Biology Chapter: Energy Metabolism

Organisms that obtain energy by consuming other organisms. They can be herbivores (eating plants) or carnivores (eating other animals).

Organic compounds broken down to extract energy. They are primarily carbohydrates but can include proteins, fats, and organic acids.

The process of releasing energy from food molecules through a series of controlled reactions within cells. It involves breaking down chemical bonds and capturing energy as ATP.

The main energy carrier in cells, formed during respiration. It provides energy for various cellular processes.

A series of chemical reactions controlled by enzymes, releasing energy from food molecules step by step.

The primary energy-producing organelle in eukaryotic cells, essential for cellular respiration.

Plants require oxygen for cellular respiration, just like animals, to break down food and generate energy.

The process by which green plants utilize sunlight to convert carbon dioxide and water into glucose (sugar) and oxygen.

The process of generating ATP directly from a substrate molecule, without the involvement of an electron transport chain. In the citric acid cycle, this occurs during the conversion of succinyl-CoA to succinic acid.

The first molecule in the citric acid cycle that reacts with Acetyl CoA to form Citric Acid.

A key enzyme in the citric acid cycle responsible for the conversion of α-ketoglutarate to succinyl-CoA. This step produces NADH and releases CO2.

A molecule crucial for energy production. It is regenerated from NADH during the electron transport chain and is required for the citric acid cycle to continue.

The process of removing electrons from a molecule, often accompanied by the removal of hydrogen ions (H+).

The process of adding electrons to a molecule, often accompanied by the addition of hydrogen ions (H+).

A crucial step in the citric acid cycle where a molecule of GTP is produced directly from a substrate, succinyl-CoA. This is an example of substrate-level phosphorylation.

A cycle that occurs in the mitochondria, where acetyl CoA is broken down into CO2, generating ATP, NADH, and FADH2. These products provide energy for the cell.

The summary equation for the Citric Acid Cycle (TCA cycle) shows the breakdown of pyruvate, generating CO2, NADH, FADH2, and ATP.

During the Citric Acid Cycle, glucose is broken down, releasing CO2 and producing eight molecules of NADH + H+, two molecules of FADH2, and just two molecules of ATP.

The electron transport system (ETS) is a series of protein complexes located in the inner mitochondrial membrane. It's responsible for using NADH + H+ and FADH2 to generate a proton gradient that ultimately fuels ATP synthesis.

In the ETS, electrons from NADH are oxidized by NADH dehydrogenase (complex I) and transferred to ubiquinone, a molecule embedded in the inner mitochondrial membrane.

Oxidative phosphorylation is the process of ATP synthesis coupled to the transfer of electrons through the Electron Transport System (ETS). It involves the use of a proton gradient generated by electron transport to drive ATP production.

Oxygen plays a crucial role in aerobic respiration by acting as the final electron acceptor in the electron transport system (ETS). This process leads to the formation of water and is essential for the ongoing production of ATP.

NADH + H+ and FADH2 are electron carriers produced during the Citric Acid Cycle (TCA cycle). They carry high-energy electrons that fuel the electron transport system (ETS), ultimately leading to ATP production.

The electron transport system (ETS) is located in the inner mitochondrial membrane. It consists of protein complexes that facilitate the transfer of electrons from NADH and FADH2 to oxygen, generating a proton gradient and driving ATP production.

The energy released during the electron transport chain is used by this enzyme complex to convert ADP and inorganic phosphate into ATP, the cell's energy currency.

A key component of ATP synthase, embedded in the inner mitochondrial membrane, forming a channel for protons to flow through.

A key component of ATP synthase located in the mitochondrial matrix, responsible for catalyzing the synthesis of ATP.

The difference in proton concentration between the intermembrane space and the mitochondrial matrix, creating a driving force for protons to move across the membrane through ATP synthase.

A series of reactions that break down glucose into pyruvate, generating a small amount of ATP and NADH, which are used in later stages of respiration. This process occurs in the cytoplasm of cells.

A cyclic series of reactions in the mitochondria, where pyruvate from glycolysis is further oxidized to produce CO2, ATP, NADH, and FADH2. These products provide essential energy carriers for the cell.

A process that occurs in the inner membrane of the mitochondria, where electrons from NADH and FADH2 are passed through a series of carrier molecules, releasing energy that is used to generate ATP. This process requires oxygen.

A type of respiration that occurs in the absence of oxygen. It results in the partial breakdown of glucose, producing a lower amount of ATP than aerobic respiration. Examples include fermentation in yeast and bacteria.

A process that releases energy from glucose in the presence of oxygen. It involves glycolysis, the Krebs cycle, and electron transport chain, resulting in a high yield of ATP.

The ratio of carbon dioxide produced to oxygen consumed during respiration. This value is influenced by the type of substrate being used. For example, fats have a lower RQ than carbohydrates.

The process of converting pyruvate from glycolysis into acetyl CoA, which then enters the Krebs cycle. This occurs within the mitochondria. This step releases carbon dioxide.