Week#6

A wonderful connect of PCMB with the colour blue

Connecting The color Blue with ;

PHYSICS: The color blue has shorter wavelengths, 492 – 455 nm, compared to green and red that have wavelengths of 577 – 492 nm and 780 – 622 nm, respectively. Most biological pigments absorb blue light because it provides sufficient energy to raise an orbital electron to an excited state.Due to the rarity of blue pigments, nature often uses a pure physical phenomena to create blue called structural color, the physics of light at the nanoscale. When light hits the cell wall or the exoskeleton of an organism, it interacts with the micro- and nanostructures of their body. Reflection, refraction, interference, diffraction and scattering can become sources of structural colors and can be enhanced by combining these optical phenomena

As an example, the feathers of the common blue jay aren’t really blue, they’re gray. The feathers refract light, appearing blue to the human eye.

The morpho butterfly is one of the most studied insects in understanding structural color. The wings of a morpho butterfly are some of the most beautiful structures in nature, and yet they contain no blue pigment.

Nipam Patel’s lab at UC Berkeley is studying how morpho butterflies form the special structures, the scales that cover their wings while still inside the pupae. Each scale is like a pixel, tiny pieces of tile in a larger mosaic, set in layers of overlapping rows. Ridges on the scale’s surface are a key component that affects how the wing spreads or refracts light, similar to a prism. When light hits the ridges, a phenomenon called constructive interference comes into play, which is essentially when the diffracted light waves are intensified and reflected. The spacing within the ridges, which look like little “Christmas trees”, perfectly reinforces specific wavelengths while canceling out others. This is how the eye perceives that shimmering blue. Scientists are still unsure why, but vertebrates and plants rarely produce blue as a pigment.

CHEMISTRY : The human eye perceives a mixture of all the colors, in the proportions present in sunlight, as white light. Complementary colors, those located across from each other on a color wheel, are also used in color vision. The eye perceives a mixture of two complementary colors, in the proper proportions, as white light. Likewise, when a color is missing from white light, the eye sees its complement. For example, when red photons are absorbed from white light, the eyes see the color green. When violet photons are removed from white light, the eyes see lemon yellow

The blue color of the tetraamminecopper(II) ion

results because this ion absorbs orange and red light, leaving the complementary colors of blue and green

. If white light (ordinary sunlight, for example) passes through tetraamminecopper(II) sulphate solution, some wavelengths in the light are absorbed by the solution. The tetraamminecopper(II) ions in solution absorb light in the red region of the spectrum. The light which passes through the solution and out the other side will have all the colors in it except for the red. We see this mixture of wavelengths as pale blue (cyan). The diagram gives an impression of what happens if you pass white light through a tetraamminecopper(II) sulphate solution.

MATHS:

1. Graphs and Visual Representation: In mathematics, graphs and visual representations are often used to help explain concepts and data. The color blue, along with other colors, is frequently used to differentiate between different elements or data points in graphs, charts, and diagrams. This helps make mathematical information more accessible and understandable.

2. Blue as a Visualization Aid: Blue can be used as a background or highlighting color in mathematical software, presentations, and textbooks to draw attention to important mathematical concepts or equations. It can enhance readability and comprehension by creating visual contrast.

3. Educational Materials: In educational materials for mathematics, including textbooks and online resources, blue is often used for headings, labels, or important information. The use of color, including blue, helps organize content and guide students through mathematical concepts.

4. Geometry and Shapes: In geometry, blue can be used to represent shapes or lines in diagrams and proofs. For example, in Euclidean geometry, blue lines may represent theorems or constructions. In analytical geometry, blue can be used to denote specific regions or geometric objects.

5. Color-Coding: Some math educators and researchers use color-coding to help students understand mathematical concepts. Blue, along with other colors, can be used to categorize or differentiate mathematical elements, making it easier for students to identify and remember them.

While the color blue itself doesn't have inherent mathematical significance, its use in mathematical communication and education can aid in conveying mathematical concepts effectively and enhancing the learning experience.

BIOLOGY :

1. Vision and Perception: Blue is one of the primary colors of visible light, and the human visual system is sensitive to this color. In biology, the study of vision, color perception, and the biology of the eye are essential areas of research. Scientists study how photoreceptor cells, such as cones in the retina, respond to different wavelengths of light, including blue light. Blue light perception plays a role in various biological processes, including circadian rhythms and the regulation of sleep.

2. Animal Attraction and Communication: In the natural world, many species of animals use the color blue as part of their mating rituals and communication strategies. For example, certain birds, insects, and marine animals have vibrant blue colors in their plumage, wings, or body patterns to attract mates or deter predators. The study of these biological adaptations and the role of blue in animal behavior is of interest to biologists and ecologists.

3. Bioluminescence: Blue is a common color in bioluminescent organisms, such as certain species of jellyfish and deep-sea creatures. These organisms produce blue light through chemical reactions involving molecules like luciferase and luciferin. The study of bioluminescence and its biological functions, including predation, camouflage, and attracting prey, is a fascinating area within biology.

4. Marine Biology: Blue is often associated with the color of the sea and oceans. Marine biology is a specialized field that focuses on the study of marine organisms, ecosystems, and the effects of environmental factors on ocean life. Understanding the biology of marine species, their adaptations to blue environments, and the conservation of marine ecosystems is crucial for scientists and researchers in this field.

5. Chromatophores and Pigments: Some animals, such as certain cephalopods (e.g., octopuses and cuttlefish), have specialized cells called chromatophores that allow them to change color, including shades of blue. The biology of chromatophores and the pigments responsible for color change are areas of interest in understanding animal camouflage, communication, and defense mechanisms.

In summary, the color blue has various biological implications, from its role in human vision and perception to its significance in the natural world for signaling, adaptation, and communication among organisms. Biologists often study these aspects as they explore the diverse ways in which the color blue interacts with living organisms and their environments.