Across
- 4. A vascular tissue composed of dead, hollow cells forming tubes that transport water and minerals.Transports water and mineral ions from the roots to the leaves through transpiration pull. It also provides structural support to the plant.
- 5. Mesophyll: A layer of loosely arranged cells with air spaces, located beneath the palisade mesophyll.Facilitates gas exchange (CO₂ in, O₂ out) by allowing gases to diffuse through the leaf. It also has some chloroplasts for photosynthesis.
- 6. Mesophyll:A layer of tightly packed, column-shaped cells found in the upper part of the leaf.Contains numerous chloroplasts to maximize photosynthesis, as it is located near the upper surface of the leaf where light intensity is highest.
- 7. cells and stomata - Stomata are located on the lower side of the leaf and allow carbon dioxide in by diffusion, and water vapour and oxygen out of the leaf by diffusion. Guard cells surround the stomata and can control the opening and closing of the stomata to limit water loss from the plant; when there is a limited water supply, the guard cells cause the stomata to close to prevent water loss. This, however, also reduces the diffusion of carbon dioxide through the stomata for use in photosynthesis, so can cause carbon dioxide to become the limiting factor and reduce the rate of photosynthesis.
- 8. - The cuticle is a clear waxy layer that surrounds the leaf. This provides waterproofing and reduces water loss from the leaf without reducing light absorption.
Down
- 1. - This is where photosynthesis occurs. Chloroplasts contain chlorophyll which allows light energy to be absorbed and converted to chemical energy.
- 2. Ions (NO₃⁻):Nitrate ions are essential nutrients absorbed by plant roots from the soil.They are used to synthesize amino acids, which are the building blocks of proteins. Proteins are vital for plant growth, enzyme production, and cell development. A deficiency causes stunted growth and yellowing of leaves.
- 3. Ions (Mg²⁺): Magnesium ions are essential mineral nutrients absorbed by plants.They are a key component of chlorophyll, the pigment required for photosynthesis. A deficiency results in chlorosis, where leaves turn yellow due to reduced chlorophyll production.
- 6. A vascular tissue made up of living cells responsible for transporting nutrients.Transports sucrose and amino acids from the leaves to other parts of the plant through translocation. This process moves nutrients from sources (e.g., leaves) to sinks (e.g., roots, growing tissues).