General Zoology Handout
Lab #1
The Microscope
Get a microscope from the cabinet. This is a light microscope. Read Exercise 1. Know the two
types of microscopes (we won’t be using the electron microscope), what each type does and how
they differ. Be familiar with Figure 1-1, and know the following bolded terms: objectives
[(scanning (4x), low-power (10x), high-power (40x)], nosepiece, oculars, stage, arm, base,
substage illuminator (microscope light), coarse-adjustment knob (to be used with 4x and 10x
objective lenses), fine-adjustment knob (to be used with 40x objective lens), iris diaphragm
lever. Get a slide (any slide), put it on the microscope stage and try to focus. Always start on low
power (4x), and once that is in focus move up to the next higher power then the next higher,
focusing each time. This is the easiest way to get into focus what you want to see. If you need
help, ask now. You will be using the microscopes all semester, and you need to know how.
Cell Structure and Division: Exercise 2
Cell organization: Exercise 2a
“Egg cell of sea star”- label the nucleolus, nucleus, nuclear envelope, cytoplasm and plasma
membrane
Mitosis and Cytokinesis: Exercise 2b
Read the section on the cell cycle and mitosis in your manual first to familiarize yourself with the
terminology. Be sure that you know what events take place in the G1, S and G2 phases of
interphase, as well as prophase, metaphase, anaphase and telophase. You should then observe a
whitefish blastula slide under the microscope. These generally have all phases of the cell cycle
represented in them. Do your best to identify all of the phases. Notice that most of the cells seem
to be in interphase.
Meiosis: Exercise 3a (YOU WILL NOT DO THIS EXERCISE BUT THINK ABOUT HOW
MEIOSIS COMPARES T O MITOSIS)
Read the section on meiosis (gametogenesis) in your manual first to familiarize yourself with the
terminology. You are responsible for the following terms: diploid, haploid, homologous
chromosomes, gametogenesis, primordial germ cells, meiosis I, meiosis II, spermatogenesis,
oogenesis, synapsis, crossing over, chiasmata and polar bodies. Be sure that you understand the
process of meiosis. Take a look at the rat testis and find the spermatogonium and sperm cells and
the rabbit ovary and observe an ovum.
1) What are the two primary ways in which mitosis and meiosis differ?
2) List types of organisms that utilize meiosis and those that do not in your notebook.
Cleavage Patterns and Development: Exercise 3b
We will cover the topic of cleavage only briefly. Look at a slide of starfish development, and
identify as many cleavage stages as possible. Pay particular attention to stages A-F in your lab
manual. Especially know the unfertilized egg, fertilized egg blastula and gastrula. I am only
concerned with you becoming knowledgeable about the information on pages 37-38, before the
embryology of the ribbon worm.
Tissues: Exercise 4
Look trough the slides of the following tissues and be able to identify the type:
Epithelial: frog skin, cuboidal epithelium. Note shape of cells and complexity of the layers. Note
the presence of a nucleus or not.
Connective: tendon (dense), areolar, adipose, hyaline cartilage, bone, human and frog blood. Note
the presence of a nucleus or not. Note the Lacuna and Osteon canal in the bone.
Muscle: Identify the three types on the slide. Note the position of the nuclei.