Which of the following is true about conidiophores of Penicillium?

The correct option is multicellular and branched.

Penicillium is a genus of saprophytic fungi widely known for its brush-like appearance and its role in producing the antibiotic penicillin. During asexual reproduction, it produces specialized spore-bearing structures known as conidiophores.
Let us break down the key characteristics of these conidiophores step-by-step:

1. Multicellular Nature:
The vegetative body (mycelium) of Penicillium consists of septate hyphae. Similarly, the conidiophores that grow vertically from these hyphae contain septa (cross-walls) dividing them into multiple cells, making them multicellular structures.

2. Branched Structure:
Unlike some other fungi where conidiophores are simple and unbranched, the conidiophores of Penicillium branch near their apex. The main axis of the conidiophore divides to form primary branches called rami. These rami further branch into metulae, which bear flask-shaped cells called phialides (or sterigmata) from which chains of conidia (spores) are produced. This extensive branching gives the conidiophore its characteristic brush-like look (penicillus).

Thus, the conidiophores of Penicillium are multicellular and branched.