CHAPTER 3

CELLS: THE LIVING UNITS

1. Briefly describe interstitial fluid.

2. Define selective permeability and explain how selective permeability is affected when the plasma membrane is severely damaged.

3. Explain the mechanism of the following and state whether each is an active or passive process:  diffusion, osmosis, filtration, active transport, exocytosis, and two forms of endocytosis (phagocytosis and bulk phase endocytosis).

4. Define tonicity.  Differentiate between isotonic, hypotonic and hypertonic solutions.  Explain the effect on a living cell when it comes into contact with each solution (include the terms crenate and lyse).  Be able to solve tonicity problems similar to the practice problems given to you on p. 6 & 7 of this packet.

5. Describe and demonstrate the proper technique for the care and operation of a microscope.

The following objectives were covered in your college biology prerequisite course.  Although this information will not be included on the exam, you will need to understand it to succeed in Biology 204.  We advise you to review in Chapter 3 any of these concepts which you do not have full confidence.

•   Describe the structure of the plasma membrane.  State the functions of proteins within the plasma membrane.  You will not need to distinguish between integral and peripheral proteins.  Define the glycocalyx and state its function.  Describe the general structure and function of microvilli.

•   Differentiate between active and passive processes in moving substances across the plasma membrane.

•   State the function of each of the following organelles:  mitochondria, ribosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, Golgi apparatus, lysosomes, nucleus, nucleoli, and chromatin.

•   Briefly describe the process of protein synthesis.  Include in your description the significance of transcription and translation.

•   Name the molecule that is broken down inside the mitochondria.  Name the molecules that mitochondria form as a result of this catabolism.

•   Discuss the functions of the cytoskeleton.  Differentiate between the functions of two components of the cytoskeleton, the microtubules and microfilaments.  Describe the composition of centrioles.

•   Define cilia and flagella and differentiate between their functions.  State which human cells have flagella.  Know that cilia and flagella are composed of microtubules.