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Diffusion. The Rate of Diffusion is affected by 3 different factors: 1. Temperature 2. Concentration 3. Pressure. Diffusion: The net movement of particles from an area of higher concentration to an area of lower concentration. Due to random movement. Osmosis.
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Diffusion The Rate of Diffusion is affected by 3 different factors: 1. Temperature 2. Concentration 3. Pressure • Diffusion: • The net movement of particles from an area of higher concentration to an area of lower concentration. Due to random movement
Osmosis • Is the diffusion of water through a semipermeable membrane • Movement of water is from an area of low concentration (of solute) to and area of high concentration (of solute)
Hypertonic, Hypotonic, Isotonic • Hypertonic: • A solution with a high concentration of solute Hypotonic: A solution with a low concentration of solutes Isotonic A solution that has the same or equal strengths of solutes in a solution
The Cell • Watch Intro Video • Answer the following questions • What is a prokaryote? • Where did modern plant/animal cells come from? • What is a eukaryote? • http://www.dnatube.com/video/2318/Cell-Biology
The Cell • The Discovery
The Cell Theory 1. All organisms are composed of one or more cells. 2. The cell is the basic unit structure and organization of all organisms. 3. All cells come from preexisting cells.
The Cell There are 2 types of Cells… • Prokaryotes • Eukaryotes http://videos.howstuffworks.com/hsw/23414-cell-cell-characteristics-video.htm
Prokaryotic Cells Cells that DO NOT contain membrane bound organelles (no nucleus) Most bacteria and unicellular organisms
Eukaryotic Cells • Cells containing membrane bound organelles • Most of multicellular life fits into this category. • However some unicellular life as well • Amoebas, algae, etc
The Plasma Membrane • The flexible boundary between the cell and its environment • Responsible for letting things in and out of the cell and maintaining homeostasis in the cell.
The Plasma Membrane Transport Proteins: specialized proteins that move molecules into and out of the cell • Has Selective Permeability- • The means it allows some molecules to pass through while others or kept out
The Plasma Membrane • The plasma membrane is composed primarily of a phospholipid bilayer • Phospholipids have a polar head (hydrophilic) and a nonpolar (hydrophobic) tail. • Why?
The Plasma Membrane The Fluid Mosaic Model
The Cell Wall • The cell wall: is a rigid structure that is located outside of the plasma membrane that provides additional support and protection. • Found in Plant cells not Animal cells • Also in some bacteria, fungi and protists.
Organelles • Are specialized subunits within a cell that have specific functions • Mini Organs is another way to think about it. • Remember Organelles are only in Eukaryotes • Membrane bound
Organelles Considered the “CONTROL CENTER” of the cell. Site where DNA (genetic information) is stored as Chromatin Nucleus
Organelles Ribosomes are made here • Nucleolus • non-membrane bound structure composed of proteins and nucleic acids found within the nucleus
Ribosomes • Ribosomes • Sites of Protein Synthesis • Not bound, can freely move to different parts of the cell. Found in both eukaryotic and prokaryotic cells
Cytoplasm • Cytoplasm • The clear gelatinous fluid inside a cell • Contains nutrients that allow for cell to grow and develop
Organelles • Endoplasmic Reticulum (rough) • Site of cellular chemical reactions • Help finish protein synthesis • Highly folded • Allows for lots of work in a little space • E.R. (smooth) • Involved in lipid production and storage of lipids
Organelles • Golgi Apparatus (complex): • Protein Post Office of a cell • Packages proteins into vesicles to be sent to appropriate destinations in the cell
Organelles • Vacuole • Membrane-bound compartments used for storage of materials • Lysosome • The garbage disposal of a cell • Uses digestive enzymes to get rid of viruses, bacteria, and old parts of the cell.
Organelles • Mitochondria • The power plants of cells • Transform energy for cell use in the form of ATP.
Chloroplast Capture energy from sunlight and convert it into chemical energy (ATP) in a process called photosynthesis Primarily in Plants Has green chlorophyll (a pigment that captures sunlight)
Cytoskeleton • Is the network of protein filaments that help a cell maintain its shape • Can also aid in cell movement • Microtubules, microfilaments and centrioles are part of the cytoskeleton