Mitotic stages and chromosome morphology:
In Anaphase, the centromere connecting sister chromatids synchronously cleaves/divides, and the spindle fibers contract to pull sister chromatids toward opposite spindle poles.
Because the centromere leads the movement while the chromosome arms trail behind, chromosomes assume characteristic shapes depending on centromere position:

• Metacentric chromosomes: appear distinctly 'V' shaped (two equal arms).
• Sub-metacentric: 'L' shaped.
• Acrocentric: 'J' shaped.
• Telocentric: 'I' shaped.

Modified dihybrid phenotypic ratios in epistasis:
(A) Dominant Epistasis -> (II) 12:3:1: When a dominant allele of one gene masks the expression of both alleles of another gene (e.g., fruit color in summer squash).
(B) Inhibitory Gene Action -> (I) 13:3: When a dominant inhibitor gene suppresses the expression of a dominant allele of another gene (e.g., feather color in fowl, grain color in rice).
(C) Duplicate Epistasis (Duplicate Dominant) -> (III) 15:1: When either of two independent dominant genes produces the phenotype (e.g., shepherd's purse fruit shape, awned vs awnless in rice).
(D) Complementary Gene Action (Duplicate Recessive) -> (IV) 9:7: When dominant alleles of both genes must be present together to produce the phenotype (e.g., flower color in sweet pea).

Vegetative propagation methods in Mango (Mangifera indica):
Veneer Grafting is the most widely adopted, standardized, and commercially successful vegetative propagation technique for mango in Northern India.
It offers high success rates (80-90%), can be performed on 1-year-old rootstocks during March-April and July-August, allows detached scion wood to be stored and transported, and yields vigorous saplings.
Inching (approach grafting) was the traditional method in North India, but veneer grafting largely replaced it due to high efficiency.