1 / 29

CYTOLOGY

CYTOLOGY. THE STUDY OF CELLS - STRUCTURE. GENERAL. Cell = Smallest Living Unit Produced by Cell Division or Fertilization Surrounded by Interstitial / Extracellular Fluid Components: Plasma (Cell) Membrane Cytoplasm Organelles. THE PLASMA MEMBRANE.

elina
Download Presentation

CYTOLOGY

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CYTOLOGY THE STUDY OF CELLS - STRUCTURE

  2. GENERAL • Cell = Smallest Living Unit • Produced by Cell Division or Fertilization • Surrounded by Interstitial / Extracellular Fluid • Components: • Plasma (Cell) Membrane • Cytoplasm • Organelles

  3. THE PLASMA MEMBRANE • Phospholipid bilayer: Hydrophobic tails and hydrophilic heads, selectively permeable • Proteins: Peripheral and integral • Enzymes • Receptors • Transport • Anchors • Carbohydrates: Superficial recognition sites

  4. THE PLASMA MEMBRANE cont. • Fluid Mosaic Model (mosaic of floating proteins) • Functions of Plasma Membrane: • Physical Barrier (Selective!) • Regulates Exchange with Environment • Sensitive to Extracellular Environment • Structural Support

  5. THE PLASMA MEMBRANE

  6. CYTOPLASM • Material Between Plasma Membrane & Nucleus • Components • Cytosol (water + nutrients & other solutes) • Organelles (excludes nucleus) • Inclusions (stored materials) • Functions: Site of chemical reactions

  7. ORGANELLES • “Little Organs” • Membranous organelles • Membrane isolates secretions, enzymes or toxins • Non-membranous organelles

  8. NUCLEUS(Membranous) • Double Nuclear Membrane with Pores • Nucleoplasm • Nucleolus • Organelle in nucleus (non-membranous) • Assembles ribosomes • DNA • Chromatin - loose; protein synthesis • Chromosomes - dense, rodlike; cell division

  9. STRUCTURE OF THE NUCLEUS

  10. ENDOPLASMIC RETICULUM (Membranous) • Smooth endoplasmic reticulum (SER) • Synthesis of Carbohydrates, Steroids & other Lipids • Storage (Synthesized Materials or Ca+) • Rough endoplasmic reticulum (RER) • Attached Ribosomes • Protein synthesis for “export” or inclusion in cell membrane

  11. GOLGI COMPLEX/APPARATUS (Membranous) • Structure: • Flattened Membranous Sacs • Function: • Modifies & packages proteins • Source of lysosomes • Renewal/modification of plasma membrane

  12. MITOCHONDRIA (Membranous) • Structure: Double membrane • Function: Production of ATP (95%), cellular energy • Contains DNA • Self-Replicating

  13. MITOCHONDRIA

  14. LYSOSOMES (Membranous) • Structure: Vesicles filled with Digestive Enzymes (“Suicide Bags”) • Function: • Digestion within the cell • Defense • Recycle worn-out cells

  15. Peroxisomes • Membranous sacs of enzymes • Detoxify harmful/dangerous substances • Alcohol • Formaldehyde • Free Radicals

  16. VACUOLES AND VESICLES (Membranous) • Structure: Membranous Sac • Function: Storage, Endocytosis, Exocytosis

  17. FORMATION OF VESICLES

  18. RIBOSOMES (Non-membranous) • Structure: Two subunits (rRNA + protein) • Function: Protein synthesis • Fixed or Free

  19. CENTROSOMES AND CENTRIOLES (Non-membranous) • Centrosome: “Cell center” • Area of cytoplasm • Microtubule formation center • Contains Centrioles • Centrioles: • Microtubules • Form Mitotic Spindle

  20. CYTOSKELETON (Non-membranous) • Network of protein structures • Acts as cell’s “muscles & bones” • Determines cell shape • Supports organelles • Involved in internal transport & cellular movements

  21. CILIA & FLAGELLA (Non-membranous) • Cilia – short, numerous, move substances over free surfaces • Flagella – long, singular, move cell • Microvilli – thin folds of cell membrane, increase surface area to maximize absorption

More Related