SCIENCE TEST Flashcards
What are reactants and products of photosynthesis?
Reactants: Water and carbon dioxide
Products: Glucose (sugar) and oxygen
During photosynthesis, light energy (sunlight) combines with the reactants—water and carbon dioxide—to form new products: glucose (sugar) and oxygen.
List the reactants and products of cellular respiration.
Reactians: Glucose (sugar) and oxygen
Products: Carbon dioxide molecules and water molecules
During cellular respiration, the reactants—glucose (sugar) and oxygen combine together to form new products: carbon dioxide molecules and water molecules. Adenosine triphosphate (ATP) is produced as the form of energy that can be used for other cellular processes.
Explain how photosynthesis and cellular respiration have similar reactants and products.
The reactants and products of photosynthesis and cellular respiration are exactly the same, but they are flipped in the reactant and product way. So for example when photosynthesis PRODUCES glucose and oxygen, cellular respiration has these two as its reactants.
Explain the difference between photosynthesis and cellular respiration
Photosynthesis converts carbon dioxide and water into oxygen and glucose. Glucose is used as food by the plant and oxygen is a by-product. Cellular respiration converts oxygen and glucose into water and carbon dioxide. Water and carbon dioxide are by- products and ATP is energy that is transformed from the process.
Apply the 10% rule to an energy pyramid
On average, only about 10 percent of energy stored as biomass in a trophic level is passed from one level to the next. This is known as “the 10 percent rule” and it limits the number of trophic levels an ecosystem can support.
Describe the carbon cycle and human impacts upon it
Burning fossil fuels, changing land use, and using limestone to make concrete all transfer significant quantities of carbon into the atmosphere. As a result, the amount of carbon dioxide in the atmosphere is rapidly rising; it is already greater than at any time in the last 3.6 million years.
Describe the phosphorus cycle and human impacts upon it
Human actions—mining phosphorus (P) and transporting it in fertilizers, animal feeds, agricultural crops, and other products—are altering the global P cycle, causing P to accumulate in some of the world’s soil. Increasing P levels in the soil elevate the potential P runoff to aquatic ecosystems
Humans greatly influence the phosphorus cycle through the release of mined phosphates into ecosystems, especially in the form of fertilizers, but also from detergents and sewage waste.
Describe the nitrogen cycle and human impacts upon it
Ecological Implications of Human Alterations to the Nitrogen Cycle. Many human activities have a significant impact on the nitrogen cycle. Burning fossil fuels, application of nitrogen-based fertilizers, and other activities can dramatically increase the amount of biologically available nitrogen in an ecosystem.
Description of carbon cycle
The carbon cycle is nature’s way of reusing carbon atoms, which travel from the atmosphere into organisms in the Earth and then back into the atmosphere over and over again. Most carbon is stored in rocks and sediments, while the rest is stored in the ocean, atmosphere, and living organisms.
