Vascular-plants sentence example
- In general structure they approach the Phanerogams with which they form collectively the Vascular Plants as contrasted with the Cellular PlantsThallophyta and Bryophyta.
- In higher forms the conducting strands of the leaves are continued downwards into the stem, and eventually come into connection with the central hydrom cylinder, forming a complete cylindrical investment apparently distinct from the latter, and exhibiting a differentiation into hydrom, leptom and amylom which almost completely parallels that found among the true vascular plants.
- The body of the sporophyte in the great majority of the vascular plants shows a considerable increase in complexity over that found in the gametophyte of Bryophytes.
- In the Vascular Plants this tissue is collectively known as the vascular system.
- The structure of the stomata of the sporophyte of vascular plants is fundamentally the same as that of the stomata on the sporogonium of the true mosses and of the liverwort A nihoceros.Advertisement
- The stelar system of Vascular Plants has no direct phylogenetic connection with that of the mosses.
- The vascular plants already described number about 1500 species.
- The typical foliage leaf consists of several layers, and amongst vascular plants is distinguishable into an outer layer (epidermis) and a central tissue (parenchyma) with fibro-vascular bundles distributed through it.
- Considering, however, that it is generally believed that Bryophyta and vascular plants are descended from an algal ancestry, it is natural to suppose that, prior to the luxuriant vegetable growths of the Carboniferous period, there must have existed an age of algae.
- According to the Prodromus florae hispanicae of Willkomm and Lange (completed in 1880), the number of species of vascular plants then ascertained to exist in the country was 5096.Advertisement
- A richly chlorophyllous tissue, with numerous intercellular spaces communicates with the exterior by stomata, strikingly similar to those of the vascular plants (see below).
- While convincing us that the plants of past ages in the earths history were exposed to very similar conditions of life, and made very much the same adaptive responses as their modern representatives, one of the main results of this line of work has been to reveal important data enabling us to fill various gaps in our morphological knowledge and to obtain a more complete picture of the evolution of tissues in the vascular plants.
- The importance of this provision in the case of aquatic vascular plants of sturdy bulk is even greater than in that of terrestrial organisms, as their environment offers considerable obstacles to the renewal of the air in their interior.
- There are about 270 species of vascular plants in this area.
- But these two principles do not find their full expression till we come, in the ascending series, to the Vascular Plants.Advertisement