Question - What are the different layers of a leaf?

Answered by: Jeffrey Patterson  |  Category: General  |  Last Updated: 18-06-2022  |  Views: 1184  |  Total Questions: 14

A cross section through the blade of a typical dicot leaf reveals 4 distinct tissue layers. Upper epidermis. This is a single layer of cells containing few or no chloroplasts. Palisade layer. Spongy layer. Lower epidermis. The basic angiosperm leaf is composed of a leaf base, two stipules, a petiole, and a blade (lamina). … The main function of a leaf is to produce food for the plant by photosynthesis. Chlorophyll, the substance that gives plants their characteristic green colour, absorbs light energy. A layer of cells just below the upper surface of most leaves, consisting of cylindrical cells that contain many chloroplasts and stand at right angles to the leaf surface. It is the principal region of the leaf in which photosynthesis is carried out and lies above or to the outside of the spongy parenchyma. All leaves have the same basic structure - a midrib, an edge, veins and a petiole. The main function of a leaf is to carry out photosynthesis, which provides the plant with the food it needs to survive. Plants provide food for all life on the planet.

Leaves are classified as either alternate, spiral, opposite, or whorled. Plants that have only one leaf per node have leaves that are said to be either alternate or spiral. Alternate leaves alternate on each side of the stem in a flat plane, and spiral leaves are arranged in a spiral along the stem.

Its main functions are photosynthesis and gas exchange. A leaf is often flat, so it absorbs the most light, and thin, so that the sunlight can get to the chloroplasts in the cells. Most leaves have stomata, which open and close. They regulate carbon dioxide, oxygen, and water vapour exchange with the atmosphere.

A group of organs work together to form an organ system. Organs exist in all higher biological organisms, they are not restricted to animals, but can also be identified in plants. For example, the leaf is an organ in a plant, as is the root, stem, flowers and fruits.

Plants typically have six basic parts: roots, stems, leaves, flowers, fruits, and seeds.

Initial leaf formation begins immediately behind the top meristem (1) with periclinal divisions (with the division plane parallel to the surface; red in figure 2) in the subepidermal celllayers and soon later in the epidermis. A leaf stalk is absent. The opposite side develops into the leaf blade.

The leaves perform three main functions such as manufacture of food, interchange of gases between the atmosphere and the plant body and evaporation of water.

The lamina also contains vascular tissue that deliver water and nutrients and carry away the products of photosynthesis. The primary function of the lamina is photosynthesis. This includes both light capture and the dark reactions.

Leaf. While GREEN leaves depict hope, renewal, and revival, dead leaves represent decay and sadness. In general, leaves are symbolic of fertility and growth, and in the Chinese tradition the leaves of the Cosmic Tree represent all of the beings in the universe.

The first root that comes from a plant is called the radicle. A root's four major functions are 1) absorption of water and inorganic nutrients, 2) anchoring of the plant body to the ground, and supporting it, 3) storage of food and nutrients, 4) trans locating water and minerals to the stem.

The primary purpose of a flower is reproduction. Since the flowers are the reproductive organs of plant, they mediate the joining of the sperm, contained within pollen, to the ovules — contained in the ovary. Pollination is the movement of pollen from the anthers to the stigma.

Venation : The arrangement of veins and veinlets in the lamina of a leaf is called venation. The veins are not only the conducting channels for water, minerals and organic food/, they also provide firmness to the lamina and keep it expanded.

Most leaves have a stem (or petiole) that attaches the leaf to the rest of the plant. The petiole sometimes extends into the leaf and divides the leaf into two equal halves, and when it does it's called the midrib. The thin “leafy” portion on either side of the midrib is called the blade.

Within each leaf, the vascular tissue forms veins. The arrangement of veins in a leaf is called the venation pattern. Monocots and dicots differ in their patterns of venation. Monocots have parallel venation in which the veins run in straight lines across the length of the leaf without converging.