Yard : fence : : cell : nucleus cytoplasm membrane mitochondria

The correct answer is membrane. Just like the fence protects the yard so does a membrane protect the cell. It prevents things from getting in or out unless passageways are created. The things in the yard would be the mitochondria and other organelles, while the air in the yard and the ground where all things are found would be the cytoplasm. The membrane protects what's in just like a fence protects those in the yard.

The scientific method is a series of steps followed by scientific investigators to answer specific questions about the natural world. it involves making observations, formulating a hypothesis, and conducting scientific experiments.the steps of the scientific method are •observation-the first step of the scientific method involves making an observation about something that interests you•question-once you've made your observation, you must formulate a question about what you have observed. •hypothesis-once you've made your observation, you must formulate a question about what you have observed. •experiment-once you've developed a hypothesis, you must design and conduct an experiment that will test it.•results-the results are where you report what happened in the experiment. •conclusion-the final step of the scientific method is developing a conclusion.i hope that this you : )