Questions
At the end of the electron transport chain the electrons are taken up by oxygen to generate

At the end of the electron transport chain the electrons are taken up by oxygen to generate 

  • ATP
  • heat
  • glucose
  • water

In: Biology

What process occurs in box a?

What process occurs in Box A?

In: Biology

Watch this video and then use the figure below to answer the question

Watch this video and then use the figure below to answer the questions.

Part A

Match each component of the electron transport chain with its description.

Drag the terms on the left to the appropriate blanks on the right to complete the sentences.

 

In: Biology

When the protein gramicidin is integrated into a membrane, an H+ channel forms and the membrane becomes very permeable to protons (H+ ions).

When the protein gramicidin is integrated into a membrane, an H+ channel forms and the membrane becomes very permeable to protons (H+ ions). If gramicidin is added to an actively respiring muscle cell, how would it affect the rates of electron transport, proton pumping, and ATP synthesis in oxidative phosphorylation? (Assume that gramicidin does not affect the production of NADH and FADH2 during the early stages of cellular respiration.)

Sort the labels into the correct bin according to the effect that gramicidin would have on each process.

[The following are some hints to help you approach the problem.]

You know that membranes treated with gramicidin become very leaky to protons. Consider these four questions (in this order) to help you evaluate how gramicidin alters oxidative phosphorylation

1. Is a proton gradient across the inner mitochondrial membrane required for ATP synthesis during oxidative phosphorylation?

2. What effect does a membrane that is very leaky to protons have on the ability of the mitochondrion to maintain a proton gradient across that membrane?

3. What effect does the ability of the mitochondrion to maintain a proton gradient have on the rate of proton pumping?

4. How is the rate of electron transport related to the rate of proton pumping, and are these rates affected by the membrane being leaky to protons? 

In: Chemistry

The four stages of cellular respiration do not function independently Instead

The four stages of cellular respiration do not function independently Instead, they are coupled together because one or more outputs from one stage functions as an input to another stage The coupling works in both directions, as indicated by the arrows m the diagram below. In this activity, you will identify the compounds that coupe the stages of cellular respiration.

Drag the labels on the left onto the diagram to Identify the compounds that couple each stage Labels may be used once, more than once, or not at all

In: Biology

During acetyl CoA formation and the citric acid cycle, all of the carbon atoms that enter cellular respiration in the glucose molecule are released in the form of CO2.

Part A - Carbon atoms in acetyl CoA formation and the citric acid cycle

During acetyl CoA formation and the citric acid cycle, all of the carbon atoms that enter cellular respiration in the glucose molecule are released in the form of CO2. Use this diagram to track the carbon-containing compounds that play a role in these two stages.

Drag the labels from the left (which represent numbers of carbon atoms) onto the diagram to identify the number of carbon atoms in each intermediate in acetyl CoA formation and the citric acid cycle. Labels may be used more than once.

Part B - Net redox reaction in acetyl CoA formation and the citric acid cycle

In the sequential reactions of acetyl CoA formation and the citric acid cycle, pyruvate (the output from glycolysis) is completely oxidized, and the electrons produced from this oxidation are passed on to two types of electron acceptors.

Drag the labels on the left to show the net redox reaction in acetyl CoA formation and the citric acid cycle. Note that two types of electron carriers are involved.

Part C - Why is the citric acid cycle a cyclic pathway rather than a linear pathway?

In the oxidation of pyruvate to acetyl CoA, one carbon atom is released as \(\mathrm{CO}_{2}\). However, the oxidation of the remaining two carbon atoms-in acetate- -to \(\mathrm{CO}_{2}\), requires a complex, eight-step pathway-the citric acid cycle. Consider four possible explanations for why the last two carbons in acetate are converted to \(\mathrm{CO}_{2}\) in a complex cyclic pathway rather than through a simple, linear reaction.

  • Use your knowledge of the first three stages of cellular respiration to determine which explanation is correct.
  • More ATP is produced per \(\mathrm{CO}_{2}\), released in cyclic processes than in linear processes.
  • It is easier to remove electrons and produce \(\mathrm{CO}_{2}\) from compounds with three or more carbon atoms than from a two-carbon compound such as acetyl CoA.
  • Redox reactions that simultaneously produce \(\mathrm{CO}_{2}\) and NADH occur only in cyclic processes.
  • Cyclic processes, such as the citric acid cycle, require a different mechanism of ATP synthesis than linear processes, such as glycolysis.

In: Biology

The ATP that is generated in glycolysis is produced by substrate-level phosphorylation

ATP synthesis in glycolysis substrate-level phosphorylation

The ATP that is generated in glycolysis is produced by substrate-level phosphorylation, a very different mechanism than the one used to produce ATP during oxidative phosphorylation. Phosphorylation reactions involve the addition of a phosphate group to another molecule.

Sort the statements into the appropriate bin depending on whether or not they correctly describe some aspect of substrate-level phosphorylation in glycolysis.

In: Chemistry

Among the products of glycolysis, which compounds contain energy that can be used by other biological reactions?

Among the products of glycolysis, which compounds contain energy that can be used by other biological reactions?

  • a) ATP only
  • b) pyruvate, ATP, and NADH
  • c) CO2 only
  • d) O2 only
  • e) pyruvate and ATP only
  • f)  NADH only
  • g) ATP and NADH only

In: Biology

In glycolysis, as in all the stages of cellular respiration, the transfer of electrons from electron donors to electron acceptors plays a critical role in the overall conversion of the energy in foods to energy in ATP.

Part A - Redox (oxidation-reduction) reactions in glycolysis

In glycolysis, as in all the stages of cellular respiration, the transfer of electrons from electron donors to electron acceptors plays a critical role in the overall conversion of the energy in foods to energy in ATP. These reactions involving electron transfers are known as oxidation-reduction, or redox, reactions.

Drag the words on the left to the appropriate blanks on the right to complete the sentences.

  • 1. When a compound donates (loses) electrons, that compound becomes . Such a compound is often referred to as an electron donor.
  • 2. When a compound accepts (gains) electrons, that compound becomes ___________ . Such a compound is often referred to as an electron acceptor.
  • 3. In glycolysis, the carbon-containing compound that functions as the electron donor is
  • 4. Once the electron donor in glycolysis gives up its electrons, it is oxidized to a compound called
  • 5. ____________ is the compound that functions as the electron acceptor in glycolysis.
  • 6. The reduced form of the electron acceptor in glycolysis is.