Question

Match List-I with List-II.

List-I	List-II
A. Fusion of protoplasms between gametes	I. Meiosis
B. Fusion of two nuclei	II. Plasmogamy
C. Generation of haploid spores	III. Karyogamy

Choose the correct answer from the options given below :

• A. A-I, B-III, C-II
• B. A-II, B-III, C-I
• C. A-II, B-I, C-III
• D. A-III, B-II, C-I

Hint:

To easily remember the sequential stages of sexual reproduction in fungi, just recall the abbreviation P-K-M: \[ \text{\textbf{P}lasmogamy (Protoplasm)} \rightarrow \text{\textbf{K}aryogamy (Nuclei)} \rightarrow \text{\textbf{M}eiosis (Spores)} \] Breaking down terms etymologically (plasmo = cytoplasm, karyo = nucleus) eliminates any potential confusion!

Answer 1

The Correct Option is B

Concept: In the sexual reproduction cycle of fungi and many lower eukaryotic organisms, the progression toward producing offspring involves a highly coordinated series of cellular and nuclear events. This sequence follows three fundamental steps: the merging of cellular fluids, the subsequent merging of genetic centers, and eventually a reduction division to restore a haploid genome.

Step 1: Analyze Item A ("Fusion of protoplasms between gametes")
The cell contents excluding the nucleus are referred to as the protoplasm or cytoplasm. The word prefix plasmo- relates to the plasma or cell fluid, and -gamy means marriage or union. Therefore, the physical fusion of motile or non-motile gametic protoplasms without immediate nuclear fusion is defined precisely as

Plasmogamy. This matches A with II.

Step 2: Analyze Item B ("Fusion of two nuclei")
Following plasmogamy, the cell contains two independent nuclei (often creating a dikaryon phase). The Greek word karyon refers to a nut or kernel, which scientifically denotes the cell nucleus. Hence, the fusion of these two haploid nuclei to form a single diploid ($2n$) zygotic nucleus is called

Karyogamy. This matches B with III.

Step 3: Analyze Item C ("Generation of haploid spores")
Once a diploid nucleus is successfully produced via karyogamy, the organism must reduce its chromosome count back to the haploid state ($n$) to complete its life cycle and form reproductive propagation structures. This specialized reduction division is called

Meiosis. The spores resulting from this process are haploid sexual spores. This matches C with I.

Step 4: Compiling the final matches
Combining the findings from the previous steps, we get:

• A $\rightarrow$ II

• B $\rightarrow$ III

• C $\rightarrow$ I
This precise configuration corresponds perfectly to option (2).