Low-mass main sequence stars also have convective region, but in this case it is their surface layers that are convective, like the Sun’s photosphere. The Sun has a shallow convective region, but for stars with lower masses, the depth of the surface convective zone increases with decreasing mass until, for the main sequence stars of lowest mass, it extends all the way to the core of the star. Figure 19-8 shows the internal structure for main sequence stars of several masses.