Plastids Sentence Examples
It consists essentially of a number of minute corpuscles or plastids, the protoplasmic substance of which is impregnated with a green coloring matter.
These plastids are especially charged with the duty of manufacturing carbohydrates from the carbon dioxide which the air contains, and which is absorbed from it after it has entered the intercellular passages and has so reached the cells containing the plastids.
The protoplasm of a living cell con.sists of a semifluid granular substance, called the cytoplasm, one or more nuclei, and sometimes centrosomes and plastids.
Chromatophores.The chromatophores or plastids are protoplasmic structures, denser than the cytoplasm, and easily distinguishable from it by their color or greater refractive power.
In addition to the plastids, there are found in some plant-cells, e.g.Advertisement
In the Algae, such as Fucus, Volvox, Oedogonium, Bulbochaete, and in the Fungus Monoblepharis, the spermatozoid is a small oval or elongate cell containing nucleus, cytoplasm and sometimes plastids.
The eggcell or oosphere is a large cell containing a single large nucleus, and in the green plants the rudiments of plastids.
Cream-coloured flowers are regarded as white because cream is due to yellow plastids and not to sap colour.
As a rule they are highly coloured, the colouring matter being contained in the cell-sap, as in blue or red flowers, or in plastids (chromoplasts), as generally in yellow flowers, or in both forms, as in many orange-coloured or reddish flowers.
Plants and various groups of algae also have plastids.Advertisement
Neither of these is essential to all plant cells, and other plastids may be present.
They are present on all plastid types but are more common and extensive on non-green plastid types but are more common and extensive on non-green plastids that are sparsely distributed within the cell.
The plastids are not rigidly embedded in the cytoplasm, but are capable of a certain amount of movement therein.
The coloring matters are not dissolved in the stroma of the chrornoplast, but exist as amorphous granules, with or without the presence of a protein crystal, or in the form of fine crystalline needles, frequently curved and sometimes present in large numbers, which are grouped together in various ways in bundles and give the plastids their fusiform or triangular crystalline shape.