Answer:
A nuclear membrane is a double membrane that encloses the cell nucleus. It serves to separate the chromosomes from the rest of the cell. The nuclear membrane includes an array of small holes or pores that permit the passage of certain materials, such as nucleic acids and proteins, between the nucleus and cytoplasm.
The best answer would be "research reasons why species change over long periods of time"
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Answer:
A hydrogen atom is an atom of the chemical element hydrogen.Carbon is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds.
In chemistry, an element is a pure substance consisting only of atoms that all have the same numbers of protons in their atomic nuclei.
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