Antibiotics are, initially, molecules naturally synthesized by microorganisms to fight against bacteria competing with their environment. This created a pressure of selection on the bacterial populations, leading to the appearance of resistant strains. In fact, when an antibiotic is used, only bacteria with defense systems against this molecule survive (and reproduce).
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One group of reptiles, characterized by the fossil Archaeopteryx, led to the evolution of birds. The correct answer is birds
Producers: living things that make their own food through a process called photosynthesis
Autotrophs: an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide.
Heterotrophs: an organism deriving its nutritional requirements from complex organic substances.
Photo autotrophs: organisms that carry out photosynthesis. Using energy from sunlight, carbon dioxide and water are converted into organic materials to be used in cellular functions such as biosynthesis and respiration.