UV fine structure of the spectral sensitivity of flies visual cells

The fine structure of the visual and the supporting cells and of the blood capillaries in the octopus retina is described. Lamellated structures contained in the proximal segment of the visual cell consist of compact arrays of dense membranes each of which is quintuple-layered and divides at its margins into two thinner sheets or membranes which are connected directly with the agranular or granular endoplasmic reticulum. Proximal to the deeper extremities of the rhabdomeres, the lateral plasma membranes of two adjoining visual cells contact each other forming a quintuple-layered compound membrane, which results in occlusion of the intercellular space. The central layer of the compound membrane is of high density, so that the membrane, as a whole, appears to be a single thick layer at low magnifications. The supporting cells are connected with the neighboring visual cells by two types of junctions. Long slender processes extend from the supporting cells to the surface of the retina through narrow spaces among the distal segments of the visual cells. The capillary endothelial cells are characterized by luminal surfaces irregularly contoured and by lateral surfaces elaborately interdigitated. The functional significance of the close contact between adjoining visual cells is discussed.

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The spectral sensitivity of the visual cells R7 and R8 in the eye of the blowflyCalliphora erythrocephala

Journal of Comparative Physiology A ◽

10.1007/bf00663108 ◽

1979 ◽

Vol 133 (1) ◽

pp. 41-52 ◽

Cited By ~ 32

Author(s):

U. Smola ◽

P. Meffert

Keyword(s):

Spectral Sensitivity ◽

Visual Cells

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Properties of visual cells in the lateral eye of Limulus in situ.

The Journal of General Physiology ◽

10.1085/jgp.66.3.303 ◽

1975 ◽

Vol 66 (3) ◽

pp. 303-326 ◽

Cited By ~ 25

Author(s):

E Kaplan ◽

R B Barlow

Keyword(s):

Optic Nerve ◽

Spectral Sensitivity ◽

Dark Adaptation ◽

The Other ◽

Low Light ◽

Visual Cells ◽

Increment Threshold ◽

Lateral Eye ◽

Nerve Recordings

Excitatory properties of visual cells in the lateral eye of Limulus, investigated by optic nerve recordings in situ, differ significantly from the properties of cells in the classical, excised eye preparation. The differences suggest the possibility that two receptor mechanisms function in the eye in situ: one mechanism encodes low light intensities and the other responds to high intensities. The two mechanisms enable each ommatidium to respond over an intensity range of approximately 10 log units. This hypothesis was tested by measuring the increment threshold and the spectral sensitivity, by studying light and dark adaptation, and by analyzing the variability of the impulse discharge. Although the results do not conclusively identify two receptor mechanisms, they indicate that a process or a part of a process that functions in the eye in situ is abolished by excising the eye or cutting off its blood supply.

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Spectral sensitivity of intracellular responses from visual cells in median ocellus of Limulus polyphemus

Vision Research ◽

10.1016/0042-6989(70)90171-9 ◽

1970 ◽

Vol 10 (9) ◽

pp. 905-909 ◽

Cited By ~ 9

Author(s):

Abner B. Lall

Keyword(s):

Spectral Sensitivity ◽

Limulus Polyphemus ◽

Visual Cells ◽

Median Ocellus

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Decision letter for "Retinal topography and spectral sensitivity of the Port Jackson shark ( Heterodontus portusjacksoni )"

10.1002/cne.24911/v1/decision1 ◽

2020 ◽

Keyword(s):

Spectral Sensitivity ◽

Retinal Topography ◽

Port Jackson

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Fine Structure of Platelet Interaction with a New Microcrystalline Collagen Preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050305 ◽

1974 ◽

Vol 32 ◽

pp. 58-59

Author(s):

W. H. Zucker ◽

R. G. Mason

Keyword(s):

Fine Structure ◽

Platelet Aggregation ◽

Hydrochloric Acid ◽

Whole Blood ◽

Platelet Adhesion ◽

Hemostatic Agent ◽

Native Collagen ◽

Fibrillar Morphology ◽

Clinical Interest ◽

New Form

Platelet adhesion initiates platelet aggregation and is an important component of the hemostatic process. Since the development of a new form of collagen as a topical hemostatic agent is of both basic and clinical interest, an ultrastructural and hematologic study of the interaction of platelets with the microcrystalline collagen preparation was undertaken.In this study, whole blood anticoagulated with EDTA was used in order to inhibit aggregation and permit study of platelet adhesion to collagen as an isolated event. The microcrystalline collagen was prepared from bovine dermal corium; milling was with sharp blades. The preparation consists of partial hydrochloric acid amine collagen salts and retains much of the fibrillar morphology of native collagen.

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