Bending arrows in Tikz

Question

In Tikz, I would like to bend an arrow like the one between $H_2O$ and $O_2$ in this figure:

I'm able to have a bended line between $H_2O$ and $O_2$, but it's not touching the photophosphorylation node…

How can I do that?

Answer 1

This is most easily done by using the nodes placement, and a to command. You will then be able to achieve the desired result.

\begin{tikzpicture}
  \node at (-2,1) (H2O) {H2O};
  \node[fill=blue] at (2,0) (Photo) {Photophosphorylation};
  \node at (-2,-1) (O2) {O2};
  \draw[->] (H2O.east) to[out=0,in=90] (Photo.west) to[out=-90,in=0] (O2.east);
\end{tikzpicture}

You can then always align them in ingenious ways using matrices or whatever.