| 释义 |
parenchymaenUK
pa·ren·chy·ma P0069100 (pə-rĕng′kə-mə)n.1. Anatomy The tissue characteristic of an organ, as distinguished from associated connective or supporting tissues.2. Botany A simple plant tissue, composed of thin-walled cells and forming the greater part of leaves, roots, the pulp of fruit, and the pith of stems.
[New Latin, from Greek parenkhuma, visceral flesh, from parenkhein, to pour in beside : para-, beside; see para-1 + en-, in; see en in Indo-European roots + khein, to pour; see gheu- in Indo-European roots.]
pa·ren′chy·mal, par′en·chym′a·tous (păr′ĕn-kĭm′ə-təs) adj.parenchyma (pəˈrɛŋkɪmə) n1. (Botany) unspecialized plant tissue consisting of simple thin-walled cells with intervening air spaces: constitutes the greater part of fruits, stems, roots, etc2. (Zoology) animal tissue that constitutes the essential or specialized part of an organ as distinct from the blood vessels, connective tissue, etc, associated with it3. (Zoology) loosely-packed tissue filling the spaces between the organs in lower animals such as flatworms[C17: via New Latin from Greek parenkhuma something poured in beside, from para-1 + enkhuma infusion] parenchymatous, parenchymal adjpa•ren•chy•ma (pəˈrɛŋ kə mə)
n. 1. the fundamental tissue of plants, composed of thin-walled cells able to divide. 2. the functional tissue of an animal organ as distinguished from its connective or supporting tissue. 3. a spongy connective tissue of certain invertebrates. [1645–55; < New Latin < Greek parénchyma literally, something poured in beside =par- par- + énchyma infusion; see mesenchyme] pa•ren′chy•mal, par•en•chym•a•tous (ˌpær əŋˈkɪm ə təs) adj. pa·ren·chy·ma (pə-rĕng′kə-mə) The basic tissue of plants, consisting of thin-walled, nonspecialized cells that sometimes adapt to specialized functions. The internal layers of leaves, the cortex and pith of the stem, and the soft parts of fruits are made of parenchyma. In higher plants, parenchyma supports the plant body, roots, and leaves; it also stores water and contains chloroplasts in which photosynthesis takes place.Thesaurus| Noun | 1. |  parenchyma - animal tissue that constitutes the essential part of an organ as contrasted with e.g. connective tissue and blood vesselsanimal tissue - the tissue in the bodies of animals | | 2. | parenchyma - the primary tissue of higher plants composed of thin-walled cells that remain capable of cell division even when mature; constitutes the greater part of leaves, roots, the pulp of fruits, and the pith of stemsplant tissue - the tissue of a plantpulp, flesh - a soft moist part of a fruitpith - soft spongelike central cylinder of the stems of most flowering plantschlorenchyma - parenchyma whose cells contain chloroplastsroot - (botany) the usually underground organ that lacks buds or leaves or nodes; absorbs water and mineral salts; usually it anchors the plant to the groundfoliage, leaf, leafage - the main organ of photosynthesis and transpiration in higher plants |
Translations
ParenchymaenUK
Parenchyma A ground tissue of plants chiefly concerned with the manufacture and storage of food. The primary functions of plants, such as photosynthesis, assimilation, respiration, storage, secretion, and excretion—those associated with living protoplasm—proceed mainly in parenchymal cells. Parenchyma is frequently found as a homogeneous tissue in stems, roots, leaves, and flower parts. Other tissues, such as sclerenchyma, xylem, and phloem, seem to be embedded in a matrix of parenchyma; hence the use of the term ground tissue with regard to parenchyma is derived. The parenchymal cell is one of the most frequently occurring cell types in the plant kingdom. See Plant anatomy, Plant physiology Typical parenchyma occurs in pith and cortex of roots and stems as a relatively undifferentiated tissue composed of polyhedral cells that may be more or less compactly arranged and show little variation in size or shape. The mesophyll, that is, the tissue located between the upper and lower epidermis of leaves, is a specially differentiated parenchyma called chlorenchyma because its cells contain chlorophyll in distinct chloroplastids. This chlorenchymatous tissue is the major locus of photosynthetic activity and consequently is one of the more important variants of parenchyma. Specialized secretory parenchymal cells are found lining resin ducts and other secretory structures. See Photosynthesis, Secretory structures (plant) Parenchyma (1) The fundamental tissue in plants. Parenchyma is composed of cells having a polyhedral shape, with the various diameters differing very little from each other. The cells form homogeneous aggregates in the plant body and fill the spaces between other tissues. They serve as part of the conductive and mechanical tissues. As a result of functional specialization of protoplasts, parenchyma cells may perform assimilative, excretive, and other functions. The presence of intercellular substances, especially in diffuse parenchyma with vacuoles, determines the tissue’s role in gas exchange. Parenchyma cells serving support functions may be elongated, branched, or stellate; their walls are thick and often lignified. Living parenchyma cells are capable of division. Phellogen (cork cambium) or, in unusually thick plants, cambium is formed (for example, in beets and certain lianas). (2) In animals, parenchyma is the phylogenetic precursor of true tissue. It is divided into primary parenchyma and mixed parenchyma. The former is a bond of homogeneous cells without systematic organization. The cells are not fused in a syncytium or separated by interstitial matter (as in the embryos of certain hydroids in the morular stage). Mixed parenchyma is an aggregate of heterogeneous cells distributed randomly, as in the bodies of Acoela. At times, the term “parenchyma” is used to designate the principal functional tissue of the liver, spleen, lungs, and glands. It is also used to designate striated muscle tissue. parenchyma[pə′reŋ·kə·mə] (botany) A tissue of higher plants consisting of living cells with thin walls that are agents of photosynthesis and storage; abundant in leaves, roots, and the pulp of fruit, and found also in leaves and stems. (histology) The specialized epithelial portion of an organ, as contrasted with the supporting connective tissue and nutritive framework. parenchymaenUK
parenchyma [pah-reng´kĭ-mah] the essential or functional elements of an organ, as distinguished from its framework, which is called the stroma. adj., adj paren´chymal, parenchym´atous.parenchyma of prostate glandular substance consisting of small compound tubulosaccular or tubuloalveolar glands, making up the bulk of the prostate; it is surrounded by muscular substance and permeated by muscular strands.renal parenchyma the functional tissue of the kidney, consisting of the nephrons.pa·ren·chy·ma (pă-reng'ki-mă), [TA] 1. The distinguishing or specific cells of a gland or organ, contained in and supported by the connective tissue framework, or stroma. 2. The endoplasm of a protozoan cell. 3. In the lung, consists of the gas-exchanging portion, excluding the radiographically visible blood vessels and bronchi. [G. anything poured in beside, fr. parencheō, to pour in beside] parenchyma (pə-rĕng′kə-mə)n.1. Anatomy The tissue characteristic of an organ, as distinguished from associated connective or supporting tissues.2. Botany A simple plant tissue, composed of thin-walled cells and forming the greater part of leaves, roots, the pulp of fruit, and the pith of stems.
pa·ren′chy·mal, par′en·chym′a·tous (păr′ĕn-kĭm′ə-təs) adj.pa·ren·chy·ma (pă-rengk'i-mă) [TA] 1. The distinguishing or specific cells of a gland or organ, contained in and supported by the connective tissue framework, or stroma. 2. The endoplasm of a protozoan cell. [G. anything poured in beside, fr. parencheō, to pour in beside] Fig. 246 Parenchyma . Transverse section of cells. parenchyma - a tissue composed of parenchyma cells which are thin-walled ‘general purpose’ plant cells that often have a packing function. Parenchyma cells remain alive at maturity and can become meristematic, as in INTERFASCICULAR CAMBIUM (see SECONDARY THICKENING). See Fig. 246 .
- 2 the loose, vacuolated cells that form much of the body tissue of platyhelminths.
- 3 any specific organ cells apart from connective tissues and blood vessels.
parenchymaenUK
Words related to parenchymanoun animal tissue that constitutes the essential part of an organ as contrasted with eRelated Wordsnoun the primary tissue of higher plants composed of thin-walled cells that remain capable of cell division even when matureRelated Words- plant tissue
- pulp
- flesh
- pith
- chlorenchyma
- root
- foliage
- leaf
- leafage
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