Cellular respiration
Terms : Hide Images
| 507302846 | fermentation | partial degradation of sugars that occurs without oxygen | |
| 507302847 | What happens during cellular respiration? | The oxidation of glucose transfers electrons to a lower energy state, liberating energy available for ATP synthesis | |
| 507302848 | aerobic respiration | oxygen is consumed as a reactant along with the organic fuel. | |
| 507302849 | formula for cellular respiration | C6H12+6O2-> 6 CO2+6 H2O+ Energy (Heat+ATP) | |
| 507302850 | The cell must regenerate ATP from____ | ADP and P (phosphate group) | |
| 507302851 | redox reactions | Reactions during which an electron transfer takes place (oxidation or reduction) | |
| 507302852 | Why does adding electrons result in a reduction? | Adding negatively charged electrons reduce the amount of positive charge of that ion | |
| 507302853 | the electron donor is called the _______ and the electron receiver is called the ________ | reducing agent, oxidizing agent | |
| 507302854 | Why are organic molecules with an abundance of hydrogen excellent fuels? | Their bonds are a source of "hilltop" electrons whose energy may be released as these electrons "fall" down an energy gradient when they are transferred to oxygen. | |
| 507302855 | Why is it important to have a barrier of activation? | Without the barrier, glucose would combine almost instantaneously with O2 | |
| 507302856 | What does enzymes allow your body to do? | Enzymes win your cells will lower the barrier of activation energy, allowing sugar (glucose) to be oxidized in a series of steps | |
| 507302857 | How does cellular respiration oxidize glucose? | Glucose and other organic fuels are broken down in a series of steps. At key steps, electrons are stripped from glucose. | |
| 507302858 | Explain what happens when electrons are stripped from glucose. | Electrons are stripped from glucose at key steps. Each electron travels with a proton, thus as a hydrogen atom. | |
| 507302859 | How are hydrogen atoms transferred directly to oxygen? | Through an electron carrier, a coenzyme called NAD+ | |
| 507302860 | What does NAD+ function as during cellular respiration? | an electron acceptor/ an oxidizing agent in cellular respiration | |
| 507302861 | How does NAD+ trap electrons from glucose and other organic molecules? | enzymes called dehydrogenases remove a pair of hydrogen atoms (2 electrons and 2 protons) from the substrate (glucose). The enzyme delivers the 2 electrons along with one proton to its coenzyme, NAD+, and the other proton is released as a hydrogen ion into the surrounding solution | |
| 507302862 | How and why is NAD+ transformed into NADH? | By receiving 2 negatively charged electrons but only one positively charged proton, NAD+ is reduced to NADH, and its charge is neutralized. | |
| 507302863 | describe the concept of the electron transport chain | electrons cascade down a chain from one carrier molecule to the next in a series of redox reactions, losing a small amount of energy with each step until they finally reach oxygen, the terminal oxygen acceptor, which has a great affinity for electrons. | |
| 507302864 | Electrons increase in ________ as they move down the ETC | electronegativity | |
| 507302865 | What happens to electrons removed by NAD+? | They fall down an energy gradient in the electron transport chain to a far more stable location in the electronegative oxygen atom. | |
| 507302866 | What is the downhill route of electrons? | glucose->NADH->electron transport chain->oxygen | |
| 507302867 | three metabolic stages of cellular respiration | glycolysis, the citric acid cycle, and oxidative phosphorylation (ETC and chemiosmosis) | |
| 507388945 | Glycolysis (location and basic function) | begins in the cytosol and begins the degradation process of breaking down glucose into two molecules called pyruvate | |
| 507388946 | Citric acid cycle (location and basic function) | takes place in the mitochondrial matrix or cytosol of prokaryotes, completes the breakdown of glucose by oxidizing the derivative of pyruvate to carbon dioxide | |
| 507388947 | What happens during the third stage of respiration? | the electron transport chain accepts electrons from the breakdown of the first two stages (via NADH) and passes these electrons from one molecule to another. At the end of the chain, electrons are combined with molecular oxygen and hydrogen atoms, forming water. | |
| 507388948 | What is the mode of ATP synthesis called that is powered by redox reactions of the electron transport chain? | oxidative phosphorylation | |
| 507388949 | substrate-level phosphorylation | A small amount of ATP is formed directly in a few reactions of glycolysis and the citric acid cycle. (In other words, some ATP is made by direct transfer of a phosphate group from an organic substrate to ADP by an enzyme) | |
| 507388950 | when does ATP synthesis occur? | when an enzyme transfers a phosphate group from a substrate molecule to ADP, rather than adding an inorganic phosphate to ADP as in oxidative phosphorylation | |
| 507388951 | substrate molecule | an organic molecule generated as an intermediate during the catabolism of glucose | |
| 507388952 | For each molecule of glucose degraded to carbon dioxide and water by respiration, the cell makes about _________ molecules of ATP | 36-38 | |
| 507388953 | What two phases can glycolysis be split into? | energy investment and energy payment phase | |
| 507388954 | What occurs during the energy investment phase of glycolysis? | the cell uses 2 ATP | |
| 507388955 | What happens during the energy payoff phase? | 4 ATP are formed, 2 NADH + 2 H+ and 2 pyruvate molecules plus 2 H2O | |
| 507388956 | What are the net products of glycolysis? | glucose-> 2 pyruvate+2H2O 4 ATP formed-2ATP used->2 ATP 2 NAD+ + 4e +4H-> 2 NADH+2H+ | |
| 507388957 | What happens if oxygen is not present during glycolysis? | fermentation | |
| 507388958 | Two types of fermentation | lactic acid and alcoholic | |
| 507388959 | lactic fermentation | creates lactic acid for the muscle cells pyruvic acid + NADH-> lactic acid | |
| 507388960 | alcoholic fermentation | yeast cells create alcohol pyruvic acid +NADH-> alcohol+CO2+NAD | |
| 507388961 | What is the starting molecule of the krebs cycle? | acetyl CoA (converted from pyruvic acid) | |
| 507388962 | Describe the conversion of pyruvate to acetyl CoA | Pyruvate's carboxyl group, which is already fully oxidized, is removed and given off as CO2. The remaining two-carbon fragment is oxidized, forming a compound named acetate. An enzyme transfers the extracted electrons to NAD+, storing energy in the form of NADH. Finally, conenzyme A is attached to the acetate by an unstable bond, making the molecule highly reactive. | |
| 507475890 | What happens during the citric acid cycle? | pyruvate is broken down into three CO2 molecules. The cycle generates 1 ATP per turn by substrate-level phosphorylation, and most of the energy is transferred to NAD+ and coenzyme FAD. The first intermediate, citrate, is converted to its isomer be the removal of one water molecule and the addition of another. The last intermediate, oxaloacetate, oxidizes the substrate, reducing NAD+ to NADH and regenerating oxaloacetate. | |
| 507475891 | what are the net products of the citric acid cycle? | 2 ATP + 6NADH and 2FADH2 | |
| 507475892 | What is the electron transport chain | collection of molecules embedded in the inner membrane of the mitochondrion | |
| 507475893 | What are most components of the ETC made of? | protein | |
| 507475894 | What happens along the ETC? | electron carriers alternate between reduced and oxidized states as they accept and donate electrons. | |
| 507475895 | What is the passage of electrons accompanied by? | Formation of a proton gradient across the inner mitochondrial membrane, separating a region of high proton concentration from a region of low proton concentration | |
| 507475896 | In the krebs cycle_______ is released from organic intermediates and ATP is synthesized from ________ and inorganic phosphate via ______ phosphorylation and electrons are captured by conenzymes. | CO2, ADP, Substrate-level | |
| 507475897 | What does the ETC do? | It eases the fall of electrons from food to oxygen, breaking a large free-energy drop into a series of smaller steps. | |
| 507475898 | ATP synthase (location and function) | the enzyme that makes ATP from ADP and inorganic phosphate, inner membrane | |
| 507475899 | how does ATP synthase power ATP synthesis? | Uses the energy of an existing ion gradient. The power source is a difference in the concentration of H+ on opposite sides of the inner mitochondrial membrane | |
| 507475900 | Chemiosmosis | process in which energy stored in the form of a hydrogen ion gradient across a membrane is used to drive cellular work such as the synthesis of ATP | |
| 507475901 | ATP synthase | protein complex that functions as a mill, powered by the flow of hydrogen ions. (This produces ATP from ADP+P) | |
| 507475902 | The ETC is an energy converter that uses the flow of electrons from ______and _________ to pump H+ across the membrane. | NADH and FADH2 | |
| 507475903 | ATP synthase are the only sites that provide _______ | a route for H+ through the membrane | |
| 507475904 | Function of ATP synthase | use the exergonic flow of H+ to drive the phosphorylation of ADP. The energy stored in an H+ gradient across the membrane couples the redox reactions of the electron transport chain to ATP synthesis | |
| 507475905 | oxidative phosphorylation | ADP plus a phosphate group creates ATP | |
| 507475906 | cellular respiration and fermentation use ________ available from sugars and from interconnected pathways (__________), to phosphorylate ADP, creating what? | free energy, glycolysis and the krebs cycle, ATP | |
| 507475907 | what is entropy? | disorder of a system | |
| 507475908 | What is free energy? | energy available |
