Given the following commutative diagram of exact sequences
$ \begin{array} & & 0 & 0 & 0 &\\ & \downarrow & \downarrow & \downarrow &\\ 0 \rightarrow & A \stackrel{u}\rightarrow & B \stackrel{v}\rightarrow & C \rightarrow & 0\\ & \downarrow f & \downarrow g & \downarrow h &\\ 0 \rightarrow & A_1 \stackrel{u_1}\rightarrow & B_1 \stackrel{v_1}\rightarrow & C_1 & \\ & \downarrow & \downarrow g_1 & \downarrow h_1 &\\ & 0 \rightarrow & B_2 \stackrel{v_2}\rightarrow & C_2 \rightarrow & 0\\ \end{array} $
can I conclude that also $B_1\rightarrow C_1$ is surjective??