Answer:
### Collenchyma
**Functions:**
1. **Support:** Collenchyma cells provide structural support to growing parts of the plant, such as young stems and leaves, allowing them to withstand various mechanical stresses.
2. **Flexibility:** These cells are flexible and can elongate, helping the plant to bend without breaking.
3. **Protection:** Collenchyma tissues protect the plant from physical damage.
### Sclerenchyma
**Functions:**
1. **Strength and Rigidity:** Sclerenchyma cells are thick-walled and lignified, providing rigidity and strength to mature plant parts, such as stems, bark, and seed coats.
2. **Support:** They offer structural support, especially in parts of the plant that are no longer growing.
3. **Protection:** Sclerenchyma cells help protect seeds and other plant parts from predation and mechanical damage.
### Parenchyma
**Functions:**
1. **Photosynthesis:** Parenchyma cells in the leaves (mesophyll cells) contain chloroplasts and are involved in photosynthesis.
2. **Storage:** They store nutrients, water, and other substances in roots, stems, and leaves.
3. **Healing and Regeneration:** Parenchyma cells can dedifferentiate and divide, aiding in the healing of wounds and regeneration of plant tissues.
4. **Transport:** They help in the transport of nutrients and water through diffusion and active transport within the plant.
