(Question)
Q: Rudolf virchow developed the hypothesis that cells only come from other cells in what year? Read this paragraph and choose the correct option from the provided answers: In 1858, after using microscopes much better than Hooke's first microscope, Rudolf Virchow developed the hypothesis that cells only come from other cells. For example, bacteria, which are single-celled organisms, divide in half (after they grow some) to make new bacteria. In the same way, your body makes new cells by dividing the cells you already have. In all cases, cells only come from cells that have existed before. This idea led to the development of one of the most important theories in biology, the cell theory . Choices: - 1898 - 1868 - 1848 - 1858 A:
(Answer)
1858

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Q: Where are protons and neutrons located? Read this paragraph and choose the correct option from the provided answers: Unlike protons and neutrons, which are located inside the nucleus at the center of the atom, electrons are found outside the nucleus. Because opposite electric charges attract each other, negative electrons are attracted to the positive nucleus. This force of attraction keeps electrons constantly moving through the otherwise empty space around the nucleus. The Figure below is a common way to represent the structure of an atom. It shows the electron as a particle orbiting the nucleus, similar to the way that planets orbit the sun. Choices: - radius - electron shell - epidermis - nucleus A:
(Answer)
nucleus

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Q: Like all tetrapods except birds and mammals, frogs possess a heart with what structure? Read this paragraph and choose the correct option from the provided answers: Adult frogs are characterized by long hind legs, a short body, webbed finger-like parts, and the lack of a tail. They also have a three-chambered heart, as do all tetrapods except birds and mammals. Most frogs live part of the time in water and part of the time on land. They move easily on land by jumping or climbing. To become great jumpers, frogs evolved long hind legs and long ankle bones. They also have a short backbone with only ten vertebrae. Frog and toad skin hangs loosely on the body, and skin texture can be smooth, warty, or folded. Choices: - One Chamber - four chambers - eight chambers - three chambers A:
(Answer)
three chambers