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3Discovering CellsAll living organisms are composed of cells, from just one to many trillions, whose details usually are visible only through a microscope
4An Overview of CellsKey concept: Cells are the basic units of structure and function in living things.Examples of function: obtaining oxygen, getting rid of waste, obtaining food, growing, and more…Cells function similarly in all organisms, they carry out the basic processes of life similarlyCells are so small they aremeasured in micrometersOne square centimeter ofSkin is more than 100,000 cellsCells are visible only throughmicroscope
6First Observations of Cells 1590ish invention of the microscopeKey concept: The invention of the microscope made it possible for people to discover and learn about cells.Robert Hookeone of first people to observe cellsbuilt his own microscope- one of the best of his timeobserved cork which looked like small rectangular rooms they called cells
7First Observations of Cells Anton van LeeuwenhookDutch businessmanBuilt simple microscopes in his spare timeLooked at drops of lake water, scrapings from teeth and gums, water from rain guttersAnimalcules- means “little animals,” small organisms that moved that he found in things like lake water
8Development of the Cell Theory Schleiden- all plants are made of cellsSchwann- all animals are made of cellsVirchow- new cells are formed only from cells that already existUntil these men’s time people believed that cells can come from non-living matter
9Cell TheoryAn explanation of the relationship between cells and living thingsAll living things are made of cells.Cells are the basic units of structure and functionAll cells are produced from other cells
11Microscopes Magnification: the ability to make things larger Light MicroscopeMagnification: the ability to make things largerThe light is bent in a light microscope in order to make the specimen larger (using a concave lens)Resolution: the ability to clearly distinguish the individual parts of a specimen
12Microscopes Continued Allows you to see a three dimensional specimenElectron MicroscopeElectron microscopes use a beam of electrons instead of light to produced a high magnified imageElectron is a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids
13MicroscopesMicroscopes allow us to see things we cannot see with the naked eye.
14Unicellular and Multicellular Unicellular- single celledMulticellular- many cellsKey concept: “In multicellular organisms, cells are often organized into tissues, organs, and organ systems.Tissue- a group of singular cells that work togetherOrgans- is made up of different kinds of tissueOrgan system- a group of organs that work together to perform a major function in the body
21CELL WALLProkaryotic cells (bacteria )and plant cells both have a rigid cell wall made up of polysaccharides. The cell wall provides and maintains the shape of these cells and serves as a protective barrier.Can be also found in fungi cells.
22Cell MembraneBoundary between the inside of the cell and its surroundings.The cell membrane controls the movement of nutrients, water, salts, and other substances into the cell and movement of waste out of the cell.The membrane keeps out harmful bacteria, viruses, and other things that could damage the cell.
23Boundaries List five boundaries that you can see around you. For each one, tell what marks the boundary.List what is kept in and what is kept out by the boundary.Example – A fence marks the boundary of the yard.The fence keeps pet dog and young children in.It keeps strange dogs and bicyclists outRead “Heads Out– Tails In”
24CytoplasmThis is a gel-like substance that fills the cell and surround the organelles.It would be in comparison to our environment (air, land, water)
25Organelles Small structures inside the cell membrane. Each organelle has a particular job to do to keep the cell working properly.The organelles are found in the cytoplasm that fills the cell.
26What do all living things need to stay alive? All living things need nutrients, water, and air.All living things need a suitable place to live.
27What are the characteristics of all living things? Respond to their environment, inside and out.Organized to carry out life functions.Grow and develop.Energy.Reproduce.
28What do you think a single cell needs to do in order to stay alive? Read “The Cell as a City”
29Nucleus 1. Stores cell hereditary materials, DNA 2. Coordinates the cells activities (Metabolism, growing, protein synthesis, cell division (reproduction))3. Brain of the cell1. Chromosomes/chromatin: codes for the DNA 2. Nucleolus: Membrane-less organism, that manufactures ribosomes.3. Nuclear Envelope: double-layered membrane that envelopes the contents of the nucleus4. Nuclear Pore: regulates passage of molecules between nucleus and cytoplasm.
30Vacuole Water-filled sack that floats in the cytoplasm. Stores waste, water, and other substances such as food
31Mitochondria Provide energy for the cell by breaking down sugar. Known as the power house of the cellIn a city this would be compared to power plantsMitochondria burn fuel to provide our cells with energy. A chemical reaction called cellular respiration takes place in the mitochondria.Humans cannot live without mitochondria!Why?
32Think about It: No organism can survive without energy Think about It: No organism can survive without energy. How do you get and use energy? Draw the concept map below, list some things in the center box that are sources of energy for your body. In the other boxes list ways your body uses energy.Sources OfEnergy
33On a sheet of paper answer the following: Where would you expect to find more mitochondria-in very active cells such as those in your heart and liver, or in less active cells such as those in your earlobes? Explain your answer.
34Take in and use Energy Cellular respiration Mitochondria burn fuel to provide our cells with energy. A chemical reaction called cellular respiration takes place in the mitochondria.C6H12O O CO2 + 6H2O + energyGlucose + oxygen carbon + water + energydioxide
35Plant Cell’s Power House Plant cells like animal cells have mitochondria, but they also have another kind of energy-converting organelle calleda chloroplast..The process that plants use chloroplast is called photosynthesis.Chlorophyll is thechemical in thechloroplasts thatcaptures sunlight.
36Take in and use Energy Photosynthesis The process that plants use chloroplast is called photosynthesis.6CO H2O +light energy C6H12O6 + 6O2Carbon + water + light energy glucose + oxygendioxide
37Endoplasmic reticulum Carries materials around in the cell.Name some things in a city that would be like the endoplasmic reticulum.Sometimes known as smooth endoplasmic reticulum or rough endoplasmic reticulum if ribosome's are attached.
38Ribosome's Ribosomes are the sites of protein synthesis They can be free in the cytoplasm orattached to the surface of ERThey would be like factories producing needed products.Protein helps with growth and repair of a body.
39Golgi Bodies 1. Final sorting and packaging of proteins and Lipids (fats)2. How does it do that:Membrane breaksaway as vesicles.3. It is like a packaging and shipping center. (The UPS men)What does it look like? stacks of membrane-covered sacs that package and move proteins to the outside of the cell. Golgi bodies are the packaging and secreting organelles of the cell.Note: Golgi Bodies are sometimes referred to as Golgi Apparatus.
40Lysosomes Lysosomes are a special type of vesicle that contain digestiveenzymes.They are round structures surrounded by membranes. Lysosomes recycle materials by breaking down worn-out parts of a cell into smaller units. They deliver these materials to the cytoplasm for use in constructing new proteins. If the membrane of a lysosome breaks, the enzymes released may also destroy the cell itself, giving lysosomes the name "suicide bag".Lysosomes would be like waste processing plants.
41Write a Dialogue:A dialogue is a conversation between at least two people. Choose two of the organelles of a plant or animal cell. Then write a dialogue between them in which they argue about which of them is more important to the cell’s survival.
42You must know all the parts of an animal and plant cell… Click here to practice with an animal and plant cell