Q2 Study Note #3 Shoot System (Leaves).pdf

Study Note #3: Shoot System (Leaves) Learning Competencies: The learners should be able to: 1. Observe the root and shoot system in plants and describe why they are important (S4LT-2) 2. LEAVES Leaves are an essential part of a pl...

Study Note #3: Shoot System (Leaves) Learning Competencies: The learners should be able to: 1. Observe the root and shoot system in plants and describe why they are important (S4LT-2) 2. LEAVES Leaves are an essential part of a plant. They are usually flat and green, and they grow from the stem or branches. The primary role of leaves is to produce food for the plant through a process called photosynthesis. NOTE: Leaves have various shapes and sizes. Parts of a Leaf Leaf Blade Main vein Petiole Side vein Leaf Blade (Lamina) The leaf blade, also known as the lamina, is the broad, flat part of the leaf. It’s the main area where photosynthesis happens because it captures sunlight. Main Vein (Midrib) The main vein, also known as the midrib, is the central, prominent vein that runs through the middle of the leaf blade. It provides support to the leaf and is the main pathway for transporting water, nutrients, and food between the stem and the leaf.  Side Veins Side veins are the smaller veins branching out from the main vein across the leaf blade. They form a network that spreads throughout the leaf, reaching all parts of the blade. Petiole The petiole is the stalk that connects the leaf blade to the stem of the plant. It’s like a small bridge that holds the leaf out from the stem, positioning it to get the best light exposure. Functions of a Leaves Photosynthesis Leaves act like the plant’s kitchen. They take in sunlight, carbon dioxide from the air, and water from the soil to make food (sugar) for the plant. This process is called photosynthesis. The green color in leaves comes from a substance called chlorophyll, which helps capture sunlight. Gas Exchange Leaves have tiny openings on their surface called stomata. These stomata allow the plant to take in carbon dioxide and release oxygen, which is important for the plant and for the environment. Transpiration Leaves help control the amount of water in a plant. They release excess water into the air through the stomata in a process called transpiration, which also helps keep the plant cool.