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

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

Ribosomes: make proteins (factory workers) 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