Answer:
"Survival of the fittest" is a phrase that originated from Darwinian evolutionary theory as a way of describing the mechanism of natural selection. The biological concept of fitness is defined as reproductive success.
Explanation:
The Darwinian evolutionary theory was created by Charles Darwin.
Darwin published his theory of evolution with compelling evidence in his 1859 book On the Origin of Species, overcoming scientific rejection of earlier concepts of transmutation of species. By the 1870s, the scientific community and a majority of the educated public had accepted evolution as a fact.
 
        
             
        
        
        
Turning amino acids into molecules that can be used in the Krebs cycle takes energy, which means that burning protein for fuel is not as efficient as burning carbohydrates. ... When amino acids are used as an energy source, it reduces the reserves of amino acids that are available for protein synthesis.
        
             
        
        
        
Answer:The based on this information interaction between these two species can best be described as COMPETITION. Correct option is B
Explanation: 
Competition occurs between two species that shares the same requirements ( especially food) for survival.
Both the Western Toad and the Bull Frog has a similar niche because they require the same type of food (beetles, bees, and small aquatic insects) to survive in the environment of Arroyo Seco. Only one of the species will coexist in that environment and it's usually the survival of the fittest.
This explains the competitive exclusion principle proposed by Georgii Gause in 1934.
 
        
             
        
        
        
Answer:
Un nucleótido es el componente básico de los ácidos nucleicos. ... Un nucleótido consiste en una molécula de azúcar (ribosa en el ARN o desoxirribosa en el ADN) unida a un grupo fosfato y una base que contiene nitrógeno. Las bases utilizadas en el ADN son adenina (A), citosina (C), guanina (G) y timina (T).
Explanation:
 
        
             
        
        
        
Sound waves enter the outer ear and pass into the ear canal where the waves cause the eardrum to vibrate.
Hope this helps you.<3