1. Eukaryotic Cell Structure Section 7-3 p.179 -187

2. Group work vs. Cell Parts?

3. Cellular Boundaries Plasma membrane Cell wall – Fairly rigid structure located outside the plasma membrane that provides additional support + protection Composed of cellulose Is not selectively permeable

4. The Nucleus + Cell Control The nucleus is the leader of the eukaryotic cell because… – It contains the directions to make proteins Proteins are needed by every part of the cell Chromatin – Strands of DNA – When a cell divides, chromatin condenses into chromosomes

5. The Nucleus + Cell Control Nucleolus – Organelle within the nucleus that makes ribosomes

6. The Nucleus + Cell Control Ribosomes – Sites where the cell produces proteins according to the directions of DNA Not membrane bound Made of RNA + proteins – To make proteins, ribosomes leave the nucleus + enter the cytoplasm Clear, gelatinous fluid inside a cell – To get to the cytoplasm, ribosomes + translated RNA must leave the nucleus through pores in the nuclear envelope (membrane)

7. From Transcription to Translation

8. Assembly, Transport, + Storage Endoplasmic Reticulum – Site of cellular chemical reactions – Large surface area for work – folds like an accordion to fit in cell

9. Assembly, Transport, + Storage Rough ER – Carries out protein synthesis Proteins made can be used in the plasma membrane, released from the cell, or transported to other organelles Smooth ER – No ribosomes Produces + stores lipids

10. Assembly, Transport, + Storage Golgi apparatus – Flattened stack of tubular membranes that modifies the proteins Sorts proteins into packages called vesicles to be sent to the correct destination

11. Assembly, Transport, + Storage Vacuole – Membrane-bound compartments used for temporary storage – Used to store: Food Enzymes Other materials – Usually not found in animal cells

12. Assembly, Transport, + Storage Lysosomes – Organelles that contain digestive enzymes – Can digest: Excess or worn out organelles Food particles Engulfed viruses or bacteria – Examples: Frog + Human Hand

13. Frog + the Human Hand…

14. Energy Transformers Chloroplasts – Cell organelles that capture light energy + convert it to chemical energy Has a double membrane Made of thylakoids arranged in stacks called grana surrounded by a fluid called the stroma

15. Energy Transformers – Belongs to a group known as plastids, which may store: Starches Lipids Other pigments – Named according to their pigment Contain the pigment chlorophyll, which gives plant stems + leaves their green color

16. Energy Transformers Mitochondria – Organelle in plant + animal cells that transform energy for the cell Has a double membrane Inner membrane is folded for a large surface area for chemical reactions to take place – Energy-storing molecules are produced here May vary in numbers depending on function of cell – Example: a liver cell = 2000 mitochondria/cell

17. Organelles for Support + Locomotion Cytoskeleton – Forms the framework of a cell Composed of microtubules + microfilaments Maintains shape of cell, support of organelles, + allows materials to move within the cell

18. Organelles for Support + Locomotion Centrioles – Organelles found in the cells of animals + protists – Occur in pairs and are made up of microtubules – Play a role in cell division

19. Organelles for Support + Locomotion Cilia – Short, numerous projections (look like hairs) Motion – oars in a row boat/swimmer doing breaststroke

20. Organelles for Support + Locomotion Flagella – Longer projections (looks like a tail) Motion – whips back + forth

22. Comparison of Prokaryotic + Eukaryotic Cells Cell PartFunctionProkaryotic CellEukaryotic Cell Plasma Membrane Maintains homeostasisPresent Cell WallSupports + protects cellPresentPresent (plants) RibosomeMakes proteinsPresent ChloroplastProduces foodAbsentPresent (plants) CytoskeletonProvides internal structure AbsentPresent ERChemical reactionsAbsentPresent GolgiSorts + transportsAbsentPresent LysosomeDigests materialsAbsentPresent (some) MitochondriaTransforms energyAbsentPresent NucleusCell control centerAbsentPresent VacuolestorageAbsentPresent