Complex sentence: Conidia are 1--2 celled and borne in long, branched chains arising from stalks called conidiophores that are sparingly branched, narrow at the base but widening toward the apex.
Split into simpler sentences: Conidia are 1--2 celled and are produced in long, branched chains arising from stalks called conidiophores. These conidiophores are, sparsely branched, narrow at the base but widening toward the apex.