Question

During sexual reproduction in Rhizopus, projections from two compatible hyphae are attracted towards each other. These hyphae are called -

• A. Chlamydospores
• B. Azygospores
• C. Progametangia
• D. Zygophores

Hint:

Remember the sequence in {Rhizopus} sexual reproduction: Compatible hyphae produce \textbf{Zygophores} (the branches) \(\rightarrow\) tips swell to form \textbf{Progametangia} \(\rightarrow\) septa form \textbf{Gametangia} \(\rightarrow\) gametangia fuse to form a \textbf{Zygospore}. The question asks about the initial branches.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
The question asks for the name of the specialized hyphae (filaments) in {Rhizopus} (a Zygomycete fungus) that grow towards each other to initiate sexual reproduction.
Step 2: Detailed Explanation:
Let's examine the terms related to sexual reproduction in {Rhizopus}:

Zygophores: These are the specialized, aerial, fertile hyphal branches that arise from compatible mating strains (+ and -). They are chemically attracted and grow towards each other. The name literally means "zygote bearer". This term correctly describes the hyphae mentioned in the question.

Progametangia: When the tips of two zygophores meet, they swell. These swollen tips, before a separating septum is formed, are called progametangia. They are the structures {at the tip} of the hyphae, not the hyphae themselves.

Chlamydospores: These are thick-walled, asexual resting spores formed by the rounding up of a hyphal segment. They are not involved in sexual reproduction.

Azygospores: These are spores that develop parthenogenetically (without fertilization) from a gametangium, but they look like zygospores. They are a type of spore, not a hypha.

Step 3: Final Answer:
The question asks for the name of the hyphae themselves, which are attracted to each other. The correct term for these specialized hyphal projections is zygophores.