Clothing Construction & Pattern Making

• Chemical Action of Mordants in Natural Dyeing:
• In natural textile dyeing, metallic salts (mordants) fix dyes onto fibers and modify hue intensity:
• Iron (Ferrous sulfate / Copperas): Known as the saddening agent; it reacts with tannins and natural dye chromophores to dull, darken, and sadden all colors, shifting yellows to olive green and reds to deep purple/black.
• Tin (Stannous chloride): Brilliant brightening mordant.
• Alum (Potassium aluminum sulfate): Clear, neutral mordant maintaining bright natural shades.
• Chrome (Potassium dichromate): Imparts rich warm tones.
• Conclusion: Iron (Option 1).

Correct option: (1) Iron

• Preservation Principle of High Salt and Sugar Concentrations:
• Osmotic Dehydration & Water Activity ($a_w$):
• High concentrations of solutes (salt in pickling $\gt 15\%$, sugar in jams/jellies $\gt 65\%$) create a hypertonic extracellular environment.
• Plasmolysis: Osmotic pressure draws cellular water out of contaminating microbial cells through their semi-permeable cell membranes, shrinking the cytoplasm.
• This sharply lowers free water activity ($a_w \lt 0.60 - 0.75$), depriving bacteria, yeasts, and molds of the moisture essential for enzymatic metabolism and vegetative growth.
• Conclusion: reduce the availability of water for the microorganisms to grow (Option 2).

Correct option: (2) reduce the availability of water for the microorganisms to grow

• Match Natural Vegetable Dyes with Plant Part Used:
• Restored Reference Table:

| List-I (Vegetable colouring matter) | List-II (Part of plant used) |
| :--- | :--- |
| (A) Myrobalan (Harda) | (II) Ripe and unripe fruit |
| (B) Indian Madder (Manjistha) | (III) Root |
| (C) Pomegranate (Anar) | (IV) Fruit rind |
| (D) Acacia (Babul) | (I) Bark |

• Botanical Source Matching:
• Myrobalan (Terminalia chebula): Rich in hydrolysable tannins extracted from dried ripe and unripe fruits $\implies$ (A) $\rightarrow$ (II).
• Indian Madder (Rubia cordifolia): Contains alizarin purpurin dyes extracted from deep roots and rhizomes $\implies$ (B) $\rightarrow$ (III).
• Pomegranate (Punica granatum): Bright yellow/khaki dye obtained from the leathery fruit rind $\implies$ (C) $\rightarrow$ (IV).
• Acacia (Acacia nilotica): Catechu and dark brown tannins extracted from tree bark $\implies$ (D) $\rightarrow$ (I).
• Conclusion: (A) - (II), (B) - (III), (C) - (IV), (D) - (I) (Option 2).

Correct option: (2) (A) - (Il), (B) - (Ill), (C) - (IV), (D) - (1)