Concept:
Aneuploidy is a specialized numerical chromosomal aberration where one or a few individual chromosomes are gained or lost from the regular diploid ($2n$) chromosome complement.
It differs distinctly from euploidy, which involves variations in complete sets of chromosomes ($n, 2n, 3n$, etc.).
Aneuploid variations are critical in plant breeding, genetics, and cytogenetics for chromosome mapping and understanding gene dosage effects.
Specific scientific terms are assigned to denote the exact number and pattern of chromosomes missing or added. Step 1: Analyzing Hypoploidy (Loss of Chromosomes):
- Monosomy ($2n-1$): The loss of a single individual chromosome from a normal diploid genome complement is called monosomy. Thus, A corresponds to II.
- Nullisomy ($2n-2$): The complete loss of an entire pair of homologous chromosomes from a diploid genome is called nullisomy. Thus, C corresponds to IV. Step 2: Analyzing Hyperploidy (Gain of Chromosomes):
- Trisomy ($2n+1$): The addition of an extra individual chromosome to the standard diploid set results in trisomy. Thus, B corresponds to I.
- Tetrasomy ($2n+2$): The addition of an extra pair of homologous chromosomes to the normal diploid complement is termed tetrasomy. Thus, D corresponds to III. Step 3: Synthesizing the Matches:
Aligning the characteristics from List-I with the correct scientific terms in List-II yields:
A $\rightarrow$ II (Monosomy)
B $\rightarrow$ I (Trisomy)
C $\rightarrow$ IV (Nullisomy)
D $\rightarrow$ III (Tetrasomy) Step 4: Final Answer:
This precise combination corresponds to option (B): A-II, B-I, C-IV, D-III.
