Search results
Results From The WOW.Com Content Network
The Human Cell Atlas project, which started in 2016, had as one of its goals to "catalog all cell types (for example, immune cells or brain cells) and sub-types in the human body". [13] By 2018, the Human Cell Atlas description based the project on the assumption that "our characterization of the hundreds of types and subtypes of cells in the ...
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.
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 ...
He coined the term cell (from Latin cellula, meaning "small room" [41]) in his book Micrographia (1665). [42] [40] 1839: Theodor Schwann [43] and Matthias Jakob Schleiden elucidated the principle that plants and animals are made of cells, concluding that cells are a common unit of structure and development, and thus founding the cell theory.
In the kidneys specialised cells called podocytes extend processes that terminate in podocyte foot processes that cover capillaries in the nephron. End-processes may also be known as vascular footplates, and in general may exhibit a pyramidal or finger-like morphology. [1] [2] Mural cells such as pericytes extend processes to wrap around ...
A podocyte has a complex structure. Its cell body has extending major or primary processes that form secondary processes as podocyte foot processes or pedicels. [6] The primary processes are held by microtubules and intermediate filaments. The foot processes have an actin-based cytoskeleton. [6]
Heterocysts or heterocytes are specialized nitrogen-fixing cells formed during nitrogen starvation by some filamentous cyanobacteria, such as Nostoc, Cylindrospermum, and Anabaena. [1] They fix nitrogen from dinitrogen (N 2 ) in the air using the enzyme nitrogenase , in order to provide the cells in the filament with nitrogen for biosynthesis.
The non-membrane bounded organelles, also called large biomolecular complexes, are large assemblies of macromolecules that carry out particular and specialized functions, but they lack membrane boundaries. Many of these are referred to as "proteinaceous organelles" as their main structure is made of proteins. Such cell structures include: