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Rod cells are photoreceptor cells in the retina of the eye that can function in lower light better than the other type of visual photoreceptor, cone cells. Rods are usually found concentrated at the outer edges of the retina and are used in peripheral vision. On average, there are approximately 92 million rod cells (vs ~6 million cones) in the ...
A photoreceptor cell is a specialized type of neuroepithelial cell found in the retina that is capable of visual phototransduction.The great biological importance of photoreceptors is that they convert light (visible electromagnetic radiation) into signals that can stimulate biological processes.
A flagellum (/ f l ə ˈ dʒ ɛ l əm /; pl.: flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores (), and from a wide range of microorganisms to provide motility.
Example of a workup algorithm of possible bacterial infection in cases with no specifically requested targets (non-bacteria, mycobacteria etc.), with most common situations and agents seen in a New England setting. Clinically significant Gram-negative bacteria are usually rods, as shown near bottom right.
Diagram of a prokaryotic cell, a bacterium with a flagellum. A prokaryote (/ p r oʊ ˈ k ær i oʊ t,-ə t /; less commonly spelled procaryote) [1] is a single-celled organism whose cell lacks a nucleus and other membrane-bound organelles. [2]
Among protoctists and microscopic animals, a flagellate is an organism with one or more flagella. Some cells in other animals may be flagellate, for instance the spermatozoa of most animal phyla. Flowering plants do not produce flagellate cells, but ferns, mosses, green algae, and some gymnosperms and closely related plants do so. [2]
A well accepted example of pleomorphism is Helicobacter pylori, which exists as both a helix-shaped form (classified as a curved rod) and a coccoid form. [7] Legionella pneumophila , the species of intracellular bacteria parasite responsible for Legionnaire's disease , has been seen to differentiate within a developmentally diverse network. [ 8 ]
Most other mammals are currently thought to be dichromats, with only two types of cone (though limited trichromacy is possible at low light levels where the rods and cones are both active). [5] Most studies of carnivores, as of other mammals, reveal dichromacy; examples include the domestic dog, the ferret, and the spotted hyena.