Plant cells are the cells present in green plants, photosynthetic eukaryotes of the kingdom Plantae. Their distinctive features include primary cell walls containing cellulose, hemicelluloses and pectin, the presence of plastids with the capability to perform photosynthesis and store starch, a large vacuole that regulates turgor pressure, the absence of flagella or centrioles, except in the gametes, and a unique method of cell division involving the formation of a cell plate or phragmoplast that separates the new daughter cells.
Xylem is one of the two types of transport tissue in vascular plants, the other being phloem. The basic function of xylem is to transport water from roots to stems and leaves, but it also transports nutrients. The word xylem is derived from the Ancient Greek word ξύλον (xylon), meaning "wood"; the best-known xylem tissue is wood, though it is found throughout a plant. The term was introduced by Carl Nägeli in 1858.
Phloem is the living tissue in vascular plants that transports the soluble organic compounds made during photosynthesis and known as photosynthates, in particular the sugar sucrose, to the rest of the plant. This transport process is called translocation. In trees, the phloem is the innermost layer of the bark, hence the name, derived from the Ancient Greek word φλοιός (phloiós), meaning "bark". The term was introduced by Carl Nägeli in 1858.
Vascular plants, also called tracheophytes or collectively Tracheophyta, form a large group of land plants that have lignified tissues for conducting water and minerals throughout the plant. They also have a specialized non-lignified tissue to conduct products of photosynthesis. Vascular plants include the clubmosses, horsetails, ferns, gymnosperms, and angiosperms. Scientific names for the group include Tracheophyta, Tracheobionta and Equisetopsida sensu lato. Some early land plants had less developed vascular tissue; the term eutracheophyte has been used for all other vascular plants, including all living ones.
Platanaceae, the "plane-tree family", is a family of flowering plants in the order Proteales. The family consists of only a single extant genus Platanus, with eight known species. The plants are tall trees, native to temperate and subtropical regions of the Northern Hemisphere. The hybrid London plane is widely planted in cities worldwide.
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines, and shrubs. Bark refers to all the tissues outside the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner bark, which in older stems is living tissue, includes the innermost layer of the periderm. The outer bark on older stems includes the dead tissue on the surface of the stems, along with parts of the outermost periderm and all the tissues on the outer side of the periderm. The outer bark on trees which lies external to the living periderm is also called the rhytidome.
The Pinaceae, or pine family, are conifer trees or shrubs, including many of the well-known conifers of commercial importance such as cedars, firs, hemlocks, piñons, larches, pines and spruces. The family is included in the order Pinales, formerly known as Coniferales. Pinaceae are supported as monophyletic by their protein-type sieve cell plastids, pattern of proembryogeny, and lack of bioflavonoids. They are the largest extant conifer family in species diversity, with between 220 and 250 species in 11 genera, and the second-largest in geographical range, found in most of the Northern Hemisphere, with the majority of the species in temperate climates, but ranging from subarctic to tropical. The family often forms the dominant component of boreal, coastal, and montane forests. One species, Pinus merkusii, grows just south of the equator in Southeast Asia. Major centres of diversity are found in the mountains of southwest China, Mexico, central Japan, and California.
Bauhinia is a large genus of flowering plants in the subfamily Cercidoideae and tribe Bauhinieae, in the large flowering plant family Fabaceae, with a pantropical distribution. The genus was named after the Bauhin brothers Gaspard and Johann, Swiss-French botanists.
Bauhinia × blakeana, commonly called the Hong Kong orchid tree, is a hybrid leguminous tree of the genus Bauhinia. It has large thick leaves and striking purplish red flowers. The fragrant, orchid-like flowers are usually 10 to 15 centimetres across, and bloom from early November to the end of March. Although now cultivated in many areas, it originated in Hong Kong in 1880 and apparently all of the cultivated trees derive from one cultivated at the Hong Kong Botanical Gardens and widely planted in Hong Kong starting in 1914. It is referred to as bauhinia in non-scientific literature though this is the name of the genus. It is sometimes called the Hong Kong orchid. In Hong Kong, it is most commonly referred to by its Chinese name of 洋紫荊 (yèuhng jígīng).
Lepidodendron is an extinct genus of primitive vascular plants belonging to order Lepidodendrales, part of a group of Lycopodiopsida known as scale trees or arborescent lycophytes, related to quillworts and lycopsids. They were part of the coal forest flora. They sometimes reached heights of 50 metres, and the trunks were often over 1 m (3.3 ft) in diameter. They thrived during the Carboniferous Period. Sometimes erroneously called "giant club mosses", the genus was actually more closely related to modern quillworts than to modern club mosses. Within the form classification system used within paleobotany, Lepidodendron is both used for the whole plant as well as specifically the stems and leaves.
The ground tissue of plants includes all tissues that are neither dermal nor vascular. It can be divided into three types based on the nature of the cell walls.
- Parenchyma cells have thin primary walls and usually remain alive after they become mature. Parenchyma forms the "filler" tissue in the soft parts of plants, and is usually present in cortex, pericycle, pith, and medullary rays in primary stem and root.
- Collenchyma cells have thin primary walls with some areas of secondary thickening. Collenchyma provides extra mechanical and structural support, particularly in regions of new growth.
- Sclerenchyma cells have thick lignified secondary walls and often die when mature. Sclerenchyma provides the main structural support to a plant.
The Hernandiaceae are a family of flowering plants (angiosperms) in the order Laurales. Consisting of five genera with about 58 known species, they are distributed over the world's tropical areas, some of them widely distributed in coastal areas, but they occur from sea level to over 2000 m.
South Asian pickles, also known as Avalehikā, Uppinakaayi, Pachadi, Loncha or Noncha, Achaar, Athāṇu or Athāṇo or Athāna, Khaṭāī or Khaṭāin, Sandhan or Sendhan or Sāṇdhāṇo, Kasundi, or oorugaai is a pickled food made from a variety of vegetables and fruits preserved in brine, vinegar, edible oils, and various South Asian spices. The pickles are popular across the Indian subcontinent, with many regional variants.
Tsuga chinensis, commonly referred to as the Taiwan or Chinese hemlock, or in Chinese as tieshan, is a coniferous tree species native to China, Taiwan, Tibet and Vietnam. The tree is quite variable and has many recognised varieties, though some are also maintained to be separate species by certain authorities. The tree was recently discovered in the mountains of northern Vietnam, making that the southernmost extension of its range.
Cercis siliquastrum, commonly known as the Judas tree or Judas-tree, is a small deciduous tree in the flowering plant family Fabaceae which is noted for its prolific display of deep pink flowers in spring. It is native to Southern Europe and Western Asia.
Important structures in plant development are buds, shoots, roots, leaves, and flowers; plants produce these tissues and structures throughout their life from meristems located at the tips of organs, or between mature tissues. Thus, a living plant always has embryonic tissues. By contrast, an animal embryo will very early produce all of the body parts that it will ever have in its life. When the animal is born, it has all its body parts and from that point will only grow larger and more mature. However, both plants and animals pass through a phylotypic stage that evolved independently and that causes a developmental constraint limiting morphological diversification.
Lepidodendrales or arborescent lycophytes are an extinct group of primitive, vascular, heterosporous, arborescent (tree-like) plants belonging to Lycopodiopsida. Members of Lepidodendrales are the best understood of the fossil lycopsids due to the vast diversity of Lepidodendrales specimens and the diversity in which they were preserved; the extensive distribution of Lepidodendrales specimens as well as their well-preservedness lends paleobotanists exceptionally detailed knowledge of the coal-swamp giants’ reproductive biology, vegetative development, and role in their paleoecosystem. The defining characteristics of the Lepidodendrales are their secondary xylem, extensive periderm development, three-zoned cortex, rootlike appendages known as stigmarian rootlets arranged in a spiralling pattern, and megasporangium each containing a single functional megaspore that germinates inside the sporangium. Many of these different plant organs have been assigned both generic and specific names as relatively few have been found organically attached to each other. Some specimens have been discovered which indicate heights of 40 and even 50 meters and diameters of over 2 meters at the base. The massive trunks of some species branched profusely, producing large crowns of leafy twigs; though some leaves were up to 1 meter long, most were much shorter, and when leaves dropped from branches their conspicuous leaf bases remained on the surface of branches. Strobili could be found at the tips of distal branches or in an area at the top of the main trunk. The underground organs of Lepidodendrales typically consisted of dichotomizing axes bearing helically arranged, lateral appendages serving an equivalent function to roots. Sometimes called "giant club mosses", they are believed to be more closely related to extant quillworts based on xylem, although fossil specimens of extinct Selaginellales from the Late Carboniferous also had secondary xylem.
A stem is one of two main structural axes of a vascular plant, the other being the root. It supports leaves, flowers and fruits, transports water and dissolved substances between the roots and the shoots in the xylem and phloem, stores nutrients, and produces new living tissue. The stem can also be called halm or haulm or culms.
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees.
Dendrosicyos is a monotypic genus in the plant family Cucurbitaceae. The only species is Dendrosicyos socotranus, the cucumber tree. The species is endemic to the island of Socotra in Yemen, and is the only species in the Cucurbitaceae to grow in a tree form. The species name was originally spelled D. socotrana, but this is corrected to masculine grammatical gender according to the International Code of Nomenclature for algae, fungi, and plants.
