How do substances pass between the
inside of the nucleus and the surrounding cell cytoplasm? (A) Through nuclear pores, (B)
through gaps in the nucleus wall, (C) through the nuclear stomata, or (D) via
nuclear transport tissues.
The nucleus is a membrane-bound
organelle which contains the majority of a eukaryotic cell’s genetic material in the
form of DNA. Its function is to protect DNA from
the reactions that occur in the cytoplasm, and it does this using its membrane,
which is called the nuclear envelope. However, some material must pass
between the nucleus and the cytoplasm in order to give the cell essential
instructions. So how does this happen? The nuclear envelope contains small
openings called nuclear pores, which some molecules can pass through. Chromosomes are unable to pass
through the nuclear pores because they’re too large. mRNA molecules, on the other
hand, are much smaller, and therefore they can pass through easily.
Thanks to nuclear pores, mRNA can
pass from the nucleus into the cytoplasm where it can meet a ribosome, and together
they can carry out protein synthesis. We have therefore determined that
the correct answer is (A): substances pass between the inside of the nucleus and the
surrounding cell cytoplasm through nuclear pores.