The Core is the center of the whole sun.
The suns Core s4.thingpic.com
The radiation zone or radiative zone is a layer of a star's interior where energy is primarily transported toward the exterior by means of radiative diffusion, rather than by convection. Energy travels through the radiation zone in the form of electromagnetic radiation as photons.
The convective zone
Astronomy . the luminous visible surface of the sun, being a shallow layer of strongly ionized gases.
a scarlet, gaseous envelope surrounding the sun outside the photosphere, from which enormous quantities of hydrogen and other gases are erupted.
a white or colored circle or set of concentric circles of light seen around a luminous body, especially around the sun or moon.
a ray of sunlight; sunbeam.