Part A: A Summary
THE SECRET MATH OF PLANTS
Life scientists have discovered 1) ___________ of leaf design that enable plants of different sizes to grow leaves of different shape and size. Using allometric analysis, the team from 2) _____________ looked at how the proportions of parts and differences in total size applied to the interior of leaves.
The biologists focused on 3) __________ in leaves of different sizes, and examined plant species from around the world, all grown on the UCLA campus. They said that 4) __________ the differences in leaf surface area among species was easy, but the study of differences in leaf thickness was less obvious but equally important.
Grace John, 5) __________ of the research, said "Rubbing leaves between your fingers, you can feel that some are floppy and thin, while others are rigid and thick. We started with the simplest 6) __________ such as whether thicker or larger leaves are constructed of different sizes or types of cells."
The researchers cut 7) ___________ thinner than a single cell by embedding pieces of leaf in plastic. Then they could observe each leaf's microscopic layout. The relationship between cell and tissue 8) _________ and leaf size across species could thus be tested.
The 9) __________ basic tissues of leaves were found to have larger 10) ________ in thicker leaves except for the vascular tissue (which carries the nutrients to the plant.) These relationships also applied to the 11) __________ of the individual cells, and the larger cells of thicker leaves are surrounded by 12) __________ in a strict proportionality.
The simple mathematical equations of these relationships effectively allow scientists to 13) _________ the dimension of cells and cell walls based on the thickness of a leaf. In most cases, the relationships the team found were 14) __________.
By contrast, a leaf's 15) __________ is unrelated to the sizes of the cells inside. This allows plants to produce leaves with a huge range of surface areas without the need for larger cells, which would be 16) __________, the researchers said. Variation in the number of cells arranged vertically cannot be large because light can penetrate only so many layers of cells. On the other hand, the number of cells arranged horizontally in the leaf continues to 17) __________ as leaves expand, regardless of the size of the individual cells.
The new allometric equations were said to be 18) __________toward understanding the design of leaves on a cellular basis, but there is still much to learn before some 19) __________ might be imitated synthetically. In future research, the group will study 20) __________ in an effort to uncover any evolutionary relationships between leaf design and function.
Summarized text about “Secret math of plants” retrieved on 31 October, 2013