搜尋結果
2 天前 · Michael Joseph Jackson (August 29, 1958 – June 25, 2009) was an American singer, songwriter, dancer, and philanthropist. Known as the " King of Pop ", he is widely regarded as one of the most significant cultural figures of the 20th century. During his four-decade career, his contributions to music, dance, and fashion, along with his ...
4 天前 · Photosynthesis ( / ˌfoʊtəˈsɪnθəsɪs / FOH-tə-SINTH-ə-sis) [1] is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their activities.
4 天前 · t. e. The viscosity of a fluid is a measure of its resistance to deformation at a given rate. [1] For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. [2] Viscosity is defined scientifically as a force multiplied by a time divided by an area.
2 天前 · Dymaxion map of the world with the 30 largest countries and territories by area This is a list of the world's countries and their dependencies by land, water, and total area, ranked by total area.Entries in this list include, but are not limited to, those in the ISO 3166-1 standard, which includes sovereign states and dependent territories.
1 天前 · The BBC is a state owned public broadcasting company and operates under a royal charter.The charter is the constitutional basis for the BBC, and sets out the BBC's Object, Mission and Public Purposes. It emphasises public service, (limited) editorial independence, prohibits advertising on domestic services and proclaims the BBC is to "seek to avoid adverse impacts on competition which are not ...
4 天前 · A protein is a polyamide. Secondary structure: regularly repeating local structures stabilized by hydrogen bonds. The most common examples are the α-helix, β-sheet and turns. Because secondary structures are local, many regions of different secondary structure can be present in the same protein molecule.
1 天前 · The foundations of a Russian national state were laid in the late 15th century during the reign of Ivan III. By the early 16th century, all of the semi-independent and petty princedoms in Russia had been unified with Moscow. During the reign of Ivan IV, the khanates of Kazan and Astrakhan were conquered by Russia in the mid-16th century, leading to the development of an increasingly ...
