aerobic cellular respiration

Question 1

cellular respiration definition

Answer 1

process by which cells create useable energy in the form of ATP from a series of biochemical reactions involving the breakdown of glucose

Question 2

what are the 2 pathways by which cellular respiration occurs?

Answer 2

aerobic cellular respiration and anaerobic fermentation

Question 3

what is the difference between these 2 pathways?

Answer 3

the absence of oxygen

Question 4

stage 1 of aerobic cellular respiration?

Answer 4

glycolysis

Question 5

where does glycolysis occur?

Answer 5

cytosol of the cell

Question 6

inputs for glycolysis?

Answer 6

1 glucose
2 ADP + 2PI
2NAD+ + 2H+

Question 7

outputs for glycolysis?

Answer 7

2 pyruvate
2 ATP
2 NADH

Question 8

what happens when glucose is broken down into pyruvate? what does the product of that break down aid in?

Answer 8

energy is released that can be harnessed by the cell. this energy powers the reactions of 2ADP + PI into 2ATP, which is now free to power cellular reactions.

Question 9

What does the breakdown of 2NAD+ + 2H+ into 2NADH allow for?

Answer 9

the breakdown of 2NAD+ + 2H+ into 2NADH allows for electrons and protons to be transported to the mitochondria, but they are modified and broken down in the krebs cycle first.

Question 10

what exactly happens to the 2NAD+ + 2H+ into 2NADH

Answer 10

the 2NAD+ + 2H+ reduces into 2NADH so that it can accept those protons and electrons

Question 11

what happens to the pyruvate and NADH that is produced in glycolysis?

Answer 11

it goes on to make even more ATP in krebs cycle and electron transport chain.

Question 12

where does the krebs cycle occur?

Answer 12

mitochondrial matrix

Question 13

what is the link reaction?

Answer 13

link reaction links glycolysis and krebs cycle, whereby pyruvate is transported the the matrix of the mitochondria and forms acetyl coa. also produces nadh for later use at the electron transport chain and one wasteful co2.

Question 14

inputs for krebs cycle?

Answer 14

2-acetyl coa
2ADP + PI,
6NAD+ + 6H+
2 FAD + 4H+

Question 15

outputs for krebs cycle?

Answer 15

4 CO2
2 ATP
6 NADH
2 FADH2

Question 16

what happens when acetyl coa in the krebs cycle breaks down?

Answer 16

high energy electrons are released. these electrons are loaded on to NAD+ and FAD molecules to generate NADH and FADH2

Question 17

how many pyruvates produce one wasteful CO2 product?

Answer 17

2 pyruvates

Question 18

what is the krebs cycle?

Answer 18

The second stage of aerobic cellular respiration is the Krebs cycle. It occurs in the matrix of mitochondria and it produces four CO2, two FADH2, six NADH, and two ATP for every two pyruvate molecules created via glycolysis.

Question 19

in what form does the krebs cycle produce a small amount of energy in?

Answer 19

2atp (one per acetyl coa molecule)

Question 20

how many molecules of co2 are produced for every original glucose molecule?

Answer 20

6co2 molecules are produced for every original glucose molecule.

Question 21

why does the krebs cycle occur twice

Answer 21

because each glucose molecule is broken down into 2 pyruvates, and each pyruvate breaks down into 1 acetyl coa molecule, meaning 2 acetyl coa are produced for each pyruvate.

Question 22

what is stage 3 of aerobic cellular respiration?

Answer 22

the electron transport chain

Question 23

location of the electron transport chain?

Answer 23

cristae of mitochondria

Question 24

what happens during the electron transport chain?

Answer 24

energy from electrons unloaded by NADH and FADH2 generates a proton gradient that drives significant ATP production by ATP synthase.

Question 25

what happens to the loaded coenzymes nadh and fadh2 in electron transport chain?

Answer 25

they are converted back into NAD+ and FAD+, which are then recylced for continued use in glycolysis and Krebs cycle.

Question 26

what happens to any spare electrons and protons at the electron transport chain?

Answer 26

they are collected by O2 and attached to O2 to produce water molecules.

Question 27

why is oxygen so significant in the electron transport chain?

Answer 27

if it doesn’t collect those spare electrons and electrons it will cause disasterous reactions in the cell to happen, and cell will die. so basically the cell will die without O2.

Question 28

inputs for electron transport chain?

Answer 28

6O2 + 12H+
26 OR 28 ADP + 26 OR 28 PI
10 NADH
2 FADH2

Question 29

outputs for electron transport chain?

Answer 29

6H2O
26 OR 28 ATP
10 NAD+ + 10H+
2 FAD+ + 4H+

Question 30

how much ATP in total is produced from each original glucose molecule that is commited to aerobic cellular respiration?

Answer 30

combined with the 2 atp produced during glycolysis, and the 2 ATP from the krebs cycle, a total of 30 or 32 ATP can be produced from each original glucose molecule that is committed to aerobic cellular respiration

Question 31

what do enzymes do in cellular respiration

Answer 31

enzymes, with the help of their coenzyme assistants catalyse the reaction of cellular respiration to allow them to proceed at significantly higher and biologically relevant rates.

Question 32

what are the 3 key coenzymes and what do they do?

Answer 32

ATP, NAD+ and FAD. they are cycled between the unloaded (ADP, NAD+, FAD+ COA) and loaded (ATP, NADH, FADH2, ACETYL COA) enzymes as they help catalyse the reactions of cellular respiration.

Question 33

what do coenzymes do in reactions that need extra energy?

Answer 33

they are unloaded in reactions that need extra energy (donate their protons and electrons)

Question 34

what docoenzymes do in reactions that produce energy?

Answer 34

they become loaded in reactions that produce energy (accept protons and electrons)

Question 35

what does the unloading and loading of coenzymes mean?

Answer 35

it means that they will always be efficiently recyled.