The World of Cells

Lincoln RobinsonStudent Sample - EDU 221

Dr. Theresa2-27-2008

Cell TheoryIn 1824, Rene Dutrochet discovered that "the cell is the fundamental element in the In 1824, Rene Dutrochet discovered that "the cell is the fundamental element in the

structure of living bodies, forming both animals and plants through structure of living bodies, forming both animals and plants through juxtaposition.“juxtaposition.“

1. all known living things are made up of cells. 1. all known living things are made up of cells.

      2. the cell is structural & functional unit of all living things.2. the cell is structural & functional unit of all living things.

       3. all cells come from pre-existing cells by division. 3. all cells come from pre-existing cells by division.             (Spontaneous Generation does not occur).             (Spontaneous Generation does not occur).

      4. cells contains hereditary information which is passed from4. cells contains hereditary information which is passed from              cell to cell during cell division.               cell to cell during cell division.

      5. All cells are basically the same in chemical composition. 5. All cells are basically the same in chemical composition.

      6. all energy flow (metabolism & biochemistry) of life occurs 6. all energy flow (metabolism & biochemistry) of life occurs               within cells.              within cells.

    A CELL IS THE BASIC UNIT OF LIFE!!!!

http://www.cellsalive.com/cell_cycle.htm

Prokaryotes vs. Eukaryotes Prokaryote:

No nuclear membrane (genetic No nuclear membrane (genetic material dispersed throughout material dispersed throughout cytoplasm) cytoplasm)

No membrane-bound organellesNo membrane-bound organelles

Simple internal structure Simple internal structure

Most primitive type of cell Most primitive type of cell (appeared about four billion years (appeared about four billion years ago) ago)

Eukaryote:

Nuclear membrane surrounding Nuclear membrane surrounding genetic material genetic material

Numerous membrane-bound Numerous membrane-bound organellesorganelles

Complex internal structure Complex internal structure

Appeared approximately one billion Appeared approximately one billion years agoyears ago

Intracellular Organelles Nucleus:

Nuclear membrane:Nuclear membrane:- Surrounds nucleus- Surrounds nucleus- Composed of two layers- Composed of two layers- Numerous openings for nuclear - Numerous openings for nuclear traffic traffic

Nucleolus:Nucleolus: -Spherical shape-Spherical shape -Visible when cell is not dividing-Visible when cell is not dividing- Contains RNA for protein - Contains RNA for protein

manufacturemanufacture

Chromosomes:Chromosomes: - Usually in the form of chromatin- Usually in the form of chromatin

- Contains genetic information- Contains genetic information- Composed of DNA- Composed of DNA- Thicken for cellular division- Thicken for cellular division- Set number per species - Set number per species

(i.e. 23 pairs for (i.e. 23 pairs for human)human)

Intracellular Organelles Cont… Cytoplasm: LysosomeLysosome: :

-Digestive 'plant' for proteins, lipids, and carbohydrates-Digestive 'plant' for proteins, lipids, and carbohydrates

-Transports undigested material to cell membrane for -Transports undigested material to cell membrane for removalremoval- Vary in shape depending on process being carried out- Vary in shape depending on process being carried out

- Cell breaks down if lysosome explodes- Cell breaks down if lysosome explodes

Chloroplast (plant cells only):Chloroplast (plant cells only):

- - A plastid usually found in plant cellsA plastid usually found in plant cells- Contain green chlorophyll where photosynthesis takes - Contain green chlorophyll where photosynthesis takes placeplace

Vacuoles:Vacuoles:

- Membrane-bound sacs for storage, digestion, and waste - Membrane-bound sacs for storage, digestion, and waste removalremoval- Contains water solution- Contains water solution- Contractile vacuoles for water removal (in unicellular - Contractile vacuoles for water removal (in unicellular organisms)organisms)

Intracellular Organelles Cont… Cytoplasm: Smooth and Rough Endoplasmic Reticulum: Smooth and Rough Endoplasmic Reticulum:

-Tubular network fused to nuclear membrane-Tubular network fused to nuclear membrane- Goes through cytoplasm onto cell membrane- Goes through cytoplasm onto cell membrane- Stores, separates, and serves as cell's transport - Stores, separates, and serves as cell's transport systemsystem- Smooth type: lacks ribosomes- Smooth type: lacks ribosomes

- Rough type (pictured): ribosomes embedded in surface- Rough type (pictured): ribosomes embedded in surface

• Ribosomes:Ribosomes:- Each cell contains thousands- Each cell contains thousands- Miniature 'protein factories'- Miniature 'protein factories'- Composes 25% of cell's mass- Composes 25% of cell's mass- Stationary type: embedded in rough endoplasmic - Stationary type: embedded in rough endoplasmic reticulumreticulum- Mobile type: injects proteins directly into cytoplasm- Mobile type: injects proteins directly into cytoplasm

Cytoskeleton:Cytoskeleton:- Composed of microtubules- Composed of microtubules- Supports cell and provides shape- Supports cell and provides shape

- Aids movement of materials in and out of cells- Aids movement of materials in and out of cells

Intracellular Organelles Cont…

Cytoplasm: Mitochondria: Mitochondria:

-Second largest organelle with unique genetic -Second largest organelle with unique genetic structurestructure- Double-layered outer membrane with inner folds - Double-layered outer membrane with inner folds called called cristaecristae- Energy-producing chemical reactions take place - Energy-producing chemical reactions take place on cristaeon cristae- Controls level of water and other materials in cell- Controls level of water and other materials in cell- Recycles and decomposes proteins, fats, and - Recycles and decomposes proteins, fats, and carbohydrates, and forms ureacarbohydrates, and forms urea

Centrioles (animal cells only):Centrioles (animal cells only):- - Paired cylindrical organelles near nucleusPaired cylindrical organelles near nucleus

- Composed of nine tubes, each with three tubules- Composed of nine tubes, each with three tubules

- Involved in cellular division- Involved in cellular division

- Lie at right angles to each other- Lie at right angles to each other

Intracellular Organelles Cont… Cell Surface:

Cell Wall (plant cells only):Cell Wall (plant cells only):

- Most commonly found in plant cells- Most commonly found in plant cells- Controls turgity- Controls turgity- Extracellular structure surrounding plasma membrane- Extracellular structure surrounding plasma membrane- Primary cell wall: extremely elastic- Primary cell wall: extremely elastic- Secondary cell wall: forms around primary cell wall - Secondary cell wall: forms around primary cell wall after growth is complete after growth is complete

Cell Membrane:Cell Membrane:

- Outer membrane of cell that controls cellular traffic- Outer membrane of cell that controls cellular traffic- Contains proteins (left, gray) that span through the - Contains proteins (left, gray) that span through the membrane and allow passage of materialsmembrane and allow passage of materials- Proteins are surrounded by a phospholipid bi-layer.- Proteins are surrounded by a phospholipid bi-layer.

http://www.cellsalive.com/cells/3dcell.htmhttp://www.cellsalive.com/cells/3dcell.htm

Intracellular Organelles Links to other resources:

Cells and Organelleshttp://www.life.uiuc.edu/bio100/lessons/cells_and_organelles.html

The Insides of Cellshttp://kauai.cudenver.edu:3010/0/nutrition.dir/organelle.html

Structures and Function of Organelleshttp://esg-www.mit.edu:8001/esgbio/cb/organelles.html

Why Are There Organelles?http://iip.ucsd.edu/Step/projects95/cellular.Organelles/WHY.HTM

Cellular Organelleshttp://iip.ucsd.edu/Step/projects95/cellular.Organelles/CELLS.HTM

Microfilaments and Microtubules--The Cytoskeletonhttp://www-class.unl.edu/bios201/group6/cytoskel.html

Eukaryotic Cell Membrane or Plasma Membranehttp://www.bio.mtu.edu/campbell/eukaryot.htm

The Nucleus, Nucleolus, Nuclear Envelope, and everything you ever wanted to know about DNA (but were afraid to ask)http://www-class.unl.edu/bios201/group6/nucleus.html

Lysosomeshttp://www-class.unl.edu/bios201/group6/lyso.html

The Rough and Smooth Endoplasmic Reticulumhttp://www-class.unl.edu/bios201/group6/er.html

The Endoplasmic Reticulumhttp://lenti.med.umn.edu/~mwd/back/cell_www/chapter2/ER.html

The Golgi Bodieshttp://www-class.unl.edu/bios201/group6/golgi.html

Centrioleshttp://www-class.unl.edu/bios201/group6/centrio.html

Mitochondriahttp://www-class.unl.edu/bios201/group6/mitochon.html

Blood Cells Blood cells:Blood cells:

Erythrocyte (red blood cells)Erythrocyte (red blood cells) Leukocyte (white blood cells)Leukocyte (white blood cells) Thrombocyte (platelet cells)Thrombocyte (platelet cells)

Originate:Originate: All blood cells are created in All blood cells are created in

bone marrow.bone marrow. Stem cells divide in the Stem cells divide in the

marrow.marrow.

White Blood Cells

Leucocytes:Leucocytes:

Neutrophils 40 - 75 %Neutrophils 40 - 75 %

Lymphocytes 20 - 50 %Lymphocytes 20 - 50 %

Eosinophils 5 % Eosinophils 5 %

Monocytes 1 - 5 %Monocytes 1 - 5 %

Basophils 0.5 %Basophils 0.5 %

Lymphocytes-Make up a large part of the immune defense system.-Make up a large part of the immune defense system.

-Act in response to antigenic stimulation. -Act in response to antigenic stimulation.

-Are found in the bloodstream, lymphatic tissues and organs of the -Are found in the bloodstream, lymphatic tissues and organs of the lymphatic system.lymphatic system.

-Consist of B and T cells, NK cells-Consist of B and T cells, NK cells

B cells initiate Humoral immunityB cells initiate Humoral immunity

Synthesize and secrete antibodiesSynthesize and secrete antibodies

Kill off BacteriaKill off Bacteria

T cells initiate Cell-mediated immunityT cells initiate Cell-mediated immunity

Secrete cytokines Secrete cytokines

Cytolytic T cells automatically kill infected cellsCytolytic T cells automatically kill infected cells

http://www.cellsalive.com/antibody.htmhttp://www.cellsalive.com/antibody.htm

Lymphocytes cont…

-Natural Killer CellsNatural Killer Cells --Lack antigen receptorsLack antigen receptors -Regulate the production of blood cells-Regulate the production of blood cells

B Lymphocytes-All B cell lymphocytes have a specific receptor for specific -All B cell lymphocytes have a specific receptor for specific

antigens.antigens.BCR is the unique protein that helps activate B cells, creates the BCR is the unique protein that helps activate B cells, creates the specific binding sites, and allows B cells to recognize other specific binding sites, and allows B cells to recognize other lymphocytes. lymphocytes.

-Helps neutralize the microbe.-Helps neutralize the microbe.-Activates phagocytes -Activates phagocytes -Macrophages are antigen presenting cells-Macrophages are antigen presenting cells

Present antigens to B and T cellsPresent antigens to B and T cells-Two main types of B cells-Two main types of B cells

Memory cellsMemory cellsFormed from activated B cellsFormed from activated B cellsLonger life, ready to respond to repeated exposure to a particular Longer life, ready to respond to repeated exposure to a particular

antigen.antigen.

Plasma cells Plasma cells Larger B cells that secrete large amounts of antibodiesLarger B cells that secrete large amounts of antibodiesAntibodies bind to microbes making them easier for phagocytes to Antibodies bind to microbes making them easier for phagocytes to

attack.attack.

B Lymphocytes cont…-B cells can encounter the antigen when it is soluble (lymph or -B cells can encounter the antigen when it is soluble (lymph or

bloodstream)bloodstream)

-Naive B cells are throughout the body at all times-Naive B cells are throughout the body at all times -Secreting low levels of antibodies-Secreting low levels of antibodies

-Activated by T cells-Activated by T cells

-Many antigens are T-dependant-Many antigens are T-dependant-Require the combination of B and T cells for “co-stimulation”-Require the combination of B and T cells for “co-stimulation”-Activation of the highest level of antibody production-Activation of the highest level of antibody production

http://www.cellsalive.com/antibody.htmhttp://www.cellsalive.com/antibody.htm

“Medical game-plan”

-Results from initially testing shows three large tumors present.- Each tumor is located within the lymphatic system, specifically on the lymph nodes.

-Results from the blood work showed a decrease in the level of white blood cells, which is usual. The tests showed that the patients platelet level is way down.

-I recommend an immediate platelet transfusion, and to keep a close watch on the status of white blood cells.

-These initial results are leading me to believe you will require stem cell transplant from a matching donor after you undergo radiation and chemotherapy to control the growth of present tumors.

-I am going to create an official report and have all this report reviewed by our medical staff for second opinions. I will also make sure all Doctor’s have received a copy of the results from your blood work and CAT scan.

ReferencesBecker, Kleinsmith, Harden. (2000). Becker, Kleinsmith, Harden. (2000). The world of the cellThe world of the cell. New York: . New York:

Addison Wesley Longman, Inc.Addison Wesley Longman, Inc.

Blood: The river of life. 2001 July. Retrieved April 30, 2007 from the Blood: The river of life. 2001 July. Retrieved April 30, 2007 from the world wide web: http://library.thinkquest.org/C0115080/?c=wbcworld wide web: http://library.thinkquest.org/C0115080/?c=wbc

http://www.cellsalive.com/cells/3dcell.htmhttp://www.cellsalive.com/cells/3dcell.htm

http://www.cellsalive.com/cell_cycle.htmhttp://www.cellsalive.com/cell_cycle.htm