The poky phenotype (slow growth) in the bread mold Neurospora crassa
is a mutation in cytochrome proteins that disrupts aerobic respiration. This trait is
"maternally" inherited, suggesting
cytoplasmic transmission via mitochondria.
Neurospora mating involves fusion of conidia
of opposite mating types.
One of the cells contributes most of the cytoplasm and may be considered the "maternal" parent.