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be blue one day and stormy the next? Why do heavy objects tend to fall downwards when dropped? How are birds able to fly (and why can’t I do the same?)? Human beings have long been curious about the world in which we live, striving to identify connections among the phenomenons we witness and to understand how it all works. The field of science has developed over many centuries as a way of studying and understanding the world, beginning with the primitive stage of simply noting important regularities in nature and continuing through the rise of modern science. The modern-day sciences cover a vast range of fields, including biology, chemistry, meteorology, astronomy, physics, and much more.</div> </div> <div class="text-hr text-hr-right border-navy label mt-30 ls-lg">Browse Subcategories</div> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 mt-20 category-snap-slider"> <div class="slider-container js-slider-container overflow-hidden d-flex font-14 overflow-hidden text-nowrap mx-5"> <a href="/browse/Astronomy" class="link-white mr-20 mr-sm-30">Astronomy</a> <a href="/browse/Biology" class="link-white mr-20 mr-sm-30">Biology</a> <a href="/browse/Birds-Reptiles-Vertebrates" class="link-white mr-20 mr-sm-30">Birds, Reptiles & Other Vertebrates</a> <a href="/browse/Bugs-Mollusks-Invertebrates" class="link-white mr-20 mr-sm-30">Bugs, Mollusks & Other Invertebrates</a> <a href="/browse/Chemistry" class="link-white mr-20 mr-sm-30">Chemistry</a> <a href="/browse/Earth-Science-Geology-Fossils" class="link-white mr-20 mr-sm-30">Earth Science, Geologic Time & Fossils</a> <a href="/browse/Environment" class="link-white mr-20 mr-sm-30">Environment</a> <a href="/browse/Mammals" class="link-white mr-20 mr-sm-30">Mammals</a> <a href="/browse/Mathematics" class="link-white mr-20 mr-sm-30">Mathematics</a> <a href="/browse/Plants" class="link-white mr-20 mr-sm-30">Plants</a> <a href="/browse/Physics" class="link-white ">Physics</a> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> </div> <div class="container"> <h2 class="label my-30 text-center">Featured content, April 02, 2025</h2> <div class="qa-pinboard-items js-pinboard grid gy-20"> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/story/how-do-you-rewild-an-environment" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/68/231268-131-72170325/restored-wetland-area-Starke-County-Indiana-2021.jpg?w=400&h=225&c=crop" alt="Water sits in a macro at a a restored wetland area in Starke County, Indiana May 25, 2021. The area is enrolled in the NRCS' Wetland Reserve Easement Program. The easement includes 200.6 acres of former cropland that were restored to create wetland, prairie and forest habitat for wildlife. The purpose of the macros is to provide habit and food to a variety of animals including migrating waterfowl, while returning the landscape to its natural appearance prior to the installation of drainage for agriculture and urban development." class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/story/how-do-you-rewild-an-environment" class="font-weight-bold font-16 lh-sm">How Do You Rewild an Environment?</a> <div class="font-serif mt-10 font-14"> The removal of invasive species and the reintroduction of native species make up the bulk of a rewilding project. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/story/why-is-the-ocean-salty" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/65/161665-131-5A36B507/Waves-North-Shore-Oahu-Hawaiian-Islands.jpg?w=400&h=225&c=crop" alt="Waves, North Shore of Oahu, Hawaiian Islands, United States." class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/story/why-is-the-ocean-salty" class="font-weight-bold font-16 lh-sm">Why Is the Ocean Salty?</a> <div class="font-serif mt-10 font-14"> Why is seawater salty? </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/list/8-birds-that-cant-fly" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/22/7122-131-7F298ADF/cassowary.jpg?w=400&h=225&c=crop" alt="Common, or southern, cassowary (Casuarius casuarius)." class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/list/8-birds-that-cant-fly" class="font-weight-bold font-16 lh-sm">8 Birds That Can’t Fly</a> <div class="font-serif mt-10 font-14"> What good is flight, anyway? </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/story/exploring-7-of-earths-great-mountain-ranges" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/72/11472-131-EE904FD3/Bear-Hat-Mountain-Hidden-Lake-Montana-Glacier.jpg?w=400&h=225&c=crop" alt="Bear Hat Mountain above Hidden Lake on a crest of the Continental Divide in Glacier National Park, Montana" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/story/exploring-7-of-earths-great-mountain-ranges" class="font-weight-bold font-16 lh-sm">Exploring 7 of Earth’s Great Mountain Ranges</a> <div class="font-serif mt-10 font-14"> Get to know the plants and animals of major mountain ranges around the world. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/mathematics" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/54/2354-050-B47B3735/Babylonian-tablet.jpg?w=400&h=225&c=crop" alt="Babylonian mathematical tablet" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/mathematics" class="font-weight-bold font-16 lh-sm">mathematics</a> <div class="font-serif mt-10 font-14"> Mathematics, the science of structure, order, and relation that has evolved from elemental practices of counting, measuring,... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/topic/philosophy-of-science" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/84/87984-050-7C5547FE/Detail-Roman-copy-portrait-bust-Aristotle-Greek.jpg?w=400&h=225&c=crop" alt="Aristotle" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/topic/philosophy-of-science" class="font-weight-bold font-16 lh-sm">philosophy of science</a> <div class="font-serif mt-10 font-14"> Philosophy of science, the study, from a philosophical perspective, of the elements of scientific inquiry. This article discusses... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/control-group" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-134/images/shared/default3.png?v=3.134.26" class="default col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/control-group" class="font-weight-bold font-16 lh-sm">control group</a> <div class="font-serif mt-10 font-14"> Control group, the standard to which comparisons are made in an experiment. Many experiments are designed to include a control... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex js-pin col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="https://www.britannica.com/science/science" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/42/154842-138-D063918E/Kara-Rogers-difference-Encyclopaedia-Britannica-theory-hypothesis.jpg?w=400&h=225&c=crop" alt="Understanding scientific hypotheses, theories, and models" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="https://www.britannica.com/science/science" class="font-weight-bold font-16 lh-sm">science</a> <div class="font-serif mt-10 font-14"> Science, any system of knowledge that is concerned with the physical world and its phenomena and that entails unbiased observations... </div> </div> </div> </div> </div> </div> <div class="qa-quizzes"> <h2 class="h3 mt-30 mb-20 font-weight-bold">Science Quizzes</h2> <div class="m-n10 "> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 card-snap-slider col-100"> <div class="slider-container js-slider-container overflow-hidden d-flex col-100"> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/water-and-its-varying-forms" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/02/157502-131-7C5D3A67/water-glass-background.jpg?w=400&h=225&c=crop" alt="water glass on white background. (drink; clear; clean water; liquid)" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/water-and-its-varying-forms" class="font-weight-bold font-16 lh-sm">Water and its Varying Forms</a> <div class="font-serif mt-10 font-14"> Even though water exists in three states, there is only one correct answer to the questions in this quiz. Dive in and test... </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 "> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/energy-fossil-fuels" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/12/156712-131-8E29225D/transmission-lines-electricity-countryside-power-plants-homes.jpg?w=400&h=225&c=crop" alt="Electric power lines against sunset (grid, power, wires, electrical, electricity)" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/energy-fossil-fuels" class="font-weight-bold font-16 lh-sm">Energy & Fossil Fuels</a> <div class="font-serif mt-10 font-14"> From fossil fuels and solar power to Thomas Edison and Nicola Tesla’s electric marvels, the world runs on energy. 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Humankind's fascination with the world beyond Earth has led to many landmark moments in history, as when space exploration took a giant step forward with the advent of technology that allowed humans to successfully travel to the Moon and to build spacecraft capable of exploring the rest of the solar system and beyond.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/biography/Neil-Armstrong">Neil Armstrong</a> <div class="font-serif">American astronaut</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/star-astronomy">star</a> <div class="font-serif">astronomy</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/biography/Valentina-Tereshkova">Valentina Tereshkova</a> <div class="font-serif">Soviet cosmonaut</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Biology"> <img loading="lazy" src="https://cdn.britannica.com/mendel/resources/encyclopedia-placeholder.jpg?w=400&h=225&c=crop" alt="subcategory placeholder" class="col-100 mb-15" /> </a> <a href="/browse/Biology" class="font-weight-bold font-16">Biology</a> <div class="font-serif mt-10 line-clamp clamp-3">How do plants feed themselves? How did dogs evolve from wolves? What good is the appendix in humans, anyway? Such questions fall within the domain of biology, which seeks to understand living organisms and their vital processes (although the jury’s still out on what our appendixes are for). Biology’s diverse fields include botany, ecology, evolution, genetics, medicine, physiology, and zoology.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/marine-biology">marine biology</a> <div class="font-serif"></div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/biological-development">biological development</a> <div class="font-serif"></div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/taxonomy">taxonomy</a> <div class="font-serif">biology</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Birds-Reptiles-Vertebrates"> <img loading="lazy" src="https://cdn.britannica.com/58/26558-004-E2C978A1/Salamander.jpg?w=400&h=225&c=crop" alt="banded fire salamander (Salamandra terrestris)" class="col-100 mb-20" /> </a> <a href="/browse/Birds-Reptiles-Vertebrates" class="font-weight-bold font-16">Birds, Reptiles & Other Vertebrates</a> <div class="font-serif mt-10 line-clamp clamp-3">Although it can be hard to imagine that a peacock and a crocodile have much of anything in common, these animals are actually descendants of the same prehistoric vertebrates. Birds are thought to have descended from carnivorous dinosaurs that began growing feathers by the Late Jurassic Period; thus, birds are technically one lineage of reptiles. This evolutionary link highlights the way in which seemingly incongruous creatures can, in fact, share a common ancestor (though that doesn't mean that we should expect waterfowl and crocodiles to become friends anytime soon).</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/amphibian">amphibian</a> <div class="font-serif">animal</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/chondrichthian">chondrichthyan</a> <div class="font-serif">fish class</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/fish">fish</a> <div class="font-serif">animal</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Bugs-Mollusks-Invertebrates"> <img loading="lazy" src="https://cdn.britannica.com/03/143903-050-DD38BCBE/scanning-electron-micrograph-soybean-cyst-nematode-egg.jpg?w=400&h=225&c=crop" alt="microfauna" class="col-100 mb-20" /> </a> <a href="/browse/Bugs-Mollusks-Invertebrates" class="font-weight-bold font-16">Bugs, Mollusks & Other Invertebrates</a> <div class="font-serif mt-10 line-clamp clamp-3"> Yet, in addition to being critically important—because they naturally recycle decaying matter—in maintaining balance within the food chain, bugs can also be fascinating creatures, whether in regard to the water strider's ability to run across the surface of water or the assassin bugs' varied and creative means of catching and killing their prey. Mollusks, another group of invertebrates, get less of a bad rap. Their ranks include nearly 100,000 described species of soft-bodied animals that are usually wholly or partly enclosed in a calcium carbonate shell; examples include snails, clams, oysters, squids, and octopuses.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/mollusk">mollusk</a> <div class="font-serif">animal phylum</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/worm">worm</a> <div class="font-serif">animal</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/tapeworm">tapeworm</a> <div class="font-serif">flatworm</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Chemistry"> <img loading="lazy" src="https://cdn.britannica.com/40/7440-004-07959002/cycle.jpg?w=400&h=225&c=crop" alt="geochemical cycle" class="col-100 mb-20" /> </a> <a href="/browse/Chemistry" class="font-weight-bold font-16">Chemistry</a> <div class="font-serif mt-10 line-clamp clamp-3">How do you use raw plant materials to manufacture a best-selling perfume? How do you engineer household products that are compliant with environmentally-oriented guidelines? The answers to these questions require an understanding of the laws of chemistry, the science that deals with the properties, composition, and structure of elements and compounds, as well as the transformations that such substances undergo and the energy that is released or absorbed during those processes. Chemistry is also concerned with the utilization of natural substances and the creation of artificial ones. Over time, more than 8,000,000 different chemical substances, both natural and artificial, have been characterized and produced. Chemistry's vast scope comprises organic, inorganic, physical, analytical, and industrial chemistry, along with biochemistry, environmental chemistry, medicinal chemistry, and much more. Through the dedicated efforts of people such as Robert Boyle, Dmitri Mendeleev, John Dalton, Marie Curie, and Rosalind Franklin, the field of chemistry has led to exciting innovations as well as crucial advances in our understanding of how the world functions, starting with the miniscule and unassuming atom.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/chemical-element">chemical element</a> <div class="font-serif"></div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/biochemistry">biochemistry</a> <div class="font-serif">science</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/principles-of-physical-science">principles of physical science</a> <div class="font-serif"></div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Earth-Science-Geology-Fossils"> <img loading="lazy" src="https://cdn.britannica.com/57/143857-050-EAA84535/Neuropteris-ovata-Hoffmann-seed-fern-Ohio.jpg?w=400&h=225&c=crop" alt="seed fern" class="col-100 mb-20" /> </a> <a href="/browse/Earth-Science-Geology-Fossils" class="font-weight-bold font-16">Earth Science, Geologic Time & Fossils</a> <div class="font-serif mt-10 line-clamp clamp-3">Planet Earth has billions of years of history, from the time when it was an inhospitable ball of hot magma to when its surface stabilized into a variety of diverse zones capable of supporting many life-forms. Many are the species that lived through the various geologic eras and left a trace of their existence in the fossils that we study today. But Earth is never done settling, as we can see from the earthquakes, tsunamis, volcanic eruptions, and other phenomena manifested in Earth’s crust, oceans, and atmosphere.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/Keeling-Curve">Keeling Curve</a> <div class="font-serif">atmospheric science</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/oceanography">oceanography</a> <div class="font-serif">science</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/geology">geology</a> <div class="font-serif">science</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Environment"> <img loading="lazy" src="https://cdn.britannica.com/09/102009-050-81C6D817/Earths-hot-spots-of-biodiversity.jpg?w=400&h=225&c=crop" alt="terrestrial hot spots of biodiversity" class="col-100 mb-20" /> </a> <a href="/browse/Environment" class="font-weight-bold font-16">Environment</a> <div class="font-serif mt-10 line-clamp clamp-3">Biological diversity is key to a healthy ecosystem, whether it’s a small biological community or the global biosphere. Ecology, which studies the relationships between organisms and their environment, is an invaluable science that helps us understand what allows an ecological community to thrive.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/hydrosphere">hydrosphere</a> <div class="font-serif">Earth science</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/environment">environment</a> <div class="font-serif">biology</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/recycling">recycling</a> <div class="font-serif"></div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Mammals"> <img loading="lazy" src="https://cdn.britannica.com/03/155303-050-E2B63186/platypus-duckbill-waterways-Australia.jpg?w=400&h=225&c=crop" alt="platypus" class="col-100 mb-20" /> </a> <a href="/browse/Mammals" class="font-weight-bold font-16">Mammals</a> <div class="font-serif mt-10 line-clamp clamp-3">Mammals are distinguished by their ability to produce milk. The class Mammalia boasts tremendous diversity in form and habit, and different types of mammals can be wildly different from one another in physical appearance. Living kinds of mammals range in size from a bat weighing less than a gram to the largest animal that has ever lived, the blue whale, which reaches a length or more than 30 metres (100 feet) and a weight of 180 metric tons (nearly 200 short [U.S.] tons).</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/llama">llama</a> <div class="font-serif">mammal</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/blesmol">blesmol</a> <div class="font-serif">rodent</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/animal/wallaby">wallaby</a> <div class="font-serif">marsupial</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Mathematics"> <img loading="lazy" src="https://cdn.britannica.com/mendel/resources/encyclopedia-placeholder.jpg?w=400&h=225&c=crop" alt="subcategory placeholder" class="col-100 mb-15" /> </a> <a href="/browse/Mathematics" class="font-weight-bold font-16">Mathematics</a> <div class="font-serif mt-10 line-clamp clamp-3">Mathematics is a science of structure, order, and relation that deals with logical reasoning and quantitative calculation. The history of mathematics can be traced back to ancient Mesopotamia; ancient clay tablets have proven that the level of mathematical competence was already high as early as roughly the 18th century BCE. Over the centuries, mathematics has evolved from elemental practices of counting, measuring, and describing the shapes of objects into a crucial adjunct to the physical sciences and technology.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/probability-theory">probability theory</a> <div class="font-serif">mathematics</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/function-mathematics">function</a> <div class="font-serif">mathematics</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/science/calculus-mathematics">calculus</a> <div class="font-serif">mathematics</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Plants"> <img loading="lazy" src="https://cdn.britannica.com/66/166066-050-7EF755F4/flower-Rafflesia-arnoldii-plant-world-endoparasite-host.jpg?w=400&h=225&c=crop" alt="Rafflesia flower" class="col-100 mb-20" /> </a> <a href="/browse/Plants" class="font-weight-bold font-16">Plants</a> <div class="font-serif mt-10 line-clamp clamp-3">Life on Earth owes much to plants. The vast majority of plants carry out photosynthesis to transform light energy into chemical energy, which is the way that virtually all energy in the biosphere becomes available to living things (including us humans). Plants occupy the base of Earth's food webs and are consumed directly or indirectly by all higher life-forms, thereby functioning as the major source of food for humans and other animals. Plants' photosynthetic activity also produces the air that we breathe: almost all the oxygen in the atmosphere is due to the process of photosynthesis. Still not convinced about the merits of plants? Consider the fact that many plants not only serve up crucial nutrients and breathable air but also look good doing it. Many plants are admired for their striking aesthetic qualities, and flowers such as tulips, lilies, sunflowers, and daisies beautify fields, gardens, windowsills, and bouquets the world over. Plants are also a primary source of consumer goods, such as building materials, textile fibers, and pharmaceuticals.</div> <div class="label mt-20">Articles</div> <ul class="list-unstyled"> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/plant/coast-redwood">coast redwood</a> <div class="font-serif">tree</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/plant/Wollemi-pine">Wollemi pine</a> <div class="font-serif">tree</div> </li> <li class="mt-20"> <a class="font-weight-bold" href="https://www.britannica.com/plant/Solanales">Solanales</a> <div class="font-serif">plant order</div> </li> </ul> </div> <div class="col-100 col-sm-33 col-md-25"> <a href="/browse/Physics"> <img loading="lazy" src="https://cdn.britannica.com/34/1534-004-5BBDA0CA/diagram-flotation-separation-cell.jpg?w=400&h=225&c=crop" alt="Schematic diagram of a flotation separation cell." class="col-100 mb-20" /> </a> <a href="/browse/Physics" class="font-weight-bold font-16">Physics</a> <div class="font-serif mt-10 line-clamp clamp-3">What’s the matter? Matter is the material substance that constitutes our whole observable universe, and it is the subject of study of physics. Physics, the basic physical science, studies objects ranging from the very small (using quantum mechanics) to the entire universe (using general relativity). 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