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Vasodilation plays a major role in immune system function. Wider blood vessels allow more blood containing immune cells and proteins to reach the infection site. Vasodilation occurs as part of the process of inflammation, which is caused by several factors including presence of a pathogen, injury to tissues or blood vessels, and immune ...
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 ...
As such, mass flow is a subject of study in both fluid dynamics and biology. Examples of mass flow include blood circulation and transport of water in vascular plant tissues. Mass flow is not to be confused with diffusion which depends on concentration gradients within a medium rather than pressure gradients of the medium itself.
The xylem consists of vessels in flowering plants and of tracheids in other vascular plants. Xylem cells are dead, hard-walled hollow cells arranged to form files of tubes that function in water transport. A tracheid cell wall usually contains the polymer lignin. The phloem, on the other hand, consists of living cells called sieve-tube members ...
Plant cells also contain chlorophyll, a chemical compound that interacts with light in a way that enables plants to manufacture their own nutrients rather than consuming other living things as animals do. Thirdly, plant physiology deals with interactions between cells, tissues, and organs within a plant. Different cells and tissues are ...
The latter occurs not only in plants but also in animals when the carbon and energy from plants is passed through a food chain. The fixation or reduction of carbon dioxide is a process in which carbon dioxide combines with a five-carbon sugar , ribulose 1,5-bisphosphate , to yield two molecules of a three-carbon compound, glycerate 3-phosphate ...
The Calvin cycle is present in all photosynthetic eukaryotes and also many photosynthetic bacteria. In plants, these reactions occur in the stroma, the fluid-filled region of a chloroplast outside the thylakoid membranes. These reactions take the products (ATP and NADPH) of light-dependent reactions and perform further chemical processes on them.
The individual cells of phloem are connected end-to-end, just as the sections of a pipe might be. As the plant grows, new vascular tissue differentiates in the growing tips of the plant. The new tissue is aligned with existing vascular tissue, maintaining its connection throughout the plant.