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  1. Cell membrane ; Function: Its structure is permeable to some substances but not to others. It therefore controls the movement of substances in and out of the cell.

    • Plant and Animal Cells

      Cell structure - AQA Plant and animal cells. Organisms are...

    • Video

      How are cells structured? Learn about the size and function...

    • Epidermis
    • Palisade Mesophyll
    • Spongy Mesophyll
    • Vascular Bundle

    An epidermal leaf cell is any cell which protects the outside of the leaf. These cells are often short and flattened, much like a square pancake. They form a protective layer over the leaf. They often produce waxy substances which protect the leaf from drying out or being attacked by insects. A leaf cell in the epidermis often lacks chloroplasts, t...

    The palisade mesophyll consists of a type of leaf cell specifically designed to carry out photosynthesis. These cells are absolutely packed with chlorophyll, and simply work their hardest to pump out as much sugar as they can. This sugar they release into the intracellular space, where it works its way to the next type of leaf cell.

    Spongy mesophyll is exactly what it sounds like: a loose matrix of structural mesophyll cells. These cells are not neatly packed into rows like the palisade cells. Rather, they form networks around bundles of vascular cells, and transport materials to and from the bundles. Like palisade mesophyll leaf cells, they can photosynthesize, but they carry...

    The last type of leaf cell is not specific to the leaf, as it travels the entire length of the plant. The cells around the xylem and phloem together make the vascular bundle. These highly specialized cells allow water and minerals to flow up from the roots, while transporting the products of photosynthesis to the entire plant. Like the arteries and...

    • Cell Wall. It is the outermost, protective layer of a plant cell having a thickness of 20-80 nm. Cell walls are made up of carbohydrates such as cellulose, hemicellulose, and pectin and a complex organic polymer called lignin.
    • Plastids. They are double membrane-bound organelles that have their own genetic material. Plastids are mainly of three types: a) Chloroplasts: Found in the green parts of a plant and algae that contain the photosynthetic pigment, chlorophyll.
    • Central Vacuole. It is the large vesicle that make up almost 30 to 80% of the total plant cell volume. The central vacuole is often the largest organelle in the cell that is filled with fluid, ions, enzymes, and other molecules.
    • Cell Membrane or Plasma Membrane. It is a thin, biological membrane having a thickness of 7.5-10 nm that separates the interior of the cell from the outside environment.
  2. Oct 31, 2023 · Similar to the stem, the leaf contains vascular bundles composed of xylem and phloem. The xylem consists of tracheids and vessels, which transport water and minerals to the leaves. The phloem transports the photosynthetic products from the leaf to the other parts of the plant.

  3. Both prokaryotic and eukaryotic cells have a plasma membrane (Figure 3.1.2.2 3.1.2. 2), a phospholipid bilayer with embedded proteins that separates the internal contents of the cell from its surrounding environment. A phospholipid is a lipid molecule with two fatty acid chains and a phosphate-containing group.

  4. Feb 17, 2023 · Leaves are complex organs consisting of several layers serving various essential functions. They are the site of photosynthesis in plants, producing food. For cellular functions like photosynthesis and respiration, leaves require several cells and tissues to work in coordination.

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  6. A chemical process used by plants to make glucose and oxygen from carbon dioxide and water, using light energy. Oxygen is produced as a by-product of photosynthesis. Algae...