various parts. Developmental mechanisms are also of fundamental
importance.
We will study two subdivisions of anatomy in lab; gross anatomy and microscopic
anatomy or histology . You will become acquainted with gross anatomy in the two
skeletal labs. In contrast to gross anatomy, histology involves the examination of the
various structures too small to be seen with the naked eye. Obviously, the successful
study of small structures requires refined optical systems and other ancillary techniques.
In this lab, you will observe normal human tissue under the compound microscope.
Your TF will provide a hands-on tutorial for the particular model of microscope you will
find in your lab room. Each pair is provided a box of microscope slides. Please handle
them with care. You should keep the cover on the slide box as much as possible; stains
fade in the light and prolonged exposure will result in deterioration of the specimen.
Remember as you study the slides that your goal is to be able to recognize and give a
major characteristic for each of the various tissue types. You should make sketches or
notes of your observations. You will then apply what you have learned about basic tissue
types and will identify specific tissue types on organs provided in lab. Spend no more
than 7-8 minutes per slide if you want to get through them all.
Exercise 1 - Histology
A helpful hint: Preparations of tissues can make determinations of cell shapes difficult.
A good rule is to use the nucleus as the monitor of cell shape; nuclear morphology often
reveals cellular morphology. An example: oval nucleus = columnar cell.
TECHNIQUES OF PREPARATION
This outline is provided strictly so you will gain an appreciation of what tissues are
subjected to in the production of prepared slides.
Preparation of Histological Specimens
1) Fixation . Chemical fixatives (such as various aldehydes) are applied to a specimen.
Fixation causes denaturation of the cross-linkages of proteins, prevents autolysis by
autosomes, and kills bacteria and viruses.
2) Dehydration. The sample is placed into successive baths of alcohol of increasing