The purpose of this lab is for you to gain familiarity with cell structure and function. You will investigate different cell types, and learn how to tell them apart. For each cell you will also learn how its structure provides information as to what it does. Finally, you will learn how cells can work together as a tissue to provide multicellular organisms with specific functions.

Learning Objectives:

1. Gain familiarity with the appearance of cells.

2. Understand the differences between prokaryotic cells and eukaryotic cells.

3. Understand the differences between animal cells and plant cells.

4. Learn that cell types differ based on both their structure and their function.

5. Learn about tissue organization for specific functions.

6. Understand dynamic qualities of cells.

Cells are the smallest items that we can still call living units. Our bodies are each made up of approximately 100 trillion cells! That means that each cell must be pretty small. Some organisms are made up of only one single cell. These unicellular organisms are also rather small. We will be using the microscopes today in order to see individual cells from our bodies, plants, and fish. Some of the cells we will see will be spread out individually, others will be within tissue sections containing numerous cells, still others will be within layers of tissues, and others will be moving cells.

You may have already learned in lecture that there are two different types of cells: prokaryotic and eukaryotic cells. You will see both types of cells today, but we will spend most of our time on eukaryotic cells. In addition, although you are learning about many parts of eukaryotic cells in lecture, we will only focus in lab on those cell components that can be seen with a light microscope. Look at Table 1 to understand which parts of the cell typically can be seen with a light microscope and which cannot.

Eukaryotic cell components typically visible with a light microscope	Eukaryotic cell components typically not visible with a light microscope
· Cell membrane (only visible as an edge to the cytoplasm) · Cytoplasm · Nucleus (& nucleolus) In plant cells only: · Chloroplast · Amyloplast · Chromoplast · Storage vacuole · Cell wall	· Endoplasmic reticulum (smooth and rough) · Golgi apparatus · Ribosomes · Mitochondria · Lysosomes · Cytoskeleton

Table #1: Visible cellular components when using the compound light microscope.

Why is it important to understand which components are visible? Because you will be looking at these cells today, and based on only what you see, you will be able to distinguish a great variety of cell types. Also, based on only those organelles and structures you see, you will be able to infer the function of each of these cells.

Cell Functions:

In a multicellular organism, the cells have to work together to provide the organism with all of its functions. Therefore, some cells are specialized for particular functions; for example, some cells are especially good at storing materials, while others are good for motility. However, in a unicellular organism, all of the organismal functions must be carried out by a single cell! This is quite a challenge, but these unicellular organisms are really well designed to do this. Today you will see cells of one type of unicellular organism, bacteria, and the rest will be cells from multicellular organisms. Later on in the semester you will get to view many other interesting unicellular organisms in the Protist Lab.

Table of Contents:

Introduction (on this page)

Exercises:

Introduction:

Last changed: January 21, 2007