Question

The total number of ascospores in Penicillium is:
a. 8
b. 16
c. 4
d. 2

Answer 1

Hint: Fungi are multicellular eukaryotic organisms having a separate kingdom Fungi. Penicillium is a genus of the fungi ascomycetous. It plays an important role in the natural environment and for the production of food and drugs.

Complete answer:
Penicillium is one of the large genus that can be found easily everywhere, especially in soil. Some of the species of the genus Penicillium produce penicillin, a highly beneficial molecule used as an antibiotic to kill some kinds of bacteria or to cease their growth.

The name Penicillium is derived from a latin word, meaning “painter’s brush”, because the chains of conidia look like a brush.

Penicillium can be identified as a structure having dense brush-like spores bearing organs called penicillin. Thallus has branched multinucleated hyphae where the paired cells are divided through a septum. At the edge of each branch, conidiophores are present along with small units called conidia, which are useful in the process of reproduction. The spores, known as conidia, are produced in the form of a chain at the top of phialides. The youngest spore remains at the bottom of the chain and the matured one at the top. The spores are green in colour.

During sexual reproduction, archegonium fuses with antheridium producing ascospores.
Most of the species of Penicillium reproduce sexually with the help of asci and ascospores. Single diploid ascus when undergoes meiotic division, it gives rise to four haploid nuclei. This step also signifies that during meiotic division, the single diploid cell that has DNA is duplicated to form four sets of it. All four nuclei will have one complete set of chromosomes. Then these nuclei undergo mitotic division to produce 4 parts of spores that are called ascospores. Eight unicellular ascospores are present in a single ascus. An Ascospore is only produced if the conditions are favourable.

Hence, the correct answer is option (A).

Note: Penicillium grows preferably in cold climates in soil. They are commonly known as molds. Some species of penicillium are toxic and if present in food, can make it inedible or very harmful to eat. Thus it is advised to not eat food that shows mould development in it. They are found mostly in stored food where a cold and moist surface is present. Some Penicillium species are known to cause machinery damage as well.
But some species are useful for humans such as the one producing penicillin used to make antibiotics. Other species are used in making cheese and are safe to consume.