Chromosomal Abnormality: 2N-N Condition

Correct Answer: Monoploidy

From the notes: 2N − N = Monoploidy (also called Haploidy) — loss of one complete set of chromosomes.

Euploidy Types (from notes)

• 2N − N → Monoploidy / Haploidy ✔ (one set of chromosomes)
• 2N + N → Triploidy (three sets)
• 2N + 2N → Tetraploidy (four sets)

Distinction: Euploidy vs. Aneuploidy

• Euploidy: Change in the number of complete chromosome SETS (e.g., 2N→N, 2N→3N)
• Aneuploidy: Change in the number of individual chromosomes within a set (e.g., 2N−1, 2N+1)

Both are types of Heteroploidy

Heteroploidy → Euploidy + Aneuploidy. Both are types of chromosomal mutation.