Cell Structure & Function http://koning.ecsu.ctstateu.edu/cell/cell.html

Cell Theory All living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division.

Definition of Cell A cell is the smallest unit that is capable of performing life functions.

Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell Nerve Cell

Prokaryotic Eukaryotic Two Types of Cells Prokaryotic Eukaryotic

Prokaryotic Do not have structures surrounded by membranes Few internal structures One-celled organisms, Bacteria http://library.thinkquest.org/C004535/prokaryotic_cells.html

Eukaryotic Contain organelles surrounded by membranes Most living organisms Plant Animal http://library.thinkquest.org/C004535/eukaryotic_cells.html

“Typical” Animal Cell http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif

“Typical” Plant Cell http://waynesword.palomar.edu/images/plant3.gif

Cell Parts Organelles

Cell Membrane Outer membrane of cell Contains the cell contents Controls what gets in and out of the cell Is selectively permeable http://library.thinkquest.org/12413/structures.html

Nucleus Directs cell activities- the “Control Center” Contains genetic material – DNA Usually the easiest organelle to see under a microscope

ADD THE LABELS

Cytoplasm Gel-like mixture Surrounded by cell membrane

Endoplasmic Reticulum Moves materials around in cell- the “Assembly line or Roads” Smooth type: lacks ribosomes Rough type (pictured): ribosomes attached to surface http://library.thinkquest.org/12413/structures.html

Ribosomes Each cell contains thousands Make proteins Found on RER & floating throughout the cell http://library.thinkquest.org/12413/structures.html

Mitochondria Cellular respiration occurs here to release energy for the cell to use “Power plant” of the cell http://library.thinkquest.org/12413/structures.html

Golgi Bodies Protein “packaging plant” or “shippers” Coats proteins and other materials so they can move different location inside/outside of cell http://library.thinkquest.org/12413/structures.html

Golgi Apparatus

Lysosome The “Clean-up Crew” Filled with enzymes that break apart molecules that are small enough for cell to use Get rid of wastes “garbage disposal” Destroy old cells/organelles; “suicide sacs” http://library.thinkquest.org/12413/structures.html

Lysosomes Tay-Sachs disease occurs when the lysosome is missing the enzyme needed to digest a lipid found in nerve cells. As a result the lipid accumulates and nerve cells are damaged as the lysosome swells with undigested lipid.

Centriole Aids in cell division Only in animal cells Microtubules are also part of the cytoskeleton.

Vacuoles Large central vacuole in plant cells Many smaller vacuoles in animal cells “Storage container” for water, food, wastes, etc. The image is 2D, so it must have been a light microscope or TEM. If the cell is very tiny, then a TEM was used. Otherwise, a strong light microscope could have captured this image.

Plant Cell Features Unique Features of Plant Cells Plant cells have three structures that animal cells lack: a cell wall Chloroplasts Large vacuole

Chloroplast Found in plant cells Capture energy from the sunlight and convert it into chemical energy…PHOTOSYNTHESIS! Green in color because of chlorophyll, a green pigment http://library.thinkquest.org/12413/structures.html

Cell Wall Found in plant and bacterial cells Rigid, protective barrier that provides support Located outside of the cell membrane Made of cellulose (fiber) This is an actual microscopic image. Explain that the colors are added digitally to enhance the different parts.

Quick Review Which organelle is the control center of the cell? Nucleus Which organelle holds the cell together? Cell membrane Which organelles are not found in animal cells? Cell wall, chloroplasts Which organelle helps plant cells make food? Chloroplasts What does E.R. stand for? Endoplasmic reticulum You may choose to delete the answers from the PowerPoint or change the animation so that they come in after all 5 questions are asked in case you want to quiz students individually at the end.

Elodea Cells http://carnegieinstitution.org/first_light_case/horn/lessons/images/chlorop.jpg

Cheek Cells Stained with Methyl Blue Plasma Membrane Nucleus Cytoplasm http://faculty.kutztown.edu/friehauf/science_outreach/cheek_cells_005.jpg