Structure and Shape Provide Flexibility

a vine twists across the frame from left to right with leaves in the background

Biological Strategy

Plants

AskNature Team

Image: Lou Gold / Flickr / Some rights reserved

Physically Assemble Structure

Living systems use physical materials to create structures to serve as protection, insulation, and other purposes. These structures can be internal (within or attached to the system itself), such as cell membranes, shells, and fur. They can also be external (detached), such as nests, burrows, cocoons, or webs. Because physical materials are limited and the energy required to gather and create new structures is costly, living systems must use both conservatively. Therefore, they optimize the structures’ size, weight, and density. For example, weaver birds use two types of vegetation to create their nests: strong, a few stiff fibers and numerous thin fibers. Combined, they make a strong, yet flexible, nest. An example of an internal structure is a bird’s bone. The bone is comprised of a mineral matrix assembled to create strong cross-supports and a tubular outer surface filled with air to minimize weight.

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Plants

Phylum Plantae (“plants”): Angiosperms, gymnosperms, green algae, and more

Plants have evolved by using special structures within their cells to harness energy directly from sunlight. There are currently over 350,000 known species of plants which include angiosperms (flowering trees and plants), gymnosperms (conifers, Gingkos, and others), ferns, hornworts, liverworts, mosses, and green algae. While most get energy through the process of photosynthesis, some are partially carnivores, feeding on the bodies of insects, and others are plant parasites, feeding entirely off of other plants. Plants reproduce through fruits, seeds, spores, and even asexually. They evolved around 500 million years ago and can now be found on every continent worldwide.

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Architecture of vines increases flexibility via soft tissue components and ribbon-like shape.

Image: Lena Struwe /

Image: Lou Gold / Flickr /

Cross section of Jagube shows alternating layers of soft and woody tissue that contributes to the strength and flexibility of the vine.

“There is another way in which the stem anatomy of woody vines differs from that of trees. In trees, the wood or xylem, of which only the newest and outermost annual ring actually conducts water, is in the form of a solid cylinder whose rigidity is able to support large crowns of leaves and branches. Vines need to be more flexible to cope with the twists and turns of climbing or the stresses that result when they partly or completely slip away from their supports. Woody vines achieve flexibility by having a considerable amount of soft tissue as well as wood in their stems. In some, the cylinder of wood is divided into segments that alternate with soft tissue; in others, there are alternating cylinders of wood and soft tissue. Some woody vines also have flattened, ribbon-like stems to achieve greater flexibility.” (Dawson and Lucas 2005:17)