Chapter15

Question 1

Where is pyruvate transported ?

Answer 1

Across the outer and inner membrane of the mitochondria
2x pyruvate

Question 2

What happens before the citric acid cycle ?

Answer 2

Pyruvate converts into acetyl CoA and also produces one co2 and one NADH

Question 3

Prior to the cycle what does each molecule of glucose contain ?

Answer 3

4 NADH (2 from Glycolsis and 2 from doorway)
2CO2 ( both from the conversion of the 2 pyruvate)
2 ATP( glycolysis )
2 acetyl CoA

Question 4

What happens in the first step of the cycle ?

Answer 4

It’s the transfer of the acetyl group that enters the cycle
It (CoA) is transferred by the enzyme citrate synthase into citrate

Question 5

What happens in the second step?

Answer 5

The citrate with the help of the enzyme aconitase removes water and makes cis -aconitate
And then adds water again to make icocitrate

Question 6

What happens in the third step of the cycle ?

Answer 6

The enzyme isocitrate dehydrogenase oxidizes the isocictrate by NAD+ (INTO NADH + H+ AND CO2)
It forms alpha ketoglutarate

Question 7

What happens in the fourth step?

Answer 7

The alpha ketoglutrate looses a co2 and the co2 is oxidized by the NAD+ (co2 +NADH +H+) with the help of the enzyme ketoglutarate dehydrogenase
And acetylCoA also joins the molecule forming succinyl CoA

Question 8

What happens in the fifth step?

Answer 8

Succinyl CoA looses a phosphate group ( the loss of th phosphate makes 1 G3P and will make on ATP) and forms succinate by succinyl-CoA synthetase

Question 9

WHAT HAPPENS AT 6 STEP?

Answer 9

FAD will oxidize the succinate with the help of the enzyme succinate dehydrogenase and will make fumerate and FADH2

Question 10

What happens at the 7 stage ?

Answer 10

Fumerate will have the enzyme fumarase and will have an addition of water producing malate

Question 11

What happens in the final step?

Answer 11

In the final step malate is oxides by NAD+ into NADH and H+ by malate dehydrogenase and that enzyme will produce oxaloacetate

Question 12

How many times does the citric acid cycle go around for each glucose Mlcl?

Answer 12

2 times out
Produces 2 ATP
6NADH
2FADH2
4CO2

Question 13

WHAT ARE THE TWO IMPORTANT PRODUCTS

Answer 13

NADH AND FADH2

Question 14

After the citric acid cycle how many NADH have been made and how many FADH2

Answer 14

6 NADH2
2 FADH2

Question 15

What do FADH2 and NADH have ?

Answer 15

They carry high energy electrons with potential energy
This stores energy is used to start atp synthesis in the process of oxidative phosphorylation

Question 16

What happens after NADH and FADH2 have the electrons ?

Answer 16

The electrons are transferred from one electron to another carrier to another in a stepwise fashion
Until the electrons combine O2 with H+
To form H2O

Question 17

What is the electron transfer chain ?

Answer 17

The series of transfers of electrons to electron carriers

Question 18

What are the electron carrier?

Answer 18

multiprotein complexes that have prosthetic groups(no protein components) that are found int he inner membrane of the mitochondrian

Question 19

What happens when electrons are transferred from one carrier to another?

Answer 19

One becomes oxidized and the Carrier that accepts the electrons becomes reduced
The reduced carrier than donates the electrons to the next chain where it will be oxidized

Question 20

What is oxidatative phosphorylation ?

Answer 20

The process by which atp is made from energy released by the electron transport chain

Question 21

What does OP use?

Answer 21

Redox Rxns in an electron transport chain to produce the energy needed to attach Pi it ADP to make ATP

Question 22

What is the enzyme that makes ADP into ATP?

Answer 22

ATP synthase

Question 23

What is the reaction that makes atp from ADP ?

Answer 23

The reaction is endergonic and the ion gradient of H + that exists across the inner mitochondrial membrane gives the cell the energy

Question 24

How is the H+ gradient generated ?

Answer 24

By the ETC
When electrons are transferred from one carrier to the next a small amount of energy is released

It is the energy that is used to pump the H+ across the membrane from the matrix to the inter membrane space by ec

Question 25

What do the electrons pick up and release when they pick up electrons

Answer 25

Release protons

Question 26

What is the proton motive force ?

Answer 26

The H+ gradient that exists
After movement into the intermembrane space there is now an electrochemical difference across the inner membrane

Question 27

How does H+ diffuse across the membrane ?

Answer 27

Can’t diffuse on its own because its an ion
Passes through the channels made by atp synthase
The atp synthase utilizes the PMF to phosphorylate ADP to make ATP

Question 28

How is the energy derived from the redox reactions of cellular respiration used?

Answer 28

To attach Pi to ADP to make ATP

Question 29

What is an example for chemical work

Answer 29

Making atp with the energy source of the proton gradient made by the electron transport chain

Question 30

What is chemiosomosis

Answer 30

An energy coupling mechanism that makes use for a proton gradient to drive cellular work

Question 31

What is An example of chemiosomosis

Answer 31

Mitochondria make use of chemiosomosis to do chemical work (make atp)
Plants make use of chemiosomosis to transfer molecules (proton pump)
Bacteria = makes use of the chemiosomosis I it rotate flagell

Question 32

What is the maximum yield of ATP obtained in cellular respiration per glucose mlcl?

Answer 32

30-32 molecules atp

Question 33

For each NADH molecule that passes electrons to the ETC_____ Aare pumped out

Answer 33

10 H+ are pumped out

Question 34

How is the total production of ATP 30-32?

Answer 34

Basically every 4H+ make 1 atp so you divide 10 (NADH) by 4( # of H+) making it 2.5 atp per one NADH
And for 1 FADH2 molecule you would divide 6( fadh2) by 4 making 1.5 atp per one FADH2
Multiple the numbers with the total numbers of fadh2 and NADH for maximum yeild including the 4 from glycolysis and cac

Question 35

Why is there a range for ATP produced per mlcl of glucose ?

Answer 35

It depends on the type of cell
Heart and li liver cells electron shadow system passes the electron to NAD plus
In the brain and muscle, the shadow system passes the electrons to FAD
If FAD the cell will make less ATP from the FDH2 (30-32)

Question 36

What intermediate of glycolysis and the citric acid cycle be

Answer 36

They can be diverted into anabolic pathways in which the cell makes the molecules that it needs
Intermediate,
the citric acid cycle can be used to make amino acids
Fatty acids can be made from acetyl CoA

Question 37

Catabolic pathways?

Answer 37

If the cell. Is working hard and the amount of atp drops cellular respiration increases
If there is plenty of ATP the cellular respiration decreases