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Vascular Cambium
The vascular cambium is the main growth tissue in the stems and roots of many plants exhibiting secondary growth, specifically in dicots such as buttercups and oak trees, gymnosperms such as pine trees, as well as in certain other vascular plants. It produces secondary xylem inwards, towards the pith, and secondary phloem outwards, towards the bark. Generally, more secondary xylem is produced than secondary phloem. In herbaceous plants, it occurs in the vascular bundles which are often arranged like beads on a necklace forming an interrupted ring inside the stem. In woody plants, it forms a cylinder of unspecialized meristem cells, as a continuous ring from which the new tissues are grown. Unlike the xylem and phloem, it does not transport water, minerals or food through the plant. Other names for the vascular cambium are the main cambium, wood cambium, or bifacial cambium. Occurrence Vascular cambia are found in all seed plants except for five angiosperm lineages whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helianthus Stem 2 L
''Helianthus'' () is a genus comprising around 70 species of annual and perennial flowering plants in the daisy family Asteraceae commonly known as sunflowers. Except for three South American species, the species of ''Helianthus'' are native to North America and Central America. The best-known species is the common sunflower (''Helianthus annuus''). This and other species, notably Jerusalem artichoke (''H. tuberosus''), are cultivated in temperateness, temperate regions and some tropical regions, as food crops for humans, cattle, and poultry, and as ornamental plants. The species ''H. annuus'' typically grows during the summer and into early fall, with the peak growth season being mid-summer. Several perennial ''Helianthus'' species are grown in gardens, but have a tendency to spread rapidly and can become aggressive. On the other hand, the whorled sunflower, ''Helianthus verticillatus'', was listed as an endangered species in 2014 when the U.S. Fish and Wildlife Service issued ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral (nutrient)
In the context of nutrition, a mineral is a chemical element. Some "minerals" are essential for life, but most are not. ''Minerals'' are one of the four groups of essential nutrients; the others are vitamins, essential fatty acids, and essential amino acids. The five major minerals in the human body are calcium, phosphorus, potassium, sodium, and magnesium. The remaining minerals are called " trace elements". The generally accepted trace elements are iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine, selenium, and bromine; there is some evidence that there may be more. The four organogenic elements, namely carbon, hydrogen, oxygen, and nitrogen ( CHON), that comprise roughly 96% of the human body by weight, are usually not considered as minerals (nutrient). In fact, in nutrition, the term "mineral" refers more generally to all the other functional and structural elements found in living organisms. Plants obtain minerals from soil. Animals ingest plants, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meristem
In cell biology, the meristem is a structure composed of specialized tissue found in plants, consisting of stem cells, known as meristematic cells, which are undifferentiated cells capable of continuous cellular division. These meristematic cells play a fundamental role in plant growth, regeneration, and acclimatization, as they serve as the source of all differentiated plant tissues and organs. They contribute to the formation of structures such as fruits, leaves, and seeds, as well as supportive tissues like stems and roots. Meristematic cells are totipotent, meaning they have the ability to differentiate into any plant cell type. As they divide, they generate new cells, some of which remain meristematic cells while others differentiate into specialized cells that typically lose the ability to divide or produce new cell types. Due to their active division and undifferentiated nature, meristematic cells form the foundation for the formation of new plant organs and the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grafting
Grafting or graftage is a horticulture, horticultural technique whereby tissues of plants are joined so as to continue their growth together. The upper part of the combined plant is called the scion () while the lower part is called the rootstock. The success of this joining requires that the vascular tissues grow together. The natural equivalent of this process is inosculation. The technique is most commonly used in asexual reproduction, asexual plant propagation, propagation of commercially grown plants for the horticultural and agricultural trades. The scion is typically joined to the rootstock at the soil line; however, top work grafting may occur far above this line, leaving an understock consisting of the lower part of the trunk and the root system. In most cases, the stock or rootstock is selected for its roots and the scion is selected for its Plant stem, stems, Leaf, leaves, flowers, or fruits. The scion contains the desired genes to be duplicated in future production ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cork Cambium
Cork cambium (: cambia or cambiums) is a tissue found in many vascular plants as a part of the epidermis. It is one of the many layers of bark, between the cork and primary phloem. The cork cambium is a lateral meristem and is responsible for secondary growth that replaces the epidermis in roots and stems. It is found in woody and many herbaceous dicots, gymnosperms and some monocots (monocots usually lack secondary growth). It is one of the plant's meristems – the series of tissues consisting of embryonic disk (incompletely differentiated) cells from which the plant grows. The function of cork cambium is to produce the cork, a tough protective material.Junikka, L. (1994) "Macroscopic bark terminology". ''IAWA Journal'' 15(1): 3–45Trockenbrodt, M. (1990) "Survey and discussion of the terminology used in bark anatomy". ''IAWA Bulletin, New Series'' 11: 141–166 Synonyms for cork cambium are bark cambium, peri-cambium and phellogen. Phellogen is defined as the meristematic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree
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, e.g., including only woody plants with secondary growth, only plants that are usable as lumber, or only plants above a specified height. But wider definitions include taller palms, tree ferns, bananas, and bamboos. Trees are not a monophyletic taxonomic group but consist of a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some trees reaching several thousand years old. Trees evolved around 400 million years ago, and it is estimated that there are around three trillion mature trees in the world currently. A tree typically has many secondary branches supported cle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocotyledon
Monocotyledons (), commonly referred to as monocots, ( Lilianae '' sensu'' Chase & Reveal) are flowering plants whose seeds contain only one embryonic leaf, or cotyledon. A monocot taxon has been in use for several decades, but with various ranks and under several different names. The APG IV system recognises its monophyly but does not assign it to a taxonomic rank, and instead uses the term "monocots" to refer to the group. Monocotyledons are contrasted with the dicotyledons, which have two cotyledons. Unlike the monocots however, the dicots are not monophyletic and the two cotyledons are instead the ancestral characteristic of all flowering plants. Botanists now classify dicots into the eudicots ("true dicots") and several basal lineages from which the monocots emerged. The monocots are extremely important economically, culturally, and ecologically, and make up a majority of plant biomass used in agriculture. Common crops such as dates, onions, garlic, rice, wheat, maize, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podostemaceae
Podostemaceae (riverweed family), a family in the order Malpighiales, comprise about 50 genera and species of more or less thalloid aquatic herbs. Distribution and habitat They are found mostly in tropical and subtropical areas worldwide. Many species are found in a very small geographic area, often even just a single river or waterfall. Because of their small range, many species are seriously threatened, especially from habitat loss (for example, due to dams flooding their habitat). Riverweeds adhere to hard surfaces (generally rock) in rapids and waterfalls of rivers. They are submerged when water levels are high, but during the dry season they live a terrestrial existence, flowering at this time. Their root anatomy is specialized for the purpose of clinging to rocks, and in fact details of the root structure are one of the ways of classifying riverweeds. Ecology In many rivers, Podostemaceae are an important food source for a wide range of animals. For example, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nelumbo
''Nelumbo'' is a genus of aquatic plants with large, showy flowers. Members are commonly called lotus, though the name is also applied to various other plants and plant groups, including the unrelated genus '' Lotus''. Members outwardly resemble those in the family Nymphaeaceae ("water lilies"), but ''Nelumbo'' is actually very distant from that family. ''Nelumbo'' is an ancient genus, with dozens of species known from fossil remains since the Early Cretaceous. However, there are only two known living species of lotus. One is the better-known ''Nelumbo nucifera'', which is native to East Asia, South Asia, Southeast Asia, and probably Australia and is commonly cultivated for consumption and use in traditional Chinese medicine. The other lotus is '' Nelumbo lutea'', which is native to North America and the Caribbean. Horticultural hybrids have been produced between these two allopatric species. Description Ultrahydrophobicity The leaves of ''Nelumbo'' are highly water-rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceratophyllum
''Ceratophyllum'' is a cosmopolitan distribution, cosmopolitan genus of flowering plants commonly found in ponds, marshes, and quiet streams in tropical and in temperate regions. It is the only extant taxon, extant genus in the family Ceratophyllaceae, itself the only extant family in the order Ceratophyllales. They are usually called coontails or hornworts, although hornwort is also used for unrelated plants of the division Anthocerotophyta. Description ''Ceratophyllum'' grows completely submerged, usually, though not always, floating on the surface of the water. The plant stems can reach 1–3 m in length. At intervals along nodes of the stem they produce rings of bright green leaf, leaves, which are narrow and often much-branched. The forked leaves are brittle and stiff to the touch in some species, softer in others. Roots are completely absent and are missing even in the embryonic stage, but sometimes they develop modified leaves with a rootlike appearance, which anchor the pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nymphaeales
The Nymphaeales are an order of flowering plants, consisting of three families of aquatic plants, the Hydatellaceae, the Cabombaceae, and the Nymphaeaceae (water lilies). It is one of the three orders of basal angiosperms, an early-diverging grade of flowering plants. At least 10 morphological characters unite the Nymphaeales.Peter F. Stevens. 2001 onwards. Angiosperm Phylogeny Website At: Missouri Botanical Garden Website. (see ''External links'' below). One of the traits is the absence of a vascular cambium, which is required to produce both xylem (wood) and phloem, which therefore are missing. Molecular synapomorphies are also known. The Plant List, created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden recognizes about 70 species in 11 genera within the order,The Plant List (website). 2010. (See ''External links'' below.) but a phylogenetic study of the genus '' Nymphaea'' implies that the number of species could be more than 90. The difference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lineage (evolution)
An evolutionary lineage is a temporal series of populations, organisms, cells, or genes connected by a continuous line of descent from ancestor to descendant. Lineages are subsets of the evolutionary tree of life. Lineages are often determined by the techniques of molecular systematics. Phylogenetic representation of lineages upright=1.4, A rooted tree of life into three ancient monophyletic lineages: archaea.html" ;"title="bacteria, archaea">bacteria, archaea, and eukaryotes based on rRNA genes Lineages are typically visualized as subsets of a phylogenetic tree. A lineage is a single line of descent or linear chain within the tree, while a clade is a (usually branched) monophyletic group, containing a single ancestor and all its descendants. Phylogenetic trees are typically created from DNA, RNA or protein sequence data. Apart from this, morphological differences and similarities have been, and still are used to create phylogenetic trees. Sequences from different individua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
