Answer:
Without naturally occurring greenhouse gases, Earth's average temperaturewould be near 0°F (or-18°C) instead of the much warmer 59°F (15°C). The concentration of greenhouse gases, especially carbon dioxide and methane, has fluctuated naturallyover geological time scales.
Answer:
B. A small fraction of the energy is transferred to higher trophic levels, majority stays in the lower trophic levels
Explanation:
Energy transfer between trophic levels is insufficient. When an organism is eaten by another organism, not all of the biomass of prey forms the biomass of the predator. Majority of the energy is released into environment during cellular respiration. Some of the matter also remains undigested and is not used by the predator. Thus, only 10% of energy available at one level is transferred to the next level. So when we keep on moving up in a food chain, energy available keeps on decreasing.
That would be catalysts.
Catalysts accelerate (speed up) chemical reactions without damaging itself. They do this by decreasing the activation energy of a chemical reaction.
Enzymes are a type of catalysts.
B. It results in narrowing of arteries which slows the blood flow