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By Kyle, Sam, and Syed Cells
What are cells? Cells are microscopic building blocks in all living organisms. They are the basic unit of all living things. They are constantly dying and multiplying in our body. 3 billion die every minute and the same amount split to replace them. They are essential to life. Imagine the world, it has approximately 7 billion people living on it. We might never know the exact number of cells in the human body but scientist have thought the answer is about 50 trillion. Now think of all those people and multiply those cells by the number of humans on earth. That’s not even including the animals. It is a gigantic number. Now think of an amoeba, a one celled organism that wanders around with little or no purpose whatsoever. Now think of a human, a complicated animal that can taste, feel, hear, see, and smell. They may seem unalike but both are made of cells.
Why are they so small? Cells need food, water, and must get rid of waste. This is done by the process of diffusion. Only certain materials can move through the cell membrane. They enter, travel to the center of the cell, then are moved to an area of lower concentration from the area of higher concentration. The wastes than undergo the same process again, travelling out of the cell. If cells were bigger, this process would take too long and they would require to much food and water to be sustainable for long. In effect, they would also produce too much waste.
Cell Theory Everything alive is composed of anywhere from at least one to trillions of cells. They are also the building blocks of life. The cell theory was initially developed by the combined observations of Robert Hooke, Anton van Leeuwenhoek, Theodor Schwann, Matthias Jakob Schleiden, Rudolf Virchow, and others.
Life Most scientists agree that all living organisms have 5 important things that they all share. • 1. Requirement for energy • 2. Reproduction • 3. Production of waste • 4. They grow • 5 They respond and adapt to their environment Two of the categories of living things are plants and animals. Examples of plants are trees, shrubs, vines, and ferns. Animal examples are dolphins, ferrets, elephants, and cats.
Microscopes The first ever microscope created was made by Zacharious Jansen but there was another one made based on his idea. The creator of that microscope was Anton Van Leeuwenhoek. The types of microscopes made today were similar to Anton’s. The compound light microscope can magnify up to 2000x but the electron microscope can magnify up to 2000000x. Of course the electron microscopes more expensive.
Cell Structures In cells, the structures in general are called organelles. In a plant cell there is cell walls for support. Animal cells don’t need these as they gain their support from our skeletons. They also have chloroplasts for photosynthesis. Cells semi-permeable cell membrane is near the outside for entrance of nutrients and exit of wastes. Inside, there are the vacuole, the nucleus, the nucleolus, the nuclear membrane, mitochondrion, cytoplasm, amyloplast, centrosome, rough ER, smooth ER, ribosomes, and the goigi body.
Similarities and Differences All living organisms have one thing in common- cells. It doesn’t matter what size or shape they're all made up of cells. They also produce waste, reproduce, exchange gases and they respond and adapt to their environment. But many living organisms have different structures and functions. Elephants have trunks to drink and bathe themselves while moles have claws to dig. Monkey have thumbs to grasp things while birds have wings to fly. All living organisms have things in common and they also have many different things.
References http://dvr-education.blogspot.ca/2012/07/robert-hooke-father-of-microscopy.html http://www.findingdulcinea.com/features/profiles/v/anton-van-leeuwenhoek.html http://chemistry.about.com/od/aprilinscience/tp/april5history.htm http://www.merke.ch/biografien/biologen_en/schwann.php http://www.petitmusee.org/pages/ameba_jpg.htm http://www.jeol.com/PRODUCTS/ElectronOptics/TransmissionElectronMicroscopesTEM/300kV/JEM3100F/tabid/128/Default.aspx http:/www.enchantedlearning.com/subjects/plants/cell/ Mr. Shackleford’s Unit 2 Cells and Systems Powerpoint Science Focus 8 Textbook http://www.enchantedlearning.com/subjects/plants/cell/ http://mrshacksclass.edublogs.org/ http://www.wikipedia.org/ http://www.google.ca/ https://podcast.ad.edenpr.org/groups/ephsenrichedbiology2011/weblog/e0258/ http://www.bitrebels.com/technology/geek-alert-brain-cells-under-a-microscope/ http://www.greatplay.net/uselessia/articles/theanswer.html http://torontotenniscity.com/personal-message-from-allan-maihttp://playfulove.com/research.html http://gardenoflearningsc.blogspot.ca/2011/11/thumbs-up-award.html