Post on 24-Feb-2016
description
transcript
Overall Photosynthesis Reaction
6CO2 + 6H2O + energy C6H12O6 + 6O2
24 C-O bonds+
12 H-O bonds
36 covalent bonds
7 C-O bonds+
5 C-C bonds+
7 C-H bonds+
5 H-O bonds+
12 O-O bonds
36 covalent bonds
Overall Respiration ReactionC6H12O6 + 6O2 6CO2 + 6H2O + energy
24 C-O bonds+
12 H-O bonds
36 covalent bonds
7 C-O bonds+
5 C-C bonds+
7 C-H bonds+
5 H-O bonds+
12 O-O bonds
36 covalent bonds
C
C
Basis of photosynthesis:Light energy is used to transform C-O and H-O bonds into C-C and H-C bonds + Energy
C
O
+ Energy
Basis of respiration:Energy is liberated by transforming C-C and C-H bonds into C-O and H-O bonds
+ +
C
C
+ +
Increased potential energy
Decreased potential energy
H
C
H
C
H
O
C
O
H
O
Energy storage compounds
Energy carrier compounds
Fig. 8-8, p. 129
products haveless energy than
reactant did
Free
ene
rgy
substrate
substrates
Progress of reaction
products havemore energy than
reactants did
A + B
C + D
Free
ene
rgy
Uphill and downhill reactions.Only the downhill reaction will go forward spontaneously.Uphill reactions require an input of free energy from some other source.
Any uphill reaction needs to be combined with a downhill reaction to provide the energy needed.
ATPATP + H2O ADP + Pi + energy ADP + Pi + energy ATP + H2O
ATP is ideally suited as energy currency1. The amount of energy released is twice as
much as is needed to drive most cellular reactions.
2. ATP does not cross the cell membrane and is short lived.
3. The third phosphate bond of ATP is weak, unstable, breaks easily.
Fig. 8-9, p. 130
Proteins can bind ATP Most proteins (enzymes) that catalyze uphill
reactions bind ATP and use its energy.
ATP
C D+
Enzyme ATP-binding domain
Enzyme ATP-binding domainATP
ADP + Pi
Fig. 8-10, p. 131
adenine
adenine
ribose
ribose ribose
nicotin-amide
ribose
nicotin-amide
+
The oxidation of nicotinamide adenine dinucleotide by oxygen
The NADH loses one H and one chemical bond between H and C, which represents two electrons. The electrons may be transferred to a series of compounds before they reach oxygen.
NADH and NADPH
• NADH is used predominantly to make ATP during respiration
• NADPH is predominantly used during photosynthesis (formation of energy storage compounds)
Respiration Chapter 9
Overall Respiration ReactionC6H12O6 + 6O2 6CO2 + 6H2O + energy
24 C-O bonds+
12 H-O bonds
36 covalent bonds
7 C-O bonds+
5 C-C bonds+
7 C-H bonds+
5 H-O bonds+
12 O-O bonds
36 covalent bonds
Fig. 9-1, p. 135
Most of the glucose in a plant is stored as starch (see section on photosynthesis). Starch is a polymer of glucose. Before glucose can be respired, it needs to be produced from starch via hydrolysis. This enzymatic process does not require any energy input and is known as digestion.
DIGESTION
Stages in the Respiration of glucose
• Glycolysis (does not require O2)
• TCA cycle
(require O2)• Electron transport chain
Fig. 9-5, p. 138
ATP2
ATP2
ATP34
(net)
2 pyruvate
2 CO2
4 CO2TCACycle
6 NADH
2 FADH2
2 NADH
2 NADH
energyInput(ATP)
Mitochondrion
Cytoplasm
Electron transport chainphosphorylation
Glycolysis
glucose
water
oxygen
Overview of respiration steps
Locations of respiration stages in the plant cell
NUCLEUS
MITOCHONDRIUM
CHLOROPLASTCHLOROPLAST
CHLOROPLAST CHLOROPLAST
MITOCHONDRIUM
MITOCHONDRIUM
MITOCHONDRIUM
CYTOSOL
Notes: 1) cytosol is the same as cytoplasm 2) not all of the plant cell structures and organelles are shown 3) Digestion is by some authors considered as part of the respiration process
Cell wall
Glycolysis
TCA cycle
Electron transport chain
Digestion
Stages in Respiration
• Glycolysis
• TCA cycle
• Electron transport chain
glucose
glucose 6-phosphate
fructose 6-phosphate
ENERGY-REQUIRINGSTEPS OF GLYCOLYSIS:
2 ATP invested
fructose 1,6-bisphosphate
Fig. 9-3a, p. 137
No need to memorize intermediates
Fig. 9-3b, p. 137
2 NADH
2 ATP
2 ATP2 ADP
ENERGY-RELEASINGSTEPS OF GLYCOLYSIS:
phosphorylation,2 ATP produced
phosphorylation,2 ATP produced
2
2 NAD+
2 Pi
dihydroxyacetonephosphate
glyceraldehyde 3-phosphate
2
2
2
2
2
1,3-bisphosphoglycerate
3-phosphoglycerate
PEP
pyruvate
(to TCA cycle)
2-phosphoglycerate
Net energy yield2 ATP
2 NADH
H2O
2 ADP
No need to memorize intermediates
Overall Glycolysis ReactionGlucose + 2 ADP + 2 Pi + 2 NAD+ 2 pyruvate + 2 ATP + 2 NADH
+ 2H+
CC
C CC
H O
C O H
H
H
OH
HO
O H
HH
O H
Glucose
H
H
C CO
CO
OH
H
HH
Pyruvate
Glucose + 2 ADP + 2 Pi + 2 NAD+ 2 pyruvate + 2 ATP + 2 NADH + 2H+
C CO
CO
OH
H
HH
Pyruvate
7 C-O bonds+
5 C-C bonds+
7 C-H bonds+
5 H-O bonds
24 covalent bonds
10 C-O bonds+
4 C-C bonds+
6 C-H bonds+
2 H-O bonds
22 covalent bonds
CC
C CC
H O
C O H
H
H
OH
HO
O H
HH
O H
Glucose
H
H
Glucose + 2 ADP + 2 Pi + 2 NAD+ 2 pyruvate + 2 ATP + 2 NADH + 2H+
C CO
CO
OH
H
HH
Pyruvate
7 C-O bonds+
5 C-C bonds+
7 C-H bonds+
5 H-O bonds
24 covalent bonds
10 C-O bonds+
4 C-C bonds+
6 C-H bonds+
2 H-O bonds
22 covalent bonds and…..
CC
C CC
H O
C O H
H
H
OH
HO
O H
HH
O H
Glucose
H
H
Fig. 8-10, p. 131
adenine
adenine
ribose
ribose ribose
nicotin-amide
ribose
nicotin-amide
+
The oxidation of nicotinamide adenine dinucleotide by oxygen
NADH loses one H and one chemical bond between H and C, which represents two electrons. The electrons may be transferred to a series of compounds before they reach oxygen (see electron transport chain).
The inverse is also possible: reduction of nicotinamide adenine dinucleotide
NAD+ can gain an electron pair (of high energy) and together with a H+ can form the C-H bond again.
2e- H+