Of course they also connect the roots to the leaves, transporting absorbed water and minerals from the roots to the rest of the plant, and transporting sugars from the leaves (the site of photosynthesis) to desired locations throughout the plant. Their main function is to provide support to the plant, holding leaves, flowers and buds. Stems are a part of the shoot system of a plant. The text below was adapted from OpenStax Biology 30.2 Epiphytic roots enable a plant to grow on another plant.Some tap roots, such as carrots, turnips, and beets, are adapted for sugar/starch storage.Aerial roots and prop roots are two forms of above-ground roots that provide additional support to anchor the plant.Root structures are evolutionarily adapted for specific purposes: Image credit: OpenStax Biology, modification of work by Austen Squarepants/Flickr) (a) Tap root systems have a main root that grows down, while (b) fibrous root systems consist of many small roots. Fibrous roots are typical of monocots such as grasses. Fibrous root systems can help prevent soil erosion. Fibrous root systems are located closer to the surface and have a dense network of roots.Tap roots are typical of dicots such as dandelions. Tap roots penetrate deep into the soil and are advantageous for plants growing in dry soils. Tap root systems have a main root that grows down vertically, and from which many smaller lateral roots arise.Root systems are mainly of two types (shown below): Some plants, however, also have adventitious roots, which emerge above the ground from the shoot. Some roots are modified to absorb moisture and exchange gases. The roots of seed plants have three major functions: anchoring the plant to the soil, absorbing water and minerals and transporting them upwards, and storing the products of photosynthesis. The text below was adapted from OpenStax Biology 30.3 We’ll look at each of these levels of plant organization in turn, and conclude with a discussion of how embryogenesis leads to development of a mature plant: The Root System The root system anchors the plant while absorbing water and minerals from the soil. The shoot system of a plant consists of leaves, stems, flowers, and fruits. The organ systems of a typical plant are illustrated below. The root system, which supports the plants and absorbs water and minerals, is usually underground. The shoot system generally grows above ground, where it absorbs the light needed for photosynthesis. The shoot system consists stems, leaves, and the reproductive parts of the plant (flowers and fruits). Vascular plants have two distinct organ systems: a shoot system, and a root system. The text below was adapted from OpenStax Biology 30.1 We will go through each of the organs, tissues, and cell types in greater detail below. Different cell types comprise each tissue type, and the structure of each cell type influences the function of the tissue it comprises. Each organ (roots, stems, and leaves) include all three tissue types (ground, vascular, and dermal). The stems and leaves together make up the shoot system. The relationships between plant organs, tissues, and cell types are illustrated below. Like animals, plants are multicellular eukaryotes whose bodies are composed of organs, tissues, and cells with highly specialized functions.
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