Question

Gametangial copulation (conjugation) is common in
A. Zygomycetes
B. Ascomycetes
C. Phycomycetes
D. Deuteromycetes

Answer 1

Hint: Gametangial copulation is the direct fusion of the certain fungal gametangia without the differentiation of the gametes.
Sexual reproduction takes place by gametangial copulation and complete fusion takes place by fusion of protoplasts of two gametangia and results in formation of spore.

Complete answer:
A gametangium is an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants.
It is a haploid structure and formation of gametes does not involve meiosis.
Depending upon the type of gametes produced in gametangium, different type are distinguished:
1. Female: It is also commonly known as archegonia. It produces egg cells and is the site of fertilization. In flowering plants, it is replaced by embryo sac inside the ovule.
2. Male: It is also known as antheridia. It produces the sperm cells and releases them for the fertilization. They produce non-motile sperms known as spermatangia.
3. Isogamy: In this gametes look alike which means we cannot distinguish them into male and female gametes. Gametangial copulation is a feature of fertilization in fungi, wherein the whole of the contents of the contacting gametangia fuse together and this happens in two ways -
1. Passage of contents of one gametangium into another through a pore is the characteristic of some holocarpic forms.
2. Direct fusion of the gametangial cells into a single one, which occurs due to the dissolution of the contacting walls and results in a common cell. It is common in class of zygomycetes.

So, the correct option is option A. Zygomycetes.

Note:
The oomycete antheridium is a syncytium with many sperm nuclei and fertilization occurs via fertilization tubes growing from the antheridium and making contact with the egg cells.
Antheridia are common in the gametophytes in "lower" plants such as bryophytes, ferns, cycads and ginkgo. In "higher" plants such as conifers and flowering plants, they are replaced by pollen grains.