Guard cells line the openings of stoma and other organs in plants, opening and closing to moderate the process of respiration. The chief role of guard cells is to prevent an excess loss of water through respiration, allowing the plant to trade oxygen and carbon dioxide without becoming dehydrated.
Guard cells are part of the system that maintains drought resistance in plants. When the plant is filled with moisture, the guard cells become filled with fluid, causing the stoma to open. When the plant loses enough moisture, the stomata wither and draw closed automatically.
In addition, drought-resistant plants often have thick stems in order to store as much moisture as possible and deep root systems to draw moisture from far below the ground.Learn More
As the basic living part of a plant, the plant cell is involved in many physiological and structural activities. They range from synthesis of proteins and energy to maintaining structural integrity and tautness.Full Answer >
Plants are necessary because they are a primary food source and provide the oxygen that is vital to animals' and humans' existence. A majority of the calories that people consume comes from plants, and most meat comes from animals that eat plants. Plants are at the bottom of the food chain, and animals could not survive without them. Plants also release the oxygen that humans and animals breathe.Full Answer >
Plants are green because of a pigment called chlorophyll. Chlorophyll absorbs all colors of visible light except for green, which is reflected. Thus, the reflection of the green part of visible light is what causes plants to look green.Full Answer >
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