The answer to this question is <span>B. The nucleus is surrounded by cell membrane that lets materials in and out.
This cell membrane is called nuclear membrane. Nuclear membrane has small holes that called the nuclear holes that allow materials to come in or out of the nucleus, depending on whether the materials is needed by the nucleus to do its current process.</span>
Radiation is transferred with electromagnetic waves. Radiation gives off heat.
Answer:
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Explanation:
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Answer: Scientist can determine if an object should be classified as living or non-living cells by looking under a microscope with a slide. If the slide has cells in it, it is considered alive and if the cells contain food, water, exposed waste, and environment, it is alive. If the object or slide does not have any cells in it, it is considered non-living because for a cell to be alive, it needs cells in it.</h3>
Looking at the onion root tip under the microscope you can see large, rectangular cells with visible distinct cell walls surrounding it (cells have a more regular shape because of the wall). Inside the cells, you can notice darkly stained nucleus, large vacuoles at the center and sometimes small granules within the cytoplasm. Looking the onion root tip under the microscope is often the way to observe mitosis. Usually, you cannot see organelles such as mitochondria, ribosomes, rough and smooth endoplasmic reticulum, centrioles and Golgi body as they appear translucent and because are too small to be seen under the light microscope (electron microscope required). Also, chloroplasts are not present in an onion cell because it is not a photosynthetic cell.