(Shape) a symmetrical 3-dimensional shape with the base a circle, the sides straight and narrowing to a point at the apex;
The fruit of a gymnosperm with the scales overlapping (properly a strobilus), and hence any inflorescence or fruit with overlapping scales.
One of the special retinal receptor elements which are presumed to be primarily concerned with perception of light and color stimuli when the eye is adapted to light.
A cluster of sporophylls or ovuliferous scales on an axis; a strobilus, as in pine or cycad cones.
A dry, compound fruit, like that of the pine.
A dry fruit with overlapping, woody scales.
An inflorescence or fruit with the scales overlapping, like the fruit of Magnoliaceae or the seed-bearing structure in a gymnosperm.
The structure that encloses the primitive flowers and then the seeds of conifers (pines, cypresses, etc.) and cycads. It is made up of overlapping scales, which become woody when the seeds ripen.
Light-sensitive cell in the retina of the eye; the cones are responsible for color vision and visual sharpness.
A solid or hollow three-dimensional figure with a circular base and sides sloping up to a point.
Visual receptors that respond to greater light intensities and give rise to chromatic visual sensations are located in the retina of the eye.
The structure that encloses the seeds of most conifers and cycads, consisting of scales arranged around a central axis, each scale having one or more seeds attached to its surface or embedded in its tissues; also used for the pollen-bearing organs (pollen cones) of these plants which consist of smaller scales bearing many tiny pollen sacs which shed their pollen into the wind.
Cells in the retina that are responsible for colour vision.
One of the two types of light-sensitive cells in the retina of the eye (compare rod). The human retina contains 6-7 million cones; they function best in bright light and are essential for acute vision (receiving a sharp accurate image). The area of the retina called the fovea contains the greatest concentration of cones. Cones can also distinguish colors. It is thought that there are three types of cone, each sensitive to the wavelength of a different primary color—red, green, or blue. Other colors are seen as combinations of these three primary colors.
The flower, and usually the fruit, of a cone-bearing tree, consisting of numerous overlapping, spirally arranged scales.
The flower, and usually the fruit, of a cone-bearing (coniferous) tree, consisting of numerous overlapping spirally arranged scales.
Light-receiving cells on the retina that enable a person to see color.
A circular metallic apparatus affixed to the housing of the X-ray tube serves the purpose of restricting the X-ray beam solely to the intended field of interest.
Cones are specialized light-sensitive cells situated within the retina of the eye. They play a pivotal role in enabling color vision.