Search results
Results from the WOW.Com Content Network
The clear epidermal cells exist in a single layer and do not contain chloroplasts, because the onion fruiting body (bulb) is used for storing energy, not photosynthesis. [3] Each plant cell has a cell wall, cell membrane, cytoplasm, nucleus, and a large vacuole. The nucleus is present at the periphery of the cytoplasm.
In smaller cells, the diffusion of molecules is more rapid, but diffusion slows as the size of the cell increases, so larger cells may need cytoplasmic streaming for efficient function. [1] The green alga genus Chara possesses some very large cells, up to 10 cm in length, [2] and cytoplasmic streaming has been studied in these large cells. [3]
To keep cells alive during observation, the microscopes are commonly enclosed in a micro cell incubator (the transparent box). Live-cell imaging is the study of living cells using time-lapse microscopy. It is used by scientists to obtain a better understanding of biological function through the study of cellular dynamics. [1]
Antonie van Leeuwenhoek (1632–1723). The field of microscopy (optical microscopy) dates back to at least the 17th-century.Earlier microscopes, single lens magnifying glasses with limited magnification, date at least as far back as the wide spread use of lenses in eyeglasses in the 13th century [2] but more advanced compound microscopes first appeared in Europe around 1620 [3] [4] The ...
The fluorochrome-based TUNEL assay applicable for flow cytometry, combining the detection of DNA strand breaks with respect to the cell cycle-phase position, was originally developed by Gorczyca et al. [4] Concurrently, the avidin-peroxidase labeling assay applicable for light absorption microscope was described by Gavrieli et al. [5] Since 1992 the TUNEL has become one of the main methods for ...
3D rendering of centrioles showing the triplets. In cell biology a centriole is a cylindrical organelle composed mainly of a protein called tubulin. [1] Centrioles are found in most eukaryotic cells, but are not present in conifers (), flowering plants (angiosperms) and most fungi, and are only present in the male gametes of charophytes, bryophytes, seedless vascular plants, cycads, and Ginkgo.
In some cases, cells may be grown directly on a slide. For samples of loose cells (as with a blood smear or a pap smear) the sample can be directly applied to a slide. For larger pieces of tissue, thin sections (slices) are made using a microtome; these slices can then be mounted and inspected.
The release is due to the breaking open of the onion cells, which releases enzymes called alliinases. Alliinases then break down amino acid sulfoxides , generating sulfenic acids . A specific sulfenic acid, allicin or 1-propenesulfenic acid, is rapidly rearranged by another enzyme, the lachrymatory factor synthase (LFS) to give syn ...