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Anning, depicted with her dog. Mary Anning (21 May 1799 – 9 March 1847) was an English fossil collector and palaeontologist. She made discoveries of Jurassic marine fossil beds in the cliffs along the English Channel at Lyme Regis, which changed the scientific thinking about prehistoric life and the history of the Earth.
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. [9] It is mainly used as a eugeroic ( wakefulness promoter) or as a mild cognitive enhancer to increase alertness and attentional performance. [10] [11] Caffeine acts by blocking binding of adenosine to the adenosine A 1 receptor, which enhances release of the ...
- C₈H₁₀N₄O₂
- 45 minutes–1 hour
UNICEF (/ˈjuːniˌsɛf/ YOO-nee-SEF), originally called the United Nations International Children's Emergency Fund in full, now officially United Nations Children's Fund,[a] is an agency of the United Nations responsible for providing humanitarian and developmental aid to children worldwide.[3][4] The organization is one of the most widely ...
Synonyms. Sus hydrochaeris Linnaeus, 1766. The capybara [a] or greater capybara ( Hydrochoerus hydrochaeris) is a giant cavy rodent native to South America. It is the largest living rodent [2] and a member of the genus Hydrochoerus. The only other extant member is the lesser capybara ( Hydrochoerus isthmius ).
The United Nations Educational, Scientific and Cultural Organization ( UNESCO) [a] is a specialized agency of the United Nations (UN) with the aim of promoting world peace and security through international cooperation in education, arts, sciences and culture. [2] [3] It has 194 member states and 12 associate members, [4] as well as partners in ...
The number π (/paɪ/; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although ...
Adrenochrome is a chemical compound produced by the oxidation of adrenaline (epinephrine). It was the subject of limited research from the 1950s through to the 1970s as a potential cause of schizophrenia. While it has no current medical application, the semicarbazide derivative, carbazochrome, is a hemostatic medication. Despite this compound ...
