Such circumstances may act primarily through the nervous or through the vascular system.
As to its exact relations to the vascular system of the embryo more observations seem to be required.
Also, I did not find as much individual variation in the skeleton and muscles in the area studied as I did in the vascular system.
The maximum pressure necessarily falls as the periphery of the vascular system is approached.
The same is the case with the vascular system, notably the heart and the veins, and with the excretory organs.
The microscopic examinations showed the absence of fungi or bacteria in the vascular system or other plant tissues.
The vascular system is simple with as a rule direct communication between dorsal and ventral vessels in each segment.
And further ones of a different order, but of like general implication, are supplied by the vascular system.
Diagrammatic projection of the vascular system of the yolk sac of a somewhat older embryo.
There is nothing remarkable about the vascular system to distinguish it from that of many higher forms of animals.
vascular system n.
See circulatory system.
vascular tissue |
The tissue in vascular plants that circulates fluid and nutrients. There are two kinds of vascular tissue: xylem, which conducts water and nutrients up from the roots, and phloem, which distributes food from the leaves to other parts of the plant. Vascular tissue can be primary (growing from the apical meristem and elongating the plant body) or secondary (growing from the cambium and increasing stem girth). Seedless plants, and nearly all monocotyledons and herbaceous eudicotyledons, have only primary vascular tissue. The evolution of vascular tissue, especially xylem with its rigid water-conducting cells known as tracheids, provided the plant stem with greater support and allowed plants to grow upright to great heights. See also cambium, ground tissue, procambium., See more at phloem, xylem.