Final answer:
Mutations in porins can be heritable if they occur in germ cells. In the context of fungi, if a mutation prevents the production of a minus mating type, the fungus can still reproduce asexually, ensuring its survival.
Step-by-step explanation:
When considering if the production of mutated porins is heritable, one must determine whether the mutation affects germ cells or somatic cells. Mutations in germ cells (sperm or egg) are heritable and can be passed on to offspring, whereas mutations in somatic cells (like skin or other body cells) cannot be passed on to the next generation. Porins are proteins that can be part of a bacterium or fungus, for instance, and in the given context of fungi, if a mutation occurs so that a fungus is no longer able to produce a minus mating type, the fungus would still be able to reproduce, but only asexually. Sexual reproduction in certain fungi requires both the plus and minus mating types to fuse and produce offspring. However, many fungi also have the capability to reproduce asexually, thus ensuring their survival in the absence of one mating type.