Eukaryotic Cell Structure

Essential Questions  What are the functions of the major cell structures?

Organelles  “Little organs”  Specialized structures of the cell  Each organelle has unique functions  These organelles allow the cell to function properly

Organelle Groups  Cell biologists divide organelles into three groups based on their location Nucleus: nucleolus, chromatin, nuclear envelope Cytoplasm: mitochondria, vacuole, Golgi apparatus, centrioles, lysosomes, ribosomes, chloroplasts, endoplasmic reticulum Surface: cell membrane, cell wall

Nucleus  1. Nucleus Control center of the cell Contains nearly all cell DNA  2. Nuclear Envelope Surrounds the nucleus Contains nuclear pores  Allows material to move into and out of the nucleus

Nucleus cont…  3. Chromatin Consists of DNA bound to a protein Condenses to form chromosomes  4. Nucleolus Small, dense region Assembly of ribosomes begin here

5. Cytoplasm  The portion of the cell outside the nucleus  Contains many organelles  Gel-like substance that protects the organelles  Allows movement

Cytoplasmic Organelles  6. Ribosome Small particles of RNA and protein found throughout the cytoplasm Responsible for the assembly of proteins  Follows coded instructions from the nucleus  Numerous in cells active in protein synthesis

 Endoplasmic Reticulum (ER) Site where lipid components, proteins and other materials are exported from the cell 7. Rough ER  Involved in the synthesis of proteins  Ribosomes are found on its surface 8. Smooth ER  Contains collections of enzymes Synthesis of membrane lipids Detoxification of drugs

 9. Golgi Apparatus (Golgi Bodies) Proteins in the rough ER move next into the Golgi Apparatus It modifies, sorts, and packages proteins for storage or secretion Ships proteins to their final destination

 10. Lysosomes Small organelles filled with enzymes “clean up crew” Digestion, or breakdown, of lipids, carbohydrates, and proteins so the rest of the cell can use them Removes dead organelles

 11. Vacuoles Saclike structures that stores materials Plant cells: the vacuoles is a single, large central organelle filled with liquid  Allows for support of leaves and flowers Help maintain homeostasis Also found in some animal cells

 12. Mitochondria Power house of the cell Responsible for providing the cell with energy  Converts stored energy in food into compounds that the cells can use Contains its own DNA  Some scientists believe that mitochondria, at one point, may have been a prokaryotic cell

 13. Chloroplasts Only found in plant cells Capture energy form sunlight and convert it into chemical energy  This process is called photosynthesis  Contains chlorophyll Gives plants its color

 14. Centrioles Come from structures called microtubules Located near the nucleus Help to organize cell division Only in Animal Cells

15. Cytoskeleton  A network of protein filaments that help the cell maintain its shape  Also aids in movement Flagellum Cilia

 16. Cell membrane Cell membrane regulates what enters and leaves the cell Provides protection and support  17. Cell wall Main function is to provide support and protection Only in plant cells

TIME FOR A MINI QUIZ!!  Take out a piece of paper.  Fold it in half length-wise (hot dog)  Head one side “Animal Cell” and number it 1-19  Label the other side “Plant Cell” and number it 1-10  Label the organelles to their corresponding numbers as you see them on each slide.  You may use your notes but NOT your books!

Nucleus Cell Membrane Cytoplasm Rough ER Smooth ER Mitochondria Golgi Body Vacuole Lysosome

Nucleus Cell Membrane Cytoplasm Rough ER Chloroplasts Ribosome Mitochondria Golgi Body Vacuole Cell Wall