How the pigments that absorb light for photosynthesis contribute to plants' green color

The chlorophyll in plants captures energy in the form of red and blue light

Light-dependent reactions during photosynthesis convert sunlight into chemical energy, stored within the bonds of molecules such as ATP and NADPH. Rather than being absorbed for these reactions, most green light is reflected, causing most plants to appear green.

During the fall, chlorophyll breakdown in leaves produces color changes

With shorter days and less sunlight, the concentration of the green pigment diminishes, revealing yellow and orange pigments. Red leaves result from trapped sugars, producing new pigments called anthocyanins, which weren't present in leaves during the growing season.

Imagining if humans could perform photosynthesis and how it would change our anatomy

Since chloroplasts reflect green light, becoming photosynthetic would give our skin a green appearance. Because photosynthesis has efficiencies of only 5% to 9%, and humans burn 2,000 Calories daily compared to about 200 burned by a tree, becoming photosynthetic would also require us to adopt a less active, sun-filled lifestyle.

Rubisco, the crucial enzyme powering photosynthesis

Photosynthesis is the crucial process by which plants absorb sunlight, take up water, and breathe in carbon dioxide, prompting chemical reactions that result in the byproducts sugar and oxygen. A key enzyme, rubisco, is responsible for it all, but it is inefficient. This video explores the key protein and reveals fascinating facts about oxygen and photosynthesis.

The three categories of photosynthesis, which each help plants survive in different environments

In the vast majority of plants, C3 photosynthesis produces three-carbon intermediate molecules in the Calvin cycle within the cells of leaves. Plants in hot, dry climates use C4 photosynthesis across two types of cells to produce four-carbon molecules before the Calvin cycle. Plants in drought conditions use CAM to store carbon dioxide as an acid at night, minimizing water loss.

Breaking down sunlight and why the sun appears yellow despite emitting green light the most

This peak intensity is produced alongside a spectrum of other colors, which, when combined, make the sun appear white in space. Since Earth's atmosphere scatters bluer and greener wavelengths of light more than red and orange wavelengths, sunlight reaching Earth's surface appears yellow, while the sky appears blue. (Some readers may experience a paywall.)

A look at anoxygenic photosynthetic bacteria, which do not produce oxygen

Rather than using water to produce organic compounds and release oxygen, purple and green sulfur bacteria take up hydrogen sulfide, carbon dioxide, and light to produce water, elemental sulfur, and a carbohydrate. Other organisms can take up various molecules and elements, such as iron, which can replenish the electrons in pigments involved in light-dependent reactions.

When processing light, the brain can perceive colors with no natural wavelength

While some animals are sensitive to many forms of light, humans possess receptors that are sensitive to red, green, and blue wavelengths. These receptors send signals to the brain, which are processed and mixed to produce the array of colors we observe, including magenta, pink, and "supercolors" that lack a corresponding natural wavelength in the visible spectrum.

Learn about photoautotrophs, the photosynthetic organisms at the base of the food web

The sun is the ultimate source of energy for the planet, but consumers along food chains, such as herbivores and carnivores, cannot harness this energy themselves and instead rely on consuming plants and other organisms that capture it to build carbohydrates. Besides plants, photoautotrophs include algae and some bacteria that convert solar energy into chemical energy for the biosphere.

Visualize the purpose of stomata in photosynthesis

These openings on the underside of leaves can be opened and closed by specialized guard cells to regulate the movement of carbon dioxide into and oxygen out of cells, thus impacting the rate of photosynthesis. At night, when the light-dependent reactions in photosynthesis are not possible, the stomata close to prevent the plant from losing water through transpiration.

How artificial photosynthesis can help make plastics and fuels using sunlight

These systems link a molecular light absorber to a catalyst that can synthesize fuels—such as ethanol—and ethylene, a precursor to plastics, in a carbon-neutral manner. Because these byproducts have greater energy concentrations than the carbohydrates produced by photosynthetic organisms, research is ongoing to engineer the necessary catalysts.

Understanding the role of photosynthesis as a sink within the carbon cycle

Photosynthetic organisms are net carbon absorbers, pulling carbon dioxide from the atmosphere and storing it in organic compounds and within soil. Approximately one-third of humanity's carbon emissions are stored by these organisms.

Greenhouse gas concentrations can be measured using spectroscopy

Each type of greenhouse gas absorbs a distinct set of wavelengths of light, which serve as a unique spectral signature. By shining light through an atmospheric sample and measuring the light on the other side, the amount of each gas can be calculated from the amount of missing light.

Water is naturally tinted with a slight blue, but sediments and organics can alter its color

The innate coloration comes from water absorbing red light in the visible spectrum more than green or blue, giving shallow waters in some parts of the Caribbean their turquoise hue. If sand is light, it can be churned up by turbulent water, clouding its appearance. Plankton and other organisms can color water by affecting how the rest of the spectrum is absorbed or reflected.

What is the rarest color in nature?

Plants, animals, or minerals found in nature bear almost every color imaginable. There are two factors that influence what hues you see in the wild: physics and evolution. So, which colors are you least likely to see in the natural world? Victoria Hwang explores one of nature’s rarest spectacles.

Watch students comically portray how plants can detoxify the environment

Through a series of processes that collectively make up phytoremediation, plants can take up pollutants from soil and water through their roots, then break them down, release them as less harmful gases, or store them within their cells. Any plants that sequester heavy metals or other toxins must be removed and managed after the environment is decontaminated.

Glow sticks feed energy released in chemical reactions to fluorescent dyes

When bent, the glass tube inside the stick breaks, releasing hydrogen peroxide into the surrounding solution. The ensuing reaction creates unstable molecules that decompose and release energy, which is then absorbed by molecular dyes that emit light when their excited electrons return to lower energy states.

The history of iconic pigments used in seven famous paintings

While art paints can be bought by the bucket at any craft store today, pigments throughout history have been difficult to come by. Art historian Kelly Grovier traces the fascinating history of pigments that make up hidden layers in masterpieces from Picasso and Hokusai’s Prussian Blue to Vermeer’s shade of red.

Photographer captures glowing flowers in ultraviolet light

Debora Lombardi utilizes ultraviolet light to reveal unseen colors in flowers, re-shaping their natural beauty. Beginning during the lockdown of March 2020, Lombardi's experimentation evolved, culminating in a series recognized by the World Photography Organization. Her work highlights vibrant purples, blues, and yellows, transforming flowers into surreal, otherworldly specimens by exposing them to UV light in her Italy-based studio.

Copper is responsible for turning blonde hair green in swimming pools

Pools use copper sulfate to control algae, which can bind to hair either damaged by the sun or recently bleached. Chlorine, which is often considered to be the culprit, weakens the hair structure to exacerbate the green coloration reaction, rather than causing it.

LEDs emit pure colors, while incandescent bulbs filter white light

Traditional Christmas lights produce softer, less saturated colors by partially blocking the full spectrum of light, resulting in a particularly warm glow by dimming the cooler blue tones. LEDs are designed to emit a single wavelength of light, creating intense colors that are visually unbalanced in multicolor environments.

Plant hormones and growth regulators guide growth stages and responses in plants

Plants naturally produce hormones like auxin and gibberellins, while humans apply synthetic or extracted growth regulators to control plant development. These substances influence processes like flowering, root growth, dormancy, and ripening—even in very small doses.

What do psychedelic plants look like?

Far from the drippy aesthetic often associated with psychedelics, the plants powering naturally occurring psychoactive experiences may not stand out as anything special. This database offers a visual guide to psychoactive plants and fungi. Clicking on the title of a particular plant, such as yerba mate, will bring up a secondary screen with various hyperlinked images, such as the plant itself, related botanical drawings, and molecular structures.

Chromium contaminants in a ruby crystal gave the world's first laser its red color

The red light originates from a long-lasting excited electron state in the element's atomic structure. The brittle gray metal has historically been used in pigment production, the manufacturing of rust-resistant stainless steel, and the creation of durable coatings with long-lasting shine for metals, wood, and leather.

Coral reefs get their colors from zooxanthellae—microorganisms that line corals' digestive tracts and provide them with sugars in exchange for a home within this protective tissue.

Massive blooms of microscopic plankton called dinoflagellates produce the neon blue light seen in glowing tides.

Infrared light is most often associated with thermal radiation and cooking food

Although extensively used in remote controls for electronics, where LED lights send signals wirelessly, infrared cameras allow for night vision and thermography—imaging of heat patterns in the body to non-invasively reveal blood flow for supplementary diagnostics. Infrared radiation also provides heat in toasters, saunas, and other technologies.

Scientists testing how climate change affects plants found, in a years-long simulation study, that poison ivy grew 70% faster with the resulting extra carbon dioxide.

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

When caught in the mouths of cardinal fish, seed shrimp release glowing, bioluminescent chemicals, which alert predators of the cardinal fish, prompting the shrimp's ejection.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

Georgia O'Keeffe's flower paintings are often assumed to be sexual, though the artist claimed she was simply interested in highlighting the beauty of flowers that most people neglect

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

Tattoos remain visible on your skin thanks to immune cells called macrophages

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

The Brothers Grimm were lawyers before they were storytellers, but became interested in fairy tales as they began investigating how rules and customs had been passed down through cultures.

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

After the Boston Tea Party, colonists switched to coffee, which became the main morning drink for revolutionaries.

Ebola species have historically been named after where they were discovered, stigmatizing residents who live there, including Bundibugyo, in Uganda.

The 1987 Nintendo video game 'Stadium Events' isn't known for being particularly fun, but its scarcity has made it a highly sought-after item that has sold for up to $35K at auction.