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Cell Biology

Course Outline - 2008Cell Biology Outline

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 DEPARTMENT(s): Dental Medicine

•Overview of Course Topics:•The eukaryotic cell is the fundamental structural

building block of multicellular•organisms and the center for biochemical

processes. In this course you will be introduced to both the structure and function of cells. We will initiate our discussion of the cell by learning some basics of membrane biology. The membrane not only serves as the boundary of the cell but also as the interface for communications with other cells and signaling molecules.

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•COURSE FORMAT:•Total Hours:               Credit Hours:  2•The course is comprised of (2) one-hour

lectures per week. A two-hour laboratory session is conducted weekly to supplement theory with hands-on activities

•COURSE OBJECTIVES:•After successfully completing Cell Biology

the student should be able to:• Comprehend fundamental concepts of

Cell Biology

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Instructors :Dr. Moeen AlborshText bookEssential Cell Biology, Alberts et al., 2nd Edition, 2004

Evaluation :Mid-term Test - -------------- 20% Final Exam - ----- ------------ 45% Laboratory ------------------- 15% Assailment and activates __ 20%

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Outline of Probable TopicsChapter 1IntroductionChapter 2Cell types, Cell componentsChapter 3Cell membranes, Membrane lipids, Membrane proteinsChapter 4Membrane transport, Ion channels, Electrical activity

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Chapter 5 DNA to RNA, The nucleus

Chapter 6RNA to proteins, Endoplasmic reticulum, Golgi, LysosomesChapter 7Mitochondria, Chloroplasts, PeroxisomesChapter 8

Cytoskeleton, Muscle, Axonal transportChapter 9The cell cycleIntercellular contacts and communicationChapter 10Tissues, Extracellular matrix, Stem cells, Cancer

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After you have studied this Course you should be able to:1. Justify considering the cell the basic unit of life.2.Characterize cells with respect to size range, shape, and general features.3.Describe, locate, and list the functions of the principal organelles and be4. Describe the structure of the plasma membrane and list its functions

LEARNING OBJECTIVES

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5- Distinguish between smooth and rough endoplasmic reticulum and describe how ribosomes can be functionally connected with the endoplasmic reticu lum.

6- Explain how the Golgi complex packages secretions and manufactures Iyso somes

7- Describe specific functions of Iysosomes and explain what happens when they become leaky.

8- Justify calling mitochondria the power plants of the cell.

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9- Relate microtubules to centrioles, cilia, and flagella.10- Describe the structure and functions of the nucleus and its contents.11- Summarize how materials pass through plasma membranes, distinguishing between passive and active processes.12-Given concentrations and membrane characteristics, predict the direction of diffusion of solutes and solvents across differentially permeable membranes.

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13- Solve simple problems involving osmosis; for example, predict whether cells will swell or shrink under various osmotic conditions.

14- Describe mechanisms by which cells actively move materials into their cyto plasm; for example, active transport, phagocytosis, and pinocytosis.

15- Describe the stages of a cell's life cycle.

16- Describe the process of mitosis and summarize its significance with respectto maintaining a constant chromosome number

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The cell is the smallest self-suffi cient unit in the body.All cells are surrounded by a mem brane and most contain a nucleus and other organelles scattered throughout the cytoplasm.

Materials pass through the plasma membrane via a variety of pro cesses depending on size and com position of the material

KEY CONCEPTS

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Mitosis is a form of nuclear divi sion that ensures that each new cell will have the identical number and types of chromosomes present in the parent cell.

Each of us began life as a single cell, the fertilized egg. That cell gave rise to the

trillions of cells that make up the com o piex tissues, organs, and systems of the body. Cells are often referred to as building blocks of the body because the body is constructed of cells and substances produced by them.

capable of self-sufficient life .

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Although it consists of many parts, the cell it. self is considered the basic unit of life because it is the smallest part of the body that, given the proper environment, is We might say that the cell is a complete met abolic unit, because it has all the' basic equipment and chemical know-how needed for its own maintenance and growth.

If their environmental needs are met, cells can be kept alive in labora tory bottles for many years. No cell part is 13capa ble of such survival.

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Most cells are microscopic in size. A "typical" cell is about 10 micrometers (about 1/2500 inch) in diameter (see Focus on Cell Size).This means that if you could line up about 2500 typical cells end to end, the resulting cellular parade would measure only 1 inch.Even the egg cells, which are among the largest cells in the human body,are only about as large as a period on this page.

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The size as well as the shape of a cell is re lated to the specific functions it must perform (Fig. 3-1). For instance, the neutrophil, a type of white blood cell, can change its shape as it flows along through the tissues of the body, destroying invading bacteria.Nerve cells have long exten sions that permit them to transmit messages over long distances within the body.

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Sperm cells have long whiplike tails that are used for propulsion. Epithelial cells, which are specialized to cover body surfaces, look like tiny building blocks. Sci entists have developed an impressive array of tools for studying the cell. Some of these are de scribed in the Focus on How Cells Are Studied, pages 88-89.

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The cell is a microcosm of

structure and activity• Early biologists thought that the cell interior con sisted

of a homogeneous jelly that they called protoplasm.

• They recognized only a few struc tures, such as the nucleus, and with their limited tools they had no satisfactory means of exploring the inside of the cell in greater detail.

• With elec tron microscopes and other modern research tools, perception of the world within the cell has been vastly expanded.

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•Scientists have found in side the cell a fabulously dynamic and complex world of ceaseless activity and bewildering chemi cal transformations.

• We are beginning to gain an understanding of what is really going on inside the cells of the body.

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Today, the word protoplasm is no longer used

The jelly-like material outside the nucleus is referred to as cytoplasm (sigh-toe-plazm), and the corresponding jelly-like material within the nu cleus is called the nucleoplasm (new-klee-oh plazm) or karyoplasm .

Scattered throughout the cell are tiny structures called organelles (little or gans) that perform jobs within the cell just as or gans do in the larger body.

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Cytoplasm consists mainly of water (up to 90%) containing amino acids, simple sugars, and other substances used to manufacture larger mol ecules.

Also present are thousands of different kinds of enzymes and molecules used in cellular metabolism, as well as ions that maintain an ap propriate biochemical environment.

Most of the organelles within the cell are en closed by membranes .

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•These membrane-bound organelles effectively partition the cytoplasm into different compartments.

•The membrane acts as a barrier, making it possible for the chemical con tents of the organelle to b~ different from the chemical, environment in the general cytoplasm or in other organelles. These differences in organelle content allow metabolic processes to occur in an orderly, efficient manner.

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The size and shape of cells are related to their functions. fa) An ovum (egg cell) and sperm cells. Ova are among the largest cells; sperm are comparatively tiny .

Note the long tail (flag ellum) used by the sperm in locomotion. By whipping its flagellum. the sperm can move toward the egg.

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fb) Epithelial cells join to form tissues that cover body surfaces or line body cavities.

fe) Among the most highly specialized cells. the nerve cell may live for more than a hundred years without dividing.

Its long extensions are adaptations for transmitting neural messages from one part of the organism to another.