Cellular Respiration Flashcards
What is ATP?
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
What is aerobic respiration?
Involves the use of O2
C6H1206 + 02 = CO2 + H2O + ATP
What is ADP?
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
What are the 4 stages of respiration?
Glycolysis
Link reaction
Kreb cycle
Oxidative phosphorylation
What is glycolysis?
Splitting of 1 molecule of glucose into 2 pyruvate molecules
Occurs in the cytoplasm
What is oxidation and reduction? ( oil rig)
Oxidation is losing an electron
Reduction is gaining an electron
What are co enzymes?
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
Name the 2 co enzymes used in respiration?
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
What happens in the glycolysis stage?
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
What products go in and out of glycolysis?
In: 1 glucose, 2 NAD, 2ATP
Out: 2 pyruvate, 2 reduced NAD( NADH + H+), 4 ATP
Net gain: 2 ATP and 2 NADH + H+
What is the link reaction?
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
What goes in and out of link reaction?
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
What happens in the Kreb cycle?
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
For each citrate compound what is made?
2 CO2
3 NAD are reduced
1 FAD is reduced
1 ATP made directly
Everything is doubled so what goes in and out of Kreb cycle?
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
What is the running total from glycolysis, link and Kreb cycle?
6 CO2
4 ATPS made directly
10 reduced NAD
2 reduced FAD
What happens in the electron transport system?
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
What is the energy produced in the electron transport chain used for?
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
What is the final electron acceptor?
Oxygen
What is formed in CHEMIOSMOSIS ?
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
List the stages and amount of ATP produced in total.
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)
