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BIOL 322 MIDTERM EXAM 2025 QUESTIONS AND ANSWERS "Describe the surface hypothesis regarding the origin of life. What is wrong with it?" ....ANSWER ...-"- Life originated from a primordial soup containing organic and inorganic molecules, forming the first membrane-enclosed self-replicating cell. - It is criticized because Earth was inhospitable at that time." "Explain the subsurface hypothesis and its significance in the formation of life. 3 main points" - ....ANSWER ...-"- Life formed through interactions between alkaline hot water and cold acidic ocean water - Abundant H2S and H2 as energy sources. - Led to the formation of metal precipitates that acted as catalysts for synthesizing amino acids, sugars, and bases, ultimately resulting in macromolecule formation." "Define the role of RNA in the early stages of life formation. 4 main points" ....ANSWER ...-"- First replicating system - Catalyzed the formation of simple peptides - Binds to small molecules like ATP and amino acids. - Played a crucial role in the synthesis of complex proteins before being replaced by DNA." "How did the big oxygenation event occur and who was responsible for it?" ....ANSWER ...-"- 2.8 billion years ago at the end of the Archaean eon - caused by cyanobacteria. - significantly increased the levels of oxygen in the atmosphere." "What were the key events that led to the formation of the first cell?" ....ANSWER ...-"- formation of amino acids, nucleotides, and sugars - the catalytic …FOR STUDENTS ONLY…©️2025 ALL RIGHTS RESERVED… 1