Cellular Respiration

Question 0

What is ATP?

Answer 0

Energy from glucose is used to make ATP- carries energy to cells that need it.
1 pentose sugar, 3 phosphate and 1 nucleotide base.
Energy held in the phosphate bonds - energy released when these bonds are broken- make ADP

Question 1

What is aerobic respiration?

Answer 1

Involves the use of O2

C6H1206 + 02 = CO2 + H2O + ATP

Question 2

What is ADP?

Answer 2

Adenosine diphosphate- energy released when ATP breaks phos bond to make ADP
ATP fully charged battery
ADP partially charged
30.6 KJ released for every ATP, ADP+P

Question 3

What are the 4 stages of respiration?

Answer 3

Glycolysis
Link reaction
Kreb cycle
Oxidative phosphorylation

Question 4

What is glycolysis?

Answer 4

Splitting of 1 molecule of glucose into 2 pyruvate molecules

Occurs in the cytoplasm

Question 5

What is oxidation and reduction? ( oil rig)

Answer 5

Oxidation is losing an electron

Reduction is gaining an electron

Question 6

What are co enzymes?

Answer 6

Transfer a chemical group from 1 molecule to another- speeds up process
In respiration these co E remove electrons or H atoms. These are transferred to electron/ hydrogen carriers then passed to O2 to form H2O at end of respiration

Question 7

Name the 2 co enzymes used in respiration?

Answer 7

NAD (nicotinamide adenine dinucleotide)
FAD ( flavin adenine dinucleotide) 
See the as taxi drivers - picking up hydrogen
Reduced NAD picks up H+ = NADH
Oxidised- lose H+ = NAD

Question 8

What happens in the glycolysis stage?

Answer 8

Phosphorylation- glucose is phosphorylated by adding 2 phosphates from 2 molecules of ATP. 6 C sugar split into 2 3 C sugars (triose phosphate)Oxidation- these 2 3C sugars lose H+ = 2 molecules of pyruvate. 2 NAD collect H+ to form 2 NADH. 4 ATP produced but only 2 gained as 2 needed to start the process

Question 9

What products go in and out of glycolysis?

Answer 9

In: 1 glucose, 2 NAD, 2ATP
Out: 2 pyruvate, 2 reduced NAD( NADH + H+), 4 ATP
Net gain: 2 ATP and 2 NADH + H+

Question 10

What is the link reaction?

Answer 10

It links glycolysis to Kreb cycle ( movement into matrix)
Pyruvic acid loses a carbon- breathed out as co2
Hydrogen that was attached to carbon is picked up by NAD
Co enzyme A joins the 2 carbon molecule to form acetyl co enzyme A

Question 11

What goes in and out of link reaction?

Answer 11

In: 2 pyruvate and 2 coA and 2 NAD

Out: 2 acetyl co A, 2 CO2 and 2 reduced NAD ( 2NADH + H)

NO ATP made directly

Question 12

What happens in the Kreb cycle?

Answer 12

Each acetyl co A(2C) combines with oxaloacetate to make citric acid(6C)- coA goes back into cycle to be used again
Citrate converted to alpha ketoglutaric acid(5C)- losing co2 and H
5C molecule converted to succinc acid then malic acid then oxaloacetatic acid (4C). Co2 and hydrogen lost and ATP made

Question 13

For each citrate compound what is made?

Answer 13

2 CO2
3 NAD are reduced
1 FAD is reduced
1 ATP made directly

Question 14

Everything is doubled so what goes in and out of Kreb cycle?

Answer 14

IN: 2 acetyl co A, 6 NAD, 2FAD, 2 ATP + P

Out: 2 oxaloacetate, 4 CO2, 6 reduced NAD (6 NADH), 2 reduced FAD ( 2 FADH2), 2 ATP

Question 15

What is the running total from glycolysis, link and Kreb cycle?

Answer 15

6 CO2
4 ATPS made directly
10 reduced NAD
2 reduced FAD

Question 16

What happens in the electron transport system?

Answer 16

H atoms are released from reduced NAD and FAD- form H ions and electrons
Electrons move along chain made of electron carriers losing energy at each carrier.
Each carrier lower energy level so energy released at each one

Question 17

What is the energy produced in the electron transport chain used for?

Answer 17

Used to pump H ions from matrix into the intermembrane space where conc of ions is now higher.
H ions brought back to matrix through ATP synthase which adds a phosphate to ADP to make ATP = CHEMIOSMOSIS
H ions, electrons and oxygen combine to form water

Question 18

What is the final electron acceptor?

Answer 18

Oxygen

Question 19

What is formed in CHEMIOSMOSIS ?

Answer 19

For every reduced NAD feeding H into the chain 2.5 ATP made

For every reduced FAD feeding H into chain 1.5 ATP made

Question 20

List the stages and amount of ATP produced in total.

Answer 20

Glycolysis- 2 ATP directly, 2 Red NAD = 2x2.5=5
Link reaction(x2)- 2 Red NAD = 2x2.5= 5
Kreb(x2)- 2 ATP directly
Kreb(x2)- 6 Red NAD= 6x2.5=15
Kreb(x2)- 2 Red FAD= 2x 1.5= 3.   TOTAL ATP = 32 (1 mol glucose)