Stem-changing Spanish c>zc verbs in the present subjunctive

In Spanish some verbs ending in -cer/-cir undergo a stem change in the present subjunctive, in a very similar way they do in the present indicative. They will switch the -c for -zc. The difference is that while in the present indicative only the yo form is affected by this stem change, in the present subjunctive all forms keep the stem change.
Have a look at these tables showing both the present indicative and the present subjunctive of conocer (to know/meet):

	CONOCER (present indicative)	CONOCER (present subjunctive)
yo	conozco	conozca
tú	conoces	conozcas
él / ella / usted	conoce	conozca
nosotros / nosotras	conocemos	conozcamos
vosotros / vosotras	conocéis	conozcáis
ellos / ellas/ ustedes	conocen	conozcan