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Plasmodesmata
Plasmodesmata (singular: plasmodesma) are microscopic channels which traverse the cell walls of plant cells and some algal cells, enabling transport and communication between them. Plasmodesmata evolved independently in several lineages, and species that have these structures include members of the Charophyceae, Charales, Coleochaetales and Phaeophyceae (which are all algae), as well as all embryophytes, better known as land plants. Unlike animal cells, almost every plant cell is surrounded by a polysaccharide cell wall. Neighbouring plant cells are therefore separated by a pair of cell walls and the intervening middle lamella, forming an extracellular domain known as the apoplast. Although cell walls are permeable to small soluble proteins and other solutes, plasmodesmata enable direct, regulated, symplastic transport of substances between cells. There are two forms of plasmodesmata: primary plasmodesmata, which are formed during cell division, and secondary plasmodesma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodesmata Structure
Plasmodesmata (singular: plasmodesma) are microscopic channels which traverse the cell walls of plant cells and some algal cells, enabling transport and communication between them. Plasmodesmata evolved independently in several lineages, and species that have these structures include members of the Charophyceae, Charales, Coleochaetales and Phaeophyceae (which are all algae), as well as all embryophytes, better known as land plants. Unlike animal cells, almost every plant cell is surrounded by a polysaccharide cell wall. Neighbouring plant cells are therefore separated by a pair of cell walls and the intervening middle lamella, forming an extracellular domain known as the apoplast. Although cell walls are permeable to small soluble proteins and other solutes, plasmodesmata enable direct, regulated, symplastic transport of substances between cells. There are two forms of plasmodesmata: primary plasmodesmata, which are formed during cell division, and secondary plasmodesmata, which c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pit (botany)
Pits are relatively thinner portions of the cell wall that adjacent cell (biology), cells can Cell communication, communicate or exchange fluid through. Pits are characteristic of cell walls with Cell wall#Rigidity of cell walls, secondary layers. Generally each pit has a complementary pit opposite of it in the neighboring cell. These complementary pits are called "pit pairs". Pits are composed of three parts: the pit chamber, the pit aperture, and the pit membrane. The pit chamber is the hollow area where the secondary layers of the cell wall are absent. The pit aperture is the opening at either end of the pit chamber. The pit membrane is the primary cell wall and middle lamella, or the membrane between adjacent cell walls, at the middle of the pit chamber. The primary cell wall at the pit membrane may also have depressions similar to the pit depressions of the secondary layers. These depressions are primary pit-fields, or primary pits. In the primary pit, the primordial pit pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Sciences
Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, origin, evolution, and distribution of life. Central to biology are five fundamental themes: the cell as the basic unit of life, genes and heredity as the basis of inheritance, evolution as the driver of biological diversity, energy transformation for sustaining life processes, and the maintenance of internal stability (homeostasis). Biology examines life across multiple levels of organization, from molecules and cells to organisms, populations, and ecosystems. Subdisciplines include molecular biology, physiology, ecology, evolutionary biology, developmental biology, and systematics, among others. Each of these fields applies a range of methods to investigate biological phenomena, including observation, experimentation, and mathematical modeling. Modern biology is grounded i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
