Leaves are the plants food factory.
A leaf is a flat, thin plant organ that uses the sun to make its own food. In general leaves are green and use the chemical called chlorophyll to trap energy from the sun. This process is known as Photosynthesis. The energy is used to combine water from the soil and carbon dioxide gas from the air to make sugar. Oxygen is released during this process a process called Respiration. The leaf acts almost like a solar panel for attracting energy from the sun.
Types of Leaves
Most leaves are flat to increase absorption from the sun although this is not always the case. The main flat area is called the blade or lamina. Not all leaves are flat but most are. A simple leaf has an undivided blade. A compound leaf has a fully subdivided blade with is separated by a main or secondary vein.
Leaves come in many different shapes. They may grow in several different arrangements.
What is Eutrophication?
Excessive richness of nutrients in a lake or other body of water, frequently due to run-off from the land, which causes a dense growth of plant life. Eutrophication can have serious effects, like algal blooms that block light from getting into the water and harm the plants and animals that need it. If there’s enough overgrowth of algae, it can prevent oxygen from getting into the water, making it hypoxic and creating a dead zone where no organisms can survive.
How plants are adapted to a wetland?
A wetland is a harsh environment physiologically. Aquatic plants can’t deal with periodic drying and temperatures tend to be more extreme because the water’s shallow terrestrial plants can’t deal with long floods. Stresses include anoxia and wide salinity and water fluctuations. Adaptations to these conditions have an energy cost, either because the organisms cells are working less efficiently (conformers) or because it expends energy to protect cells from external stress (regulators).
Hydrophytes (flood tolerant plants) have adaptations to survive these problems.
Adaptations to Deal with Water and Oxygen
Did you know that plants need oxygen to survive, just like you? The roots of land and water plants use oxygen to make energy and take in water. A plant that is growing in the dirt can pick up oxygen from air pockets in the dirt. But in a wetland, the pockets in the soil are filled with water, so wetland plants have adaptations to help them get oxygen.
Some wetland plants have special air pockets inside their stems called aerenchyma that allow oxygen to flow down into their roots. This word is pronounced air-en-chy-ma, so think of aerenchyma as the air supply for the roots
Most of the plants that grow in soil have roots that are found only at their base. But some wetland plants develop special roots called adventitious roots_ (pronounced ad-ven-tish-es) that sprout off their underwater stems to help the plants take in water, oxygen and other needed things. Think of adventitious roots as roots that like adventure, so they grow out of unusual parts of the plant
Shallow Roots and Elongated Stems
One way to deal with the water of the wetland is to grow out of it. Some wetland plants have long stems that allow them to float on the surface of the water or reach above the water’s surface
For example, cattails are wetland plants with elongated stems. The bases of the cattails are rooted in the underwater marshy soil, while their spiky leaves and hotdog-shaped tops reach above the water surface