Cellular Respiration Quiz: Test

The energy of the electrons passing along the electron transport chain is used to make ATP. ATP (adenosine triphosphate) is the primary energy currency of cells. It is produced during cellular respiration through a process called oxidative phosphorylation, which occurs in the inner mitochondrial membrane. As electrons are transferred along the electron transport chain, their energy is used to pump protons across the membrane, creating a proton gradient. This gradient is then used by ATP synthase to produce ATP from ADP and inorganic phosphate. Therefore, ATP is the correct answer as it is the main product of the electron transport chain.

The correct sequence of events in aerobic cellular respiration is glycolysis, followed by the Krebs cycle, and then the electron transport chain. Glycolysis is the initial step in which glucose is broken down into pyruvate. The pyruvate then enters the Krebs cycle, where it undergoes further reactions to produce energy-rich molecules. Finally, these energy-rich molecules are used in the electron transport chain to generate ATP, the main energy currency of the cell. Therefore, the correct answer is glycolysis > Krebs cycle > electron transport chain.

The process shown in the equation above is cellular respiration, which is the process by which cells convert glucose and oxygen into carbon dioxide, water, and ATP (energy). Cellular respiration occurs in the mitochondria of a cell, where the majority of ATP production takes place. The equation represents the overall reaction of cellular respiration, which starts in the cytoplasm with the breakdown of glucose and ends in the mitochondria with the production of ATP. Therefore, the correct answer is mitochondria.

Cellular respiration is the process by which cells break down glucose and convert it into energy. Unlike photosynthesis, which only occurs in plant cells, cellular respiration occurs in all eukaryotic cells. Eukaryotic cells are a type of cell that have a nucleus and other membrane-bound organelles. This means that cellular respiration can occur in both animal and plant cells, as well as in other eukaryotic organisms. Therefore, the correct answer is "all eukaryotic cells".

NADH and FADH2 are molecules that carry high-energy electrons to the electron transport chain. These molecules are produced during the Krebs cycle (also known as the citric acid cycle) when acetyl-CoA is oxidized. ATP and ADP are not directly involved in passing high-energy electrons into the electron transport chain.

The Krebs cycle starts with pyruvic acid (pyruvate) and yields carbon dioxide. This is because pyruvate is converted into acetyl-CoA, which enters the Krebs cycle. During the cycle, acetyl-CoA is further broken down and carbon dioxide is released as a byproduct. This process produces energy in the form of ATP and also generates NADH and FADH2, which are used in the electron transport chain to produce more ATP.

Glycolysis is the process by which glucose is broken down into pyruvic acid (pyruvate) in the cytoplasm of cells. This process occurs in both aerobic and anaerobic conditions. In aerobic conditions, pyruvate is further metabolized in the mitochondria to produce more ATP through the Krebs cycle and oxidative phosphorylation. However, glycolysis itself does not require oxygen and can occur in the absence of oxygen. Therefore, the statement "Glucose is broken down into pyruvic acid (pyruvate)" is true.

The Krebs cycle, also known as the citric acid cycle, is a series of chemical reactions that occur in the matrix of the mitochondria. The matrix is the innermost compartment of the mitochondria, surrounded by the inner membrane. Therefore, the correct answer is 4 only (matrix).

Pathway C, which produces 36 ATP, is known as aerobic respiration and occurs in the presence of oxygen. This is because the final step of aerobic respiration involves the Krebs cycle, which produces carbon dioxide and water. Pathway A, on the other hand, is known as anaerobic respiration and occurs in the absence of oxygen. Pathway B also occurs in the absence of oxygen and is known as alcoholic fermentation, as it produces ethanol. Therefore, the correct answer is that Pathway C occurs in the presence of oxygen.

Photosynthesis and cellular respiration are almost opposite processes because they have opposite effects on carbon dioxide levels in the atmosphere. During photosynthesis, plants take in carbon dioxide from the atmosphere and convert it into glucose, releasing oxygen as a byproduct. This process helps to reduce the amount of carbon dioxide in the atmosphere. On the other hand, during cellular respiration, organisms break down glucose and release carbon dioxide as a waste product, thereby putting it back into the atmosphere. Therefore, photosynthesis removes carbon dioxide from the atmosphere, while cellular respiration puts it back.

At the end of the electron transport chain, the electrons combine with oxygen and protons to form water. This is known as the final step of aerobic respiration, where oxygen acts as the final electron acceptor. The electrons are transferred from one molecule to another along the electron transport chain until they reach oxygen. The combination of electrons, oxygen, and protons produces water as a byproduct. This process is crucial for generating ATP, the energy currency of the cell, and is a fundamental step in cellular respiration.

In the absence of light, Chlorella cannot perform photosynthesis and therefore cannot take in carbon dioxide to produce glucose. However, cellular respiration still occurs in the dark, which requires the use of oxygen and produces carbon dioxide as a byproduct. This explains the negative uptake of carbon dioxide under dark conditions.

Fermentation and glycolysis are both anaerobic processes that occur in the cytoplasm of the cell. During fermentation, glucose is broken down into simpler molecules without the use of oxygen, producing a small amount of ATP. Glycolysis is the first step in cellular respiration, where glucose is converted into pyruvate, also without the use of oxygen, and a small amount of ATP is produced. Therefore, the correct answer is fermentation and glycolysis.

Lactic acid fermentation occurs in muscle cells. During intense exercise, when there is not enough oxygen available, muscle cells switch to anaerobic respiration to produce energy. This process involves the breakdown of glucose to lactic acid, which causes muscle fatigue and soreness. Therefore, lactic acid fermentation is a characteristic process that occurs in muscle cells during strenuous physical activity.

The electron transport chain (ETC) generates the most ATP during cellular respiration. This process occurs in the inner mitochondrial membrane and involves the transfer of electrons from electron carriers to generate a proton gradient. The protons then flow back through ATP synthase, driving the synthesis of ATP. The ETC is the final step in cellular respiration and produces the majority of the ATP molecules through oxidative phosphorylation. Glycolysis and the Krebs cycle also produce ATP, but they generate fewer molecules compared to the ETC. Fermentation does not produce ATP through oxidative phosphorylation and is therefore not the main source of ATP production.

During alcoholic fermentation, glucose is split into 3 pyruvic acid (pyruvate). This process generates 3 ATP molecules. However, since alcoholic fermentation occurs in the absence of oxygen, the electron carrier molecule NAD+ is regenerated to allow glycolysis to continue. NAD+ is necessary for the conversion of glucose to pyruvate in glycolysis, and without its regeneration, glycolysis would not be able to proceed, leading to a halt in energy production.

ATP molecules are formed during the process of aerobic cellular respiration. This process occurs in the mitochondria of the cell. Specifically, ATP molecules are formed in the mitochondrial matrix and the inner mitochondrial membrane. The mitochondrial matrix is the fluid-filled space inside the mitochondria, while the inner mitochondrial membrane is the membrane that surrounds the matrix. These locations provide the necessary enzymes and proteins for the production of ATP through the electron transport chain and oxidative phosphorylation. Therefore, the correct answer is "Mitochondrial matrix and inner mitochondrial membrane only."

The aerobic and anaerobic pathways of cellular respiration require pyruvic acid (pyruvate) and NADH. Pyruvic acid is the end product of glycolysis, which is the first step in both aerobic and anaerobic respiration. NADH is an important electron carrier that is produced during glycolysis and the Krebs cycle. These two molecules are necessary for the subsequent steps of cellular respiration, including the Krebs cycle and oxidative phosphorylation, where ATP is generated. ATP is not required for these pathways, but it is produced as a result of the energy released during cellular respiration.

During aerobic cellular respiration, a net gain of 2 ATP molecules is indeed produced during glycolysis. However, the Krebs cycle produces a total of 2 ATP molecules, not 4. The correct answer is that 4 ATP molecules are not produced during the Krebs cycle.

When yeast undergoes respiration, it produces carbon dioxide and ATP. Carbon dioxide is a byproduct of the breakdown of glucose during the process of cellular respiration. ATP is the energy molecule that is produced during cellular respiration and is used by cells for various metabolic processes. Therefore, the presence of ethanol in the yeast culture suggests that the yeast is undergoing fermentation, producing carbon dioxide and ATP as a result.