130 likes | 257 Views
Cell organization. Viruses. What is a virus? Nonliving Particle Core of hereditary material (DNA) Protein coat Viruses can only reproduce inside a living cell. How are viruses classified ?. Active Viruses: Attach Invade Copy Release Destroys a cell as soon as it enters it.
E N D
Viruses • What is a virus? • Nonliving Particle • Core of hereditary material (DNA) • Protein coat • Viruses can only reproduce inside a living cell
How are viruses classified? • Active Viruses: • Attach • Invade • Copy • Release • Destroys a cell as soon as it enters it
How are viruses classified? (continued) • Latent Viruses: • Attaches, • Becomes part of genetic material, • Divides with cell, • Leaves genetic material and becomes active • Virus can become active and destroy host cell at any time • What is a vaccine? • Preventative made from damaged virus particles that can’t cause disease anymore
Section 3: Microscopes and Cell Theory • Simple Microscope: Magnifying glass • Compound Light Microscope: lets light pass through an object and then through 2 more lenses, magnifying even more • Electron Microscope: use a magnetic field to bend beams of electrons (only dead tissue/cells)
Some important dates: • 1665: Robert Hooke slices a cork and looks at it under a microscope, notices little boxes = cells • 1838: Matthias Schleiden studies plant parts and concludes that all plants are made of cells • 1839: Theodor Schwann says the same thing about animals • 1850’s : Rudolph Virchow hypothesizes that cells can only come from other cells
Cell Theory: • 1. All organisms are made up of one or more cells • 2. Cells are basic unit of structure and function in all organisms • 3. All cells come from cells that already exist
Prokaryotic cells: have no membrane around their nuclear material • Examples: bacteria and cells that form pond scum • Eukaryotic Cells: has a nucleus with a membrane around it • Examples: Animal and plant cells
Animal cells are like a huge factory, all parts working together: • Cell Membrane: outer layer of the cell that allows certain materials in or out (doors/windows) • Cytoplasm: gel-like material filling the cell (air) • Organelles: structures inside the cytoplasm that carry out cell functions
Nucleus: largest Organelle, directs all activity of the cell and contains genetic info for whole cell (office) • Chromatin: hereditary material in nucleus (paperwork) • Endoplasmic Reticulum: folded membrane that moves material around inside the cell (conveyor belt) • Ribosomes: make proteins (factory workers)
Golgi Bodies: package and move proteins out of cell (delivery guys) • Mitochondria: where food molecules are broken down and energy is released (lunch room) • Lysosomes: digest wastes and worn out cell parts (trash men) • Vacuoles: storage areas in cell (closets)
Plant Cells: Very much the same, but there are key differences. • Cell Wall: rigid structure outside the cell membrane that supports and protects the plant cell • Chloroplasts: change light energy into chemical energy (sugar) • Chlorophyll is the chemical that converts energy for plant cells, makes them green
Cell Organization: • Cells • Tissues • Organs • Organ Systems • Organism