Current high levels of fossil fuel use, including coal-burning power plants and gasoline-powered automobiles, have helped contribute to the high concentrations of sulfur trioxide, SO₃, found in the atmosphere. When sulfur trioxide and water interact, they can undergo the following chemical reaction to produce sulfuric acid, which is the main contributor to acid rain worldwide: 

Acid rain showers are particularly common near coal-burning power plants and large cities. These showers are responsible for significant economic damage to sidewalks, roads, and buildings. Scientists interested in studying the effects of acid rain often use basic substances like calcium carbonate, the main component of limestone buildings, and expose them to varying volumes of acid rain to determine what volume of acid rain is necessary to begin to erode a building. A sample graph of one scientist’s experiment is replicated below:

Measuring acid and base levels is commonly done with a scale called pH, which uses the concentration of hydrogen ions to determine the acidity. Hydrogen ions are in a balance with hydroxide ions to give a scale with a range from 0 to 14. Values equal to or between 0 and 6.9 represent the acidic range where hydrogen ions predominate and values equal to or ranging from 7.1 and 14 represent the basic range where hydroxide ions predominate. Thus, the more hydrogen ions present, the more acidic the solution.

Scientists can tell when a titration (pH) experiment passes a certain pH using compounds called indicators. Indicators are usually colorless at pH levels below that of their specified color change. A table of indicators used by the above scientists and the pH at which they change colors is presented below. 

According to the passage, why are acid rain showers more common near cities?

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

Prokaryotes would be expected to undergo which of the following processes based on the passage?

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

According to the passage, which process(es) require membrane-bound organelles to occur?

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

In a fasting state, where a person had not eaten recently, the concentration of glucose in the blood is expected to be which of the following?

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

A newly discovered species does not have the enzymes necessary to run the Krebs Cycle. What effect would this have on the level of glucose found in this organism’s blood compared to an organism that could run the Krebs Cycle?

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

Which macronutrient may be used to form glucose through the process of gluconeogenesis?

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

In a person who has not eaten for an extended period of time, which process is most likely providing necessary ATP for bodily functions?

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

In a person who has recently eaten, which process is least likely to be occurring? 

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

An 8-carbon free fatty acid could be expected to produce how many FADH₂? 

In contrast to prokaryotes, eukaryotes have membrane-bound organelles that allow their cell(s) to compartmentalize different cellular functions. These different functions, which occur only within membrane-bound organelles, include the synthesis and breakdown of different macronutrients fatty acids and proteins. Other processes like glycolysis (the breakdown of carbohydrates) and nucleic acid breakdown can occur outside membrane-bound organelles. Synthesizing different macronutrients is known as anabolism, while breaking down these same nutrients into Adenosine Tri-Phosphate (ATP) is called catabolism.

Macronutrient anabolism and catabolism are balanced by the supply of available energy. In the fed state, where a high concentration of sugar is dissolved in your blood stream, the body prefers to use glucose as its energy source through a pathway called glycolysis. When the supply of glucose in the blood runs low, however, the liver is able to synthesize new glucose in a process called gluconeogenesis. In gluconeogenesis, oxaloacetate, the product of another cycle called the Krebs Cycle is used as the starting point to run glycolysis in reverse, making a new glucose molecule. When these precursors needed to initiate gluconeogenesis run low, the body then turns to the catabolism of proteins and free fatty acids.

Proteins, composed of strands of amino acids, are broken down to generate ATP and oxaloacetate. People who have not eaten for an extended period of time experience low muscle mass due to catabolism of skeletal muscle proteins. Only after available protein is broken down does beta oxidation of free fatty acids begin.

Beta oxidation uses free fatty acids floating in the blood to generate the greatest amount of ATP per gram of starting material of any of the macronutrients. Carried out by enzymes called lipases, beta oxidation splits a long fatty acid chain into two carbon units called acetyl-CoA. Per acetyl-CoA that enters the Krebs Cycle, three NADH and one FADH₂ are produced that enter the Electron Transport Chain to drive ATP production. 1 NADH molecule can generate 3 ATP, while 1 FADH₂ molecule can generate 2 ATP. Lipases continue to cleave acetyl-COA units off the parent lipid chain until it either produces its last acetyl-CoA molecule or ends in a 3 carbon molecule called propyl-CoA. Propyl-CoA can further undergo catabolism to yield one final acetyl-CoA molecule.

How many ATP is the body able to produce from a 4-carbon free fatty acid?