eyeball. 1  Photoreceptors are the cells in the retina that respond to light. Their distinguishing feature is the presence of large amounts of tightly packed membrane that contains the photopigment rhodopsin or a related molecule.
In chemical analysis,  matrix refers to the components of a sample other than the analyte of interest. The matrix can have a considerable effect on the way the analysis is conducted and the quality of the results obtained; such effects are called matrix effects. For example, the ionic strength of the solution can have an effect on the activity coefficients of the analytes.
The Project Matrix is a model of the software development work of a project. represented by a matrix of activities, such as that shown in Figure 1. column represents a âsubsystemâ for which the task must be performed. requirements document, a set of structure charts, a collection of code, or the like.