1. 27 Aug. 2012Organelles.ppt1 Cytoplasmic Organelles Organized units of the cytoplasm

2. 27 Aug. 2012Organelles.ppt2 Cytoplasmic Organelles Mitochondrion (-a) Ribosomes Endoplasmic reticulum (ER) Golgi apparatus Lysosomes Peroxisomes Cytoskeleton Centrioles Secretory vesicles Cilium, cilia Nucleus

3. 27 Aug. 2012Organelles.ppt3 Mitochondrion Generates most ATP –"power plant of the cell" Double membrane –outer smooth, sausage- shaped –inner folded with enzymes Contains own DNA, probably evolved from symbiotic bacteria

4. 27 Aug. 2012Organelles.ppt4 Endoplasmic reticulum (ER) Network of membranes enclosing spaces (cisternae) separate from rest of cytosol.

5. 27 Aug. 2012Organelles.ppt5 Endoplasmic reticulum (ER) Rough ER –Associated with ribosomes –Production of proteins for membranes or export (exocytosis, secretion).

6. 27 Aug. 2012Organelles.ppt6 Endoplasmic reticulum (ER) Smooth ER –NO ribosomes, membranes with integral proteins, –Lipid metabolism & synthesis including steroid hormones, –Absorption & transport of fats, –Enzymatic detoxification of drugs, pesticides, etc. (natural & artificial), –Hydrolysis of stored glycogen to glucose, –Storage of Ca +2 ions in muscle cells.

7. 27 Aug. 2012Organelles.ppt7 Ribosomes Very tiny –invisible under light microscope Dense specks of ribosomal RNA Free in cytoplasm or membrane-bound (ER)

8. 27 Aug. 2012Organelles.ppt8 Ribosomes Sites of protein synthesis –mRNA specifies sequence of amino acids –some proteins packaged in vesicles by ER

9. 27 Aug. 2012Organelles.ppt9 Golgi apparatus Series of flat membranous sacs Modifies, concentrates, & packages proteins for secretion, exocytosis Movement to plasma membrane Production of lysosomes.

10. 27 Aug. 2012Organelles.ppt10 Lysosomes Membranous bags of digesting enzymes, Destroy particles taken in by endocytosis and phagocytosis Remove and destroy worn out organelles Removal of excess cells & tissues –"cell suicide" Removal of bone matrix to release Ca +2

11. 27 Aug. 2012Organelles.ppt11 Peroxisomes Resemble lysosomes, but not from Golgi apparatus Enzymes oxidize toxins and remove free-radicals.

12. 27 Aug. 2012Organelles.ppt12 Cytoskeleton Protein "rods," filaments, and tubes running through cytosol Maintain or change shape of cell Move organelles

13. 27 Aug. 2012Organelles.ppt13 Centrioles Clusters of microtubules, usually paired near nucleus –Organize mitotic spindle –Bases (“motors”) of cilia and flagella

14. 27 Aug. 2012Organelles.ppt14 Secretory vesicles Packages of chemicals for export (exocytosis) –hormones –digestive enzymes –sweat –mucus

15. 27 Aug. 2012Organelles.ppt15 Cilium, cilia Short whip-like “appendage” –move material past cell –linings of trachea & bronchi similar to flagellum (longer) on sperm cell

16. 27 Aug. 2012Organelles.ppt16 Nucleus Enclosed in nuclear envelope Residence of chromosomes, DNA Active in synthesis & export of RNA Directs protein synthesis, development of cell