we will use a microscope to look at cells in detail.
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instructions
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cells to tissues to organs to systemsOrgans are made of different tissues, and tissues are made of groups of the same cells. For example, muscle cells together make muscle tissue.
Different types of tissues come together to form organs. For example, the heart is an organ made up of muscle tissue, blood tissue, and nerve tissue. An organ has an important job that keeps the living thing alive. Like animals, plants also have organs. Common plant organs are leaves, stems and roots. A set of organs working together is called an organ system. The heart is part of the circulatory system. Food is broken down in the digestive system. The lungs are part of the breathing (or respiratory) system. The brain is part of the nervous system which carries signals around our bodies. Kidneys are part of the excretory system.An organism is a completely self-sufficient lifeform. You are an organism. All of your cells, tissues, organs and organ systems come together to keep you alive |
Cell theoryToday scientists have developed what we call the Cell Theory. This theory states the following:
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Plant and animal kingdomsThere are many millions of living things on Earth. Scientists don't even know how many as new species are discovered every day!
There are so many organisms that scientists use a classification system so that they can be clear which organisms are which. This also means that scientists can communicate their results across the world and still be understood. |
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