Lecture 3: 12/05/22

Question 1

After NADH is produced from the process of glycolysis, which statement describes how can it be used within the cell?

Answer 1

Aerobic Respiration, Fermentation → Acetaldehyde, Lactic Acid & Ethanol

Question 2

Where in the mitochondria does pyruvate oxidation take place?

Answer 2

done in the intermembrane space

Question 3

What is the equation of pyruvate oxidation?

Answer 3

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

Question 4

What ways can acetyl-CoA can be used within your body?

Answer 4

energy storage and 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.

Answer 5

Energy/Fat Storage, Krebs Cycle

Question 6

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

Answer 6

mitochondrial matrix

Question 7

What are the steps, reactants and products of segment A of the Krebs cycle

Answer 7

acetyl CoA (coenzyme and two carbons, created during pyruvate oxidation) attached to 4 carbon molecules called oxaloacetate (left over from previous cycle since krebs are continuous). 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

What are the steps, reactants and products of segment B of the Krebs cycle

Answer 8

only time in the Krebs Cycle that ATP is being produced

Question 9

What are the steps, reactants and products of segment C of the Krebs cycle

Answer 9

Acetyl - CoA → 2CO2 + 2ATP + 3NADH +FADH2 +Acetyl CoA

Question 10

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

Answer 10

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) → BC1 Complex → Cytochrome c → Cytochrome Oxidase

Question 12

What is the function of NADH dehydrogenase within the ETC?

Answer 12

first enzyme used. 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. When you do this because it’s being broken, energy is simultaneously being released, which allows you to go to the next step

Question 13

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

Answer 13

carrier that passes the electrons along the electron chain. The electron will power the chain and make it function. The name is derived from this because you are transferring electrons as they’re simultaneously being created from broken bonds.

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. The pump is powered by the electrons that are continuously removed, when NADH and FADH2 are being oxidized (basically gaining energy from that process). Only job is to drive them across the membrane to have a high concentration, because you are trying to build that high concentration gradient.

Question 15

What is the function of Cytochrome c within the ETC?

Answer 15

Another carrier that moves electrons along the chain. The same thing as Ubiquinone, just know the order of each step.

Question 16

What is the function of Cytochrome oxidase within the ETC?

Answer 16

Hydrogen and Oxygen combine to form water. Oxygen is the final electron acceptor, so it’ll take any leftover hydrogens you have to form water. Don’t want a high amount of oxygen in the mitochondrial matrix, you want them in a high amount in the intermembrane space, so basically taking unwanted hydrogens from the matrix and cratingwater. This allows you to have a high concentration gradient in the intermembrane space.

Question 17

What describes how the ATP is produced at the end of the ETC?

Answer 17

a. when the concentration gradient of protons in the intermembrane space is too high they go to an area of low concentration in the matrix and it’ll power this process
b. ATP Synthase: Enzyme used to create ATP. Powered by the concentration gradient.

Question 18

What occurs during the process of chemiosmosis?

Answer 18

producing ATP

Question 19

What is the function of ATP synthase within the ETC?

Answer 19

Enzyme used to create ATP. Powered by the concentration gradient.

Question 20

Electron Transport Chain (ETC)

Answer 20

look at diagram

Question 21

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

Answer 21

36 and 30

Question 22

Why is the actual yield of ATP produced during aerobic respiration less than the theoretical yield which should occur?

Answer 22

There is leaking in the inner mitochondrial matrix and it allow all the hydrogens to travel through the synthase. Because some just enter the matrix naturally, they want to go from high to low concentration (proton gradient)

Question 23

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

Answer 23

32%

Question 24

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?

Answer 24

High levels of ADP → process turns on (eans you want to create ATP)
High ATP present → this will stay off (can only hold so much)

Question 25

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?

Answer 25

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 26

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?

Answer 26

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