A nucleus is primarily responsible for directing all processes and reactions in a plant cell. <span>The function of the </span>nucleus<span> in the </span>plant cell<span> is to store the </span>plant's<span> DNA and control the activity of the </span>cell <span>through protein synthesis. The </span>nucleus<span> is enclosed by the </span>nuclear membrane<span>, which has pores for the passage of RNA and proteins. </span>