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The study of plant response in space environments is another subject of astrobotany research. In space, plants encounter unique environmental stressors not found on Earth including microgravity, ionizing radiation, and oxidative stress. [23] Experiments have shown that these stressors cause genetic alterations in plant metabolism pathways.
Sclerenchyma is the tissue which makes the plant hard and stiff. Sclerenchyma is the supporting tissue in plants. Two types of sclerenchyma cells exist: fibers cellular and sclereids. Their cell walls consist of cellulose, hemicellulose, and lignin. Sclerenchyma cells are the principal supporting cells in plant tissues that have ceased elongation.
In the case of pervasive growth, cementation of the host sediments, by infilling of its pore space by precipitated minerals, occurs simultaneously throughout the volume of the area, which in time becomes a concretion. Concretions are often exposed at the surface by subsequent erosion that removes the weaker, uncemented material.
Some eukaryotic cells (plant cells and fungal cells) also have a cell wall. Inside the cell is the cytoplasmic region that contains the genome (DNA), ribosomes and various sorts of inclusions. [2] The genetic material is freely found in the cytoplasm. Prokaryotes can carry extrachromosomal DNA elements called plasmids, which are usually circular.
Structure of a plant cell. 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 ...
Aerenchyma in stem cross section of a typical wetland plant. Aerenchyma or aeriferous parenchyma [1] or lacunae, is a modification of the parenchyma to form a spongy tissue that creates spaces or air channels in the leaves, stems and roots of some plants, which allows exchange of gases between the shoot and the root. [2]
The loosely packed cells of root cortex allow movement of water and oxygen in the intercellular spaces. [4] One of the main functions of the root cortex is to serve as a storage area for reserve foods. [4] The innermost layer of the cortex in the roots of vascular plants is the endodermis. The endodermis is responsible for storing starch as ...
Light micrograph of a moss's leaf cells at 400X magnification. The following outline is provided as an overview of and topical guide to cell biology: . Cell biology – A branch of biology that includes study of cells regarding their physiological properties, structure, and function; the organelles they contain; interactions with their environment; and their life cycle, division, and death.