Question

one of the most important evolutionary advances in the progymnosperms was the presence of a bifacial vascular cambium. what is a bifacial vascular cambium, and where is it found besides in the progymnosperms?

Answer 1

A bifacial vascular cambium is a plant tissue responsible for secondary growth, found in progymnosperms, gymnosperms, and angiosperms. It allows for increasing stem and root thickness, supporting larger plant structures.

Step-by-step explanation:

The presence of a bifacial vascular cambium was an important evolutionary advancement exhibited by progymnosperms. A bifacial vascular cambium is a type of plant tissue responsible for secondary growth, which produces both the secondary xylem (wood) on the interior and the secondary phloem (part of the bark) on the exterior. This feature contributes to the thickening of stems and roots in plants.

Besides progymnosperms, the bifacial vascular cambium is found in extant gymnosperms and angiosperms (flowering plants). In gymnosperms, such as pines and conifers, and in angiosperms, it forms a continuous ring, allowing these plants to grow in diameter and support large and tall structures, a vital characteristic for survival on land.

In summary, the development of a bifacial vascular cambium allowed progymnosperms, and the plants that followed, to achieve significant structural diversity and adaptability, contributing to their widespread colonization of land.