Cells and Energy

colored SEM; magnification 1000What makes these cellsso important to manyother organisms?These diatoms are single-celledalgae that use the process ofphotosynthesis to store chemicalenergy in sugars. Animals eat photosyntheticorganisms such as plantsand algae to get this chemical energy.Photosynthetic organisms also producethe oxygen that is required to releasemuch of the chemical energy in sugars.ConnectingCONCEPTSEcology Microscopicdiatoms are absolutelynecessary for the survivalof other marine organisms,including the humpbackwhale. Why? Diatoms areeaten by small, shrimplikeanimals called krill. In turn,humpbacks and severalother species of whales feedmainly on krill. In fact, a bluewhale’s stomach can holdmore than a ton of krill.Chapter 4: Cells and Energy 99