The answer in the space provided is trigone. This could be
identified with its appearance of having to show a smooth triangular region in
which is found on the internal part of the urinary bladder. This is likely to
be formed because of the internal urethral orifice and the two ureteric
orifices.
I think the correct answer from the choices listed above is option D. Simple diffusion is the cell transport that allows small molecules to move from an area of higher concentration to an area of lower concentration without energy being <span>required from the cell.</span>
