Eye-spot

Augen-hornhaut,/. cornea, -kammerwasser, n. aqueous humor, -licht, n. eyesight, -lid, n. e3 elid. -linse, /. crystalline lens eye lens. e3 epiece. -marmor, m. eye-spotted marble, -mass, n. measure by eye. -merk, n. object in view, aim. -nerv, m. optic nerve, -nichts,... 

Note that it is possible to use proton or sodium ion gradients in signalling and a possible example is provided by the reactions of the proteins of the eye-spot of green algae (see Nagel et al. in Further Reading). 

Amphioxus ( 500xl06 years) As for (1) with an eye spot. Some coordination of sight with the body. No evidence of olfactory or hearing senses. Little or no telencephalox or cerebral cortex. Has forebrain, pineal and hypothalamus like systems... 

DMM, Drosophila melanogaster, somatie mutation, eye spot test + 100 ppm, 48 h inh Ballering etal. (1993)... 

TrochophorE A form of free swimming larva characteristic of several phyla of aquatic invertebrates typically possessing a radial symmetry, with a ring of cilia around it, an eye-spot, and a digestive tract with mouth and anal openings. 

C57B1/6J fT/iT dam mice are treated at about day 10 of gestation. Fi animals are euthanized 20 days after birth. A large number of dams per group needs to be exposed, and numerous offsprings should be examined for eye spots at single-cell level. 

In Vivo Gene Mutation Assays Mouse (Coat) Spot Assay Mouse Retinoblast (Eye Spot) Assay Hprt Assay... 

The mouse (coat) spot test uses Fj animals to detect point mutations at the c locus or recombination between the c and p genes induced in melanoblasts in utero. The mouse (eye) spot test detects eye spots resulting from induction of deletions at the p locus in utero, in precursor cells of retinal pigmented epithelial cells. This assay is considered useful for specifically detecting deletions in vivo, as well as for mechanistic studies and research purposes. 

Figure 1. Chlamydomonas growth and cell division during a 24-h cell cycle. In the cells, a cup-shaped chloroplast with a pyrenoid and the eye spot are seen. The two flagella provide locomotion.

In some instances, carotenoids are present outside the chloroplast. The pigment of the light-sensitive eye-spot of Euglena and of reproductive areas in certain algae (such as Ulvd) is comprised partially of carotenoids (Britton, 1983). 

The characteristic pigment of Pytrophyta is peridinin (XXI), but smaller amounts of diadinoxanthin (5,6-epoxy-7, 8 -didehydro-5,6-dihydro-j8,/3-carotene-3,3 -diol), dinoxanthin (neoxanthin 3-acetate), and )8-carotene, (VI) are also synthesized. In Cryptophyta, a-carotene (XXV) is found in greater amounts than /3-carotene. An acetylenic carotenoid, alloxan thin (7,8,7, 8 -tetradehydro-/8,/3-carotene-3,3 -diol), is also found. In Eugleno-phyta, pigments are found in both the chloroplasts and the eye spot of these organisms. Traces of keto carotenoids such as echinenone (/3,/8-caroten-... 

Fig. 11.8 (a) Mytilus larvae with distinctive black eye-spot and gill filaments,... 

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