Test Four: Lecture #3

Question 1

After NADH is produced from the process of glycolysis, which statement does not describe how can it be used within the cell?

Answer 1

Aerobic Respiration: NADH is used at the end of the process in the ETC. Specifically the H is removed and used to make ATP.

Question 2

Once glycolysis is complete, the first step within the first process of aerobic respiration is the oxidation of pyruvate. Where in the mitochondria does this process take place?

Answer 2

It takes place in the intermembrane space

Question 3

Once glycolysis is complete, the first step within the first process of aerobic respiration is the oxidation of pyruvate. What is the equation of this process? (i.e. know the reactants and products we discussed and the equation which was on the board)

Answer 3

Pyruvate + NAD+ +CoA → Acetyl - CoA + NADH

Question 4

After pyruvate oxidation is complete, acetyl Co-A is produced. Which statement describes a way acetyl-CoA can be used within your body? (we discussed two main ways)

Answer 4

Energy Storage: The body will store as much energy as it needs and can expend anything else consumed becomes extra. The extra is useless and is eventually converted into fat. This is how weight gain occurs.
Krebs Cycle: If energy levels are low then ATP will be produced. This happens because Acetyl-CoA goes through a process called the krebs cycle.

Question 5

After pyruvate oxidation is complete, acetyl Co-A is produced. Acetyl Co-A can then be used within your cells in two main ways. __________ takes place if the ATP level is high within the cell and ____________ takes place if the ATP level is low within your cell. Fill in the blanks.

Answer 5

Energy Storage; Krebs Cycle

Question 6

Where within the mitochondria does the Krebs cycle (the citric acid cycle) take place?

Answer 6

In the mitochondrial matrix (basically in the center)

Question 7

Which statement describes any steps, reactants, or products of segment A of the Krebs cycle?

Answer 7

Acetyl CoA is attached to 4 carbon molecules called oxaloacetate. CoA kickstarts the program. Once the molecules are together in the Matrix, CoA will detach and go back to pyruvate oxidation to be reloaded. You’re then left with a 6 carbon molecule, called citrate.

Question 8

Which statement describes any steps, reactants, or products of segment B of the Krebs cycle?

Answer 8

Step 1: one of the carbons will be removed and attached to oxygen and you’ll be left with carbon dioxide. When you remove stuff (oxidize) Hydrogen is released so it bonds with NAD+ and forms NADH (goes to ETC). Last thing left is a 5 carbon molecule because 1 was broken off.
Step 2: Another carbon is broken off, what was once citrate, then carbon dioxide gets created. Then again NADH gets created. And because you removed another carbon you’re left with a 4 carbon molecule.
Step 3: You are creating a tiny bit of ATP, because you take the 4 carbon molecules, which at one point had phosphates, and you’re removing those phosphates to create very little ATP.

Question 9

Which statement describes any steps, reactants, or products of segment C of the Krebs cycle?

Answer 9

You have a 4 carbon molecule. It’ll be oxidized and stays 4 carbons the entire time, but you are taking hydrogens off and creating some double bonds instead. FADH2 is created alongside NADH, because the hydrogens are removed NAD and FAD are reduced. Will end with 4 carbon molecules, no decarboxylation. To create energy FADH and NADH are sent to ETC.

Question 10

Where within the mitochondria does the ETC (electron transport chain) take place?

Answer 10

In the inner mitochondrial membrane

Question 11

What is the proper order of the enzymes and carriers used within the electron transport chain?

Answer 11

NADH Dehydrogenase, Ubiquinone (Q), Intermediate Step, BC1 Complex, Cytochrome C, and Cytochrome Oxidase

Question 12

What is the function of NADH dehydrogenase within the ETC?

Answer 12

NADH is put in an enzyme, removes its hydrogen and becomes NAD+. And the Hydrogen will go to an area where it’ll drive a gradient that eventually powers the pump; energy is simultaneously being released

Question 13

What is the function of Ubiquinone (Q) within the ETC?

Answer 13

carrier that passes the electrons along the electron chain

Question 14

What is the function of the BC1 complex within the ETC?

Answer 14

Operates as a proton pump driving protons across the membrane

Question 15

What is the function of Cytochrome c within the ETC?

Answer 15

Another carrier that moves electrons along the chain

Question 16

What is the function of Cytochrome oxidase within the ETC?

Answer 16

It takes the unwanted hydrogens from the matrix and creating water

Question 17

Which statement accurately describes how the ATP is produced at the end of the ETC (know ALL information we discussed about the proton gradient and how it works)?

Answer 17

The hydrogen comes in through the pump, being turned like a turbine, to create ATP, driven also by a proton gradient.

Question 18

What occurs during the process of chemiosmosis?

Answer 18

Just means you are producing ATP. Chemical formation of ATP driven by a diffusion force.

Question 19

The electron transport chain is an area the accepts the electrons transferred within the mitochondria that consist of a series of membrane-associated proteins. What is the function of ATP synthase within the ETC?

Answer 19

Enzyme used to create ATP; Means you are synthesizing ATP.

Question 20

Which statement does not describe a step of the electrons transport chain (ETC)?

Answer 20

Electrons are harvested and carried to the transport system, electrons provide energy to pump protons across the membrane, oxygen joins with protons to form water, protons diffuse back down their concentration gradient, driving the synthesis of ATP.

Question 21

What is the theoretical and actual yield of ATP produced by aerobic respiration in eukaryotes?

Answer 21

Theoretical Yield: The amount of ATP produced in a perfect situation
Actual Yield: Actual amount of ATP produced in a mammals body relative to the setbacks due to entropy

Question 22

Why is the actual yield of ATP produced during aerobic respiration less than the theoretical yield which should occur? (know the two reasons we discussed in class)

Answer 22

Because of a leaky membrane and the proton gradient.

Question 22

Due to varying reasonings discussed in class, aerobic respiration only uses _______ (percent) of energy within one original glucose molecule. Fill in the blank.

Answer 22

32%

Question 23

Aerobic respiration has different control points along its enzymatic pathway to not allow it to continue unless needed. One of the first control points occurs during glycolysis using the enzyme called phosphofructokinase. What things occurring in your cell can turn this enzymes on and off? (know all the conditions we discussed in class)

Answer 23

High levels of ADP → process turns on
High ATP present → this will stay off

Question 24

The second control point occurs right before the Krebs cycle begins using the enzyme called pyruvate dehydrogenase. What things occurring in your cell can turn this enzymes on and off? (know all the conditions we discussed in class)

Answer 24

Low levels of citrate → this will turn on and allow process to happen
High levels of Citrate → cycle won’t begin (because you don’t need it)
High NADH → turn off (no reason to produce anymore)
Low levels of NADH → turns on (you probably need the energy)

Question 25

The third control point occurs at the beginning of the the Krebs cycle using the enzyme called citrate synthase. What things occurring in your cell can turn this enzymes on and off? (know all the conditions we discussed in class)

Answer 25

High levels of ATP → turn off (not need to create process)
Low levels of ATP → turn on to create ATP