Uracil and cytosine are both nitrogenous bases found in RNA. Both uracil and cytosine are polar molecules due to the presence of electronegative atoms (oxygen and nitrogen) in their chemical structure. This polarity allows them to form hydrogen bonds with other nucleotides, contributing to the stability of the RNA molecule. **

Uracil is not used in DNA instead of adenine. In DNA, adenine pairs with thymine, while in RNA, adenine pairs with uracil. This difference is due to the fact that uracil is more easily formed from cytosine through a simple deamination reaction, making it a more efficient choice for RNA. Additionally, the presence of thymine in DNA provides an extra layer of protection against mutations, as thymine is less prone to spontaneous deamination compared to uracil. **

Thymine is replaced by uracil in RNA because uracil can form a base pair with adenine, just like thymine does in DNA. This allows for the same complementary base pairing rules to apply in RNA as in DNA, facilitating the accurate transcription of genetic information from DNA to RNA. Additionally, uracil is more easily synthesized than thymine, making it a more efficient choice for RNA molecules. **

RNA contains uracil instead of thymine because uracil is more suitable for RNA's functions. Uracil is able to base-pair with adenine, just like thymine does in DNA, allowing for proper complementary base pairing during transcription and translation processes. Additionally, uracil is more easily synthesized from the precursor molecule in RNA synthesis, making it a more efficient choice for RNA. Thymine, on the other hand, is more stable and less prone to mutations, which is important for the long-term storage of genetic information in DNA. **

The caricature of the summit conference in Helsinki shows the leaders of the United States and Russia, Donald Trump and Vladimir Putin, sitting at a table with Trump holding a puppet string attached to Putin. This caricature is a satirical representation of the perception that Trump is under the control or influence of Putin, suggesting that Putin is pulling the strings and manipulating Trump. The image reflects the controversy and speculation surrounding the relationship between the two leaders and the potential influence of Russia on the United States. **

A symposium is a formal gathering or meeting where experts in a particular field come together to discuss and exchange ideas on a specific topic. It is often organized as a series of presentations, panel discussions, and Q&A sessions, allowing participants to share their knowledge and insights with each other. Symposia are commonly held in academic and professional settings, providing a platform for networking, collaboration, and learning within a specific discipline or industry. **

"Der Kongress tanzt" is a German phrase that translates to "The Congress Dances" in English. The phrase originated from the Congress of Vienna in 1814-1815, where European diplomats and leaders gathered to reorganize Europe after the Napoleonic Wars. The phrase is a metaphor for the diplomatic and political maneuvering that took place during the Congress, likening it to a dance where participants carefully navigated their relationships and alliances. It reflects the complex and intricate nature of international diplomacy and negotiations during this historic event. **

A convention is a formal agreement or a set of accepted norms and practices that govern behavior in a particular context or industry. It is a customary way of doing things that is widely recognized and followed by a group of people. Conventions help to establish consistency, order, and predictability in social interactions or professional settings. They can vary across different cultures, societies, or fields of study. **