<p>Captured in a microscope photograph submitted to National Geographic's <a href="http://ngm.nationalgeographic.com/myshot/">My Shot</a> photo community by U.K.-based Greg Parker, two strands of the snaking <em>Spirogyra</em> algae sexually reproduce. So-called conjugation tubes link the strands' cells, allowing them to exchange genetic information.</p> <p>Often seen floating in thin strands on freshwater streams and ponds, <em>Spirogyra</em> cells are filled with chloroplasts—packets of chlorophyll that allow the plants to generate energy via photosynthesis—whose spiraling shapes give the genus its name.</p> <p>(Related <a href="http://news.nationalgeographic.com/news/2011/07/pictures/110725-algae-china-beaches-qingdao-swimming-science-environment-world/">pictures: "Thick Green Algae Chokes Beach-Swimmers Dive In."</a>)</p> <p><strong>Why We Love It</strong></p> <p>"Water bottles? Art? A view into the microscopic world that surrounds us is at once alien and familiar."<em>—Sarah Polger, senior photo editor</em></p> <p>"These slimy algal cells are quite beautiful under the right lighting (and magnification)."<em>—Chris Combs, news photo editor</em></p>