SSC Selection Post 2025 PYQ — Question 5

Correct Answer

Yeast fungus

Explanation

Yeast is a single-celled fungus that does not reproduce through spore formation under normal conditions; instead, its primary and most common method of asexual reproduction is budding.

During budding, a small bulb-like projection or outgrowth, called a bud, develops on the parent yeast cell. The nucleus of the parent cell divides mitotically, and one of the daughter nuclei moves into the growing bud. Eventually, the bud constricts at the base and separates from the parent cell to mature into a new independent yeast individual. Sometimes, a chain of buds can form if new buds start growing before the older ones detach.

The other options listed—Penicillium, Rhizopus (commonly known as bread mold), and other micro fungi—reproduce asexually through spore formation. They develop specialized structures called sporangia or conidiophores that house thousands of tiny, microscopic reproductive units called spores. When these spore cases burst open, the lightweight spores float through the air, and upon landing on a moist, nutrient-rich surface, they germinate to grow into new fungal hyphae.

Key Points

Budding is a form of asexual reproduction where the cellular division is unequal, leaving a distinct birth scar on the parent cell, whereas spore formation involves equal divisions within a protective sac.

Rhizopus utilizes spherical structures called sporangia raised on upright stalks to release non-motile spores into the environment.

Penicillium produces chains of asexually generated spores called conidia at the tips of brush-like branched structures called conidiophores.

Important Questions and Answers

Question: Which type of asexual reproduction is observed in simple multicellular organisms like Hydra, which is highly similar to the reproductive process of single-celled yeast?

Answer: Hydra also reproduces via budding, where a multicellular bud grows on the parent body through repeated cell divisions.

Question: What structural cell wall component provides rigidity and protection to fungal spores, allowing them to survive unfavorable environmental conditions?

Answer: Chitin present in the cell wall provides structural protection to the spores.