Chapter 7
Use the cellular respiration lab to help you answer the following questions. Which cellular respiration disruptors were given to Leif the action figure in the three images below
1. low oxygen, arsenic, diet pill 2.diet pill, arsenic, low oxygen
Compare and contrast lactic acid fermentation and ethanol fermentation (alcohol fermentation). Move each phrase to the appropriate category. If a phrase describes both types of fermentation, classify it as both
1. used by yeast cells,generates ethanol 2.anaerobic,generates nad 3.used by animal cells, produces lactic acid
Cellular respiration is carried out in the presence of oxygen (aerobic conditions) or the absence of oxygen (anaerobic conditions). Determine whether each of the following occur under aerobic conditions, anaerobic conditions, or both aerobic and anaerobic conditions
1.krebs cycle, electron transport chain 2.fermentation 3.glycolysis
The pyruvic acid from glycolysis can be converted to acetic acid, which can enter the citric acid cycle. Because this process is a cycle, the atoms entering the cycle must balance the atoms that leave. Consider carbon balance in the citric acid cycle. How many CO2 molecules leave the cycle for each acetic acid molecule that enters? For this question, assume that carbon only enters as acetic acid and exits as CO2. Note that acetic acid has two carbon atoms. You can determine the number of carbon atoms in carbon dioxide from its formula, CO2. Using the above answer, how many molecules of CO2 are directly generated by the citric acid cycle from 4 molecules of acetic acid? Again, in this question assume that carbon only enters as acetic acid and exits as CO2,
2co2, 8 co2
During glycolysis, glucose is broken down into two molecules of pyruvic acid. How many carbon atoms are in each pyruvic acid molecule?
3 carbon atoms
Pyruvate is a product of glycolysis and is subsequently converted to acetyl-CoA. Acetyl-CoA is a substrate for the citric acid cycle (CAC). Exactly how many molecules of glucose must be oxidized in glycolysis to provide the input for 8 turns of the CAC?
4
Which molecule is used as the primary source of chemical energy for tasks within a cell?
ATP
In general, what happens during an oxidation-reduction reaction between two molecules?
An atom in the oxidized molecule donates an electron as an atom in the reduced molecule attracts the electron.
Cytochromes are critical participants in the electron transport chains used in photosynthesis and cellular respiration. How do cytochromes donate and accept electrons?
Each cytochrome has an iron-containing heme group that accepts electrons and then donates the electrons to a more electronegative substance.
Adenosine triphosphate (ATP) is a molecule that provides energy for cellular functions. Label three major components of an ATP molecule.
three phosphate,ribose,adenine
When a person is sprinting, the person\'s muscle cells will begin using anaerobic respiration in addition to keeping the mitochondria respiring aerobically as much as the oxygen supply will allow. What benefits do muscle cells gain from anaerobic respiration in this situation?
For every glucose molecule that enters glycolysis, the cell generates, without oxygen, two ATP molecules that can keep the muscles moving. Adding electrons from NADH to pyruvate regenerates NAD , so that glycolysis can continue, and produces lactic acid, a waste product that can diffuse out of the cell
Anaerobic respiration allows a cell to break down carbohydrates in the absence of oxygen. Identify how NAD is used by animal cells during anaerobic respiration.
Glycolysis requires NAD produced from fermentation to produce ATP
Electron carrier molecules transfer electrons between metabolic pathways. Choose the electron carriers that transfer electrons from glycolysis to the electron transport chain and from the citric acid cycle to the electron transport chain. One of the molecules will be placed more than once, and one answer box will have two molecules.
Outside mito: Nadh, inside mito: nadh, fadh2
Cellular respiration consumes glucose during glycolysis. What product of glycolysis can be subsequently modified to enter the citric acid cycle under aerobic conditions
Pyruvate
Although the path of one glucose molecule through glycolysis generates a total of four ATP molecules, there is a net gain of only two ATP for each glucose molecule that enters the pathway. Why does the passage of one glucose molecule through glycolysis have a payoff of only two ATP molecules?
Two ATP molecules are used in the initial phase of glycolysis, reducing the net gain to two ATP.
Identify the oxidized substance, the reduced substance, the oxidizing agent, and the reducing agent in the following redox reaction:
Which substance gets oxidized? -Fe Which substance gets reduced? -Cu2 What is the oxidizing agent? -Cu2 What is the reducing agent? -Fe
Amino acids can be used as fuel during cellular respiration once the nitrogen-containing amine groups have been removed from them. When do amino acids that have had their amine groups removed enter the pathways of cellular respiration?
during glycolysis or during the Krebs cycle
The electron transport chain consists of protein complexes embedded in the inner mitochondrial membrane, where it generates a proton gradient by a series of oxidation-reduction, or redox, reactions. Although all the stages of cellular respiration (glycolysis, the citric acid cycle, and the electron transport chain) are necessary for life, the electron transport chain is sometimes called the most important stage. First complete the sentence, then answer the question below.
electrons It is potential energy that the cell uses to generate ATP
A proton gradient is formed in the mitochondria such that the concentration of protons (H ) is higher on one side of the inner mitochondrial membrane than on the other side. What is the purpose of this proton gradient
generates ATP in the electron transport chain
Glycolysis is a series of chemical reactions that convert glucose to pyruvic acid. Glycolysis also uses and generates chemical energy. Several compounds are necessary for glycolysis. These compounds are also components of other metabolic pathways in the cell. Match the compounds in the drop-down menus on the right with the descriptions on the left. You will not select all the compounds. You may select any compound more than once.
glucose, atp, pyruvic acid,nadh atp
Which of the following describes the effect of cyanide on cellular respiration?
inhibits the function of cytochrome c oxidase in the electron transport chain
Glycolysis is a step in the breakdown of glucose. Which of the following statements describe glycolysis?
it is common to aerobic and anaerobic respiration, it beaks down glucose to two pyruvate molecules.
The reaction pictured below is an oxidation-reduction reaction in the citric acid cycle in which the energy-carrier molecule, NADH, is generated. Identify which molecule in the reaction will be oxidized and which molecule will be reduced. Place a single answer choice in each box.
malate is oxidezed, nadh is reduced
Below are events that occur during cellular respiration. Identify where each of the events occur within a eukaryotic cell. Each cellular location may be used once, more than once, or not at all.
mitochondrial matrix, mitochondria membrane,cytosol, mitochondrial matrix
Identify compounds that are required for the electron transport chain and compounds that are produced by the electron transport chain. Not all the potential reactants or products are given. Place all the compounds
nadh,fadh2,o2,adp --->nad,fad,h20,atp
Carbon dioxide (CO2) is one of the products of the citric acid cycle, or Krebs cycle. Click on an arrow in the diagram below that coincides with a step at which CO2 is produced. Use the cellular respiration lab to help you answer the question.
right before succinate
Classify the following statements about the structure of an adenosine triphosphate (ATP) molecule as true or false. Reminder: Adenosine diphosphate is abbreviated ADP. Adenosine monophosphate is abbreviated AMP.
true, false,true,false,false,true
