Basics Of Cellular Respiration

Cellular respiration is the process by which cells break down glucose to produce energy. It begins with glycolysis, which takes place in the cytoplasm and does not require oxygen. During glycolysis, glucose is converted into two molecules of pyruvate, releasing a small amount of ATP. This is the first step in cellular respiration and occurs in both aerobic and anaerobic conditions. Therefore, glycolysis is the correct answer.

The correct answer is the inner membranes of mitochondria. Electron transport chains are a series of protein complexes located in the inner membranes of mitochondria in eukaryotic cells. These chains play a crucial role in the process of oxidative phosphorylation, where electrons are transferred along the chain, resulting in the production of ATP. This process is a key step in cellular respiration, which is responsible for generating energy in eukaryotic cells.

The correct answer is NADH+FADH2/ 34 or 36 ATP. The electron transport chain is the final stage of cellular respiration, where NADH and FADH2 molecules generated from earlier steps donate their electrons to a series of protein complexes. As the electrons move through these complexes, energy is released and used to pump protons across the inner mitochondrial membrane. This creates an electrochemical gradient, which drives the synthesis of ATP through ATP synthase. The exact number of ATP molecules produced can vary, but on average, each NADH can generate about 3 ATP and each FADH2 can generate about 2 ATP. Therefore, the input/output of the electron transport chain is NADH+FADH2/ 34 or 36 ATP.

The correct answer is "Anaerobic pathways". Anaerobic pathways are pathways that can operate without the presence of oxygen. These pathways are used by organisms when there is a lack of oxygen available for energy production. During anaerobic respiration, glucose is broken down into smaller molecules to release energy without the use of oxygen. This process is less efficient than aerobic respiration, but it allows organisms to continue producing energy in oxygen-deprived environments.

In chemiosmosis, ATP is synthesized when electrons move from molecule to molecule in the electron transport chain (ETC). This process involves the transfer of electrons through a series of protein complexes, creating a proton gradient across the inner mitochondrial membrane. The movement of protons back across the membrane through ATP synthase drives the synthesis of ATP. Therefore, if electrons do not continue to move through the ETC, the proton gradient will not be maintained, and ATP synthesis through chemiosmosis will not occur. Hence, the statement is true.

Fermentation is a set of anaerobic pathways where pyruvic acid is converted into other organic molecules in the cytosol. This process occurs without the presence of oxygen. Therefore, the statement is true.

The actual number of ATP molecules generated can vary from cell to cell due to several factors. These factors include the efficiency of cellular respiration, the type of cell, the availability of oxygen and nutrients, and the metabolic activity of the cell. Additionally, different cells may have different energy demands and may produce ATP at different rates. Therefore, it is true that the actual number of ATP molecules generated can vary from cell to cell.

When one six-carbon molecule of glucose is oxidized, it is converted into pyruvic acid. This process is known as glycolysis, which occurs in the cytoplasm of cells. During glycolysis, glucose is broken down into two molecules of pyruvic acid, along with the production of a small amount of ATP. Pyruvic acid can then be further metabolized in the presence of oxygen to produce more ATP through the citric acid cycle and oxidative phosphorylation.

Ethyl alcohol is a product of alcoholic fermentation. Alcoholic fermentation is a metabolic process carried out by yeast in which glucose is converted into ethyl alcohol and carbon dioxide. Therefore, ethyl alcohol is the correct answer as it is the end product of this fermentation process.

The Kreb's Cycle, also known as the citric acid cycle, is the correct answer. It is the second stage of cellular respiration and occurs in the mitochondria. During this cycle, the remaining energy stored in glucose is extracted through a series of chemical reactions. It involves the oxidation of acetyl-CoA and produces ATP, NADH, FADH2, and carbon dioxide as byproducts. The Kreb's Cycle is an essential part of aerobic respiration and plays a crucial role in generating energy for the cell.

Glycolysis is the metabolic pathway that converts glucose into pyruvate. It is the first step in cellular respiration and occurs in the cytoplasm of cells. During glycolysis, one molecule of glucose is broken down into two molecules of pyruvate. Therefore, the correct answer is "Glucose/Pyruvate".

Pyruvic acid, a product of glycolysis, needs to enter the mitochondria to continue the process of cellular respiration. The mitochondrial membrane is responsible for regulating the movement of molecules in and out of the mitochondria. Therefore, pyruvic acid diffuses across the mitochondrial membrane to enter the mitochondrial matrix, where it undergoes further reactions in the Krebs cycle. The cristae are the inner folds of the mitochondrial membrane, and the shell is not a component of the mitochondria.

Aerobic respiration actually consists of three main stages: glycolysis, the citric acid cycle (Krebs cycle), and the electron transport chain. These stages occur in the presence of oxygen and are part of the metabolic process by which cells produce energy (in the form of adenosine triphosphate or ATP) from glucose and other organic molecules

When glycolysis occurs, the products can follow two pathways, depending on the presence or absence of oxygen. In the presence of oxygen, the products of glycolysis enter the aerobic respiration pathway, where they undergo further breakdown in the mitochondria. In the absence of oxygen, the products enter the anaerobic fermentation pathway, where they are converted into lactic acid or ethanol. Therefore, the statement that the products of glycolysis can follow three pathways is false.

When no more electrons enter the electron transport chain (ETC), ATP synthesis stops. This is because the ETC is responsible for generating a proton gradient, which is used to power the production of ATP. Without the flow of electrons in the ETC, the proton gradient cannot be maintained, and therefore ATP synthesis ceases.

When organic compounds are broken down and energy is released, several molecules are created. One of these molecules is ATP (adenosine triphosphate), which is the main energy currency of cells. ADP (adenosine diphosphate) is also formed, which can be converted back into ATP to store more energy. Additionally, phosphate molecules are released during this process. Therefore, all of the above options are correct as they represent the different molecules created when organic compounds are broken down and energy is released.