The structures for gaseous exchange in breathing roots are

1. Analyze the question The question asks which structures allow gaseous exchange in breathing roots (pneumatophores). These are specialised roots found in plants growing in swampy or waterlogged soils, such as mangroves along the Niger Delta coast.

2. Explain the concept Mangrove roots are buried in waterlogged, oxygen-poor mud. To get oxygen, some roots grow upward out of the mud and into the air. These are called pneumatophores, or breathing roots.

Their surface is covered with small pores called lenticels. Lenticels are porous patches in the bark or outer tissue of woody stems and roots. Air enters through them and moves into the spongy internal tissue (aerenchyma), where it reaches the submerged root parts.

3. Check each option

• A. Stomata: These are found mainly on leaves and young green stems, not on roots.
• B. Lenticels: These are pores on woody stems and breathing roots. They allow gaseous exchange. ✔
• C. Cuticle: This is a waxy layer that reduces water loss. It is not a structure for gas exchange.
• D. Mitochondria: These are cell organelles where respiration takes place. They are not exchange structures on the root surface.

4. Answer The correct option is B. lenticels.

5. Exam tip Remember the pairing:

• Leaves → stomata
• Woody stems and breathing roots → lenticels
• Aquatic plants and mangroves → pneumatophores with lenticels

Whenever you see "breathing roots" or "woody stem", think lenticels.