1 Review What is a cell Explain What three statements make up the cell theory Infer How did the invention of the microscope help the development of the cell theory 2 Review How do microscopes work Apply Concepts What does it mean if a micrograph is false colored CH 7 CELL STRUCTURE AND FUNCTION 7.1 Life is Cellular 1
Robert Hooke 1665 used microscopes Looked in cork Used the word cell. Anton van Leeuwenhoek Early master lens maker Made early microscopes Looked at pond water. 2
Cell Theory 1. The cell is the basic unit of life 2. All living things are made up of at least one cell 3. All cells come from other cells. Compound Light Microscope Light waves pass through small organisms or thin slices of larger ones Up to 1500 times magnification Ours magnify 400 times Used to see bacteria cells, and a few organelles. 3
Stains and Dyes Increases contrast and detail Can see more organelles. Transmission Electron Microscope (TEM) Magnifies up to 1 million times Shows internal structures Specimen has to be dead. 4
Scanning Electron Microscope (SEM) Magnifies up to 1 million times Shows the surface of the specimen Used for cell surfaces, organelle membranes, viruses Specimen may be living. Cell Types Eukaryote Prokaryote 5
Prokaryotes Lack nucleus Lack membrane bound organelles Bacteria. Eukaryotes Have a nucleus Have membrane bound organelles Everything but bacteria. 6
Nucleus Contains the DNA Control center of cell. 7
Cell Membrane Plasma Membrane Controls what goes in and out of cell Protective boundary Semi fluid Similar to skin. 1 Review What is the function of lysosomes Review what is the difference between rough and smooth ER Infer You examine an unknown cell under a microscope and discover that the cell contains chloroplasts. From What type of organism does the cell likely come 2 Review Why is the cell membrane sometimes referred to as a fluid mosaic? What part of the cell membrane acts like a fluid? And what makes it like a mosaic? Explain How do the properties of lipids help explain the structure of a cell membrane Infer Why do you think it s important that cell membranes are selectively permeable? 8
CH 7 CELL STRUCTURE AND FUNCTION 7.2 Cell Structure Organelles Cellular structures that act as if they are specialized organs. 9
Nucleus Contains the DNA Control center of cell. Nucleolus Synthesis and assembly of trna and rrna Contains one or more. 10
Centrioles Major role in mitosis Animal cells. Ribosome Site of protein synthesis Made of RNA May be attached on Endoplasmic Reticulum or free. 11
Golgi Apparatus Modifies Sorts Packages. Golgi Apparatus Modifies Sorts Packages. 12
Golgi Apparatus Modifies Sorts Packages. Chloroplast Site of photosynthesis Plant cells. 13
Mitochondria Site of Cellular Respiration Converts sugar into ATP Makes energy Powerhouse of the cell. Cell Membrane Plasma Membrane Controls what goes in and out of cell Protective boundary Semi fluid Similar to skin. 14
The Properties of Lipids Fatty acid tail are hydrophobic, or water hating Opposite end of the molecule is hydrophilic, or water loving. Selectively permeable Some materials can pass through the membrane and some cannot. 15
1 Review What happens during diffusion Explain Describe the process of osmosis Compare and Contrast What is the difference between diffusion and facilitated diffusion 2 Review How is active transport different from passive transport Explain Describe the two major types of active transport CH 7 CELL STRUCTURE AND FUNCTION 7.3 Cell Transport 16
Concentrations Oil on water Koolaid in water Air freshener in a room Many more examples. 17
Passive Transport Goes from High concentration to Low Concentration Follows concentration gradient Simple diffusion Facilitated diffusion Does NOT use energy. Diffusion Movement of molecules from are of high concentration to low concentration. 18
Simple Diffusion 19
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Facilitated Diffusion Molecules use special protein channels to diffuse across the membrane Does NOT use energy Aquaporins Protein Channel for water. Osmosis Diffusion of water across a membrane. 21
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Isotonic Same concentration on both sides Hypotonic Low concentration Hypertonic High concentration. 23
Osmotic Pressure Force of the net movement of water in or out of a cell. 24
Active Transport Goes from LOW concentration to HIGH concentration Goes AGAINST the concentration gradient Requires energy Why would this be used/where? Molecular Transport 25
Bulk Transport Endocytosis Taking material in Phagocytosis Food Pinocytosis Liquid Exocytosis Removal of material 1 Review What is cellular specialization Explain How do cellular junctions and receptors help an organism maintain homeostasis 2 Description Use an area in your life school sports, etc, to construct an analogy that explains why specialization and communication are necessary for you to function well. 26
CH 7 CELL STRUCTURE AND FUNCTION 7.4 Homeostasis and Cells Homeostasis Relatively constant internal physical and chemical conditions To keep constant unicellular organisms grow, respond to the environment, transform energy, and reproduce. 27
Unicellular organisms are most numerous Eukaryotes may also be unicellular. Multicellular Organisms Cells are independent but work together Cells specialize Cells communicate. 28
Levels of Organization Tissue Group of similar cells that performs a particular function. Levels of Organization Organ Groups of tissues that work together. 29
Levels of Organization Organ system Group of organs that work together to perform a specific function. 30