Module 3.4 - Leaves

Stomata

Small openings on the surface of leaves that allow for gas exchange, primarily oxygen and carbon dioxide, and transpiration.

Transpiration

• movement of water from the inside of the leaves to the atmosphere outside the leaves

• cools the plant, changes osmostic pressure of cells, enables movement of nutrients and water from roots to shoots

Guard cells

regulate the plants water balance

Examples of leaves that store food

lettuce, spinach, cabbage

examples of underground leaves (bulbs) that store food

onion, garlic

examples of plants that store food in the petiole

rhubarb, celery

Flag Leaf (monocots)

• the final leaf to emerge and may be shaped differently from the rest

• bigger, more exposure to the sun, fills the seed with starch

• if it becomes diseased, this can kill the whole plant