LESSON 3c: Photosynthesis Flashcards
1
Q
-get their energy from “eating others”
-make energy through respiration
A
Heterotrophs (Animals)
2
Q
- produce their own energy (from “self”)
- convert energy of sunlight
- build organic molecules (CHO) from CO2
- make energy & synthesize sugars through
photosynthesis
A
Autotrophs (Plants)
3
Q
making energy & organic molecules from ingesting organic molecules
A
Heterotrophs
4
Q
(Give the formula) glucose + oxygen —> carbon dioxide + water + energy
A
C6H12O6 + 6O2 —> 6CO2 + 6H2O + ATP
5
Q
making energy & organic molecules from light energy
A
Autotrophs
6
Q
(Give the formula) carbon + water + energy – >glucose + oxygen
A
6CO2 + 6H2O + Light Energy —> C6H12O6 + 6O2
7
Q
-collect light energy
-transform it into chemical energy
-store light energy
-need to get building block atoms
from the environment
- produce all organic molecules
needed for growth
A
Plants
8
Q
Obtain Sunlight
A
Leaves
9
Q
Leaves
A
Solar Collectors
10
Q
Obtain CO2
A
Stomates
11
Q
Stomates for _________
A
Gas Exchange
12
Q
Obtain water
A
roots
13
Q
Nutrients that is obtained by roots
A
-Nitrogen
-Phosphorus
-Potassium
-Sulfur
-Magnesium
-Iron
14
Q
absorb light and CO2 and make energy & sugar
A
Chloroplasts
15
Q
Chloroplast contains ___________
A
Chlorophyll
16
Q
Parts of Chloroplasts
A
-Double membrane
-Stroma
-Thylakoid sacs
-Grana Stacks
17
Q
fluid-filled interior
A
Stroma
18
Q
Thylakoid membrane contains
A
-chlorophyll molecules
-electron transport chain
-ATP synthase
19
Q
H+ gradient built up within
thylakoid sac
A
ATP synthase
20
Q
Types of Light Reactions
A
-light-dependent reactions
-energy conversion reactions
20
Q
-convert solar energy to chemical energy
-ATP & NADPH
A
energy conversion reactions
20
Q
-uses chemical energy (ATP & NADPH) to reduce CO2 & synthesize C6H12O6
A
sugar building reactions
21
Q
Calvin Cycle include _____________
A
-light-independent reactions
-sugar building reactions
22
Q
Light Reactions like in cellular respiration
A
Electron Transport Chain
22
Light Reaction electron Acceptors
NADPH
23
Mitochondria transfer chemical energy from food molecules into ________________________
chemical energy of ATP
24
ETC of Respiration use electron Carrier ___________
NADH
25
Chloroplasts transform________ into chemical energy of ATP
light energy
26
ETC of photosynthesis used electron carrier _____
NADPH
27
The ATP that "jack" built Photosynthesis
Sunlight
28
To do photosynthesis/respiration, sunlight/breakdown of Glucose allows the ff.
§ moves the electrons
§ runs the pump
§ pumps the protons
§ builds the gradient
§ drives the flow of protons
through ATP synthase
§ bonds Pi to ADP
§ generates the ATP
29
The ATP that "jack" built respiration is
Breakdown of Glucose (C6H12O2)
30
- embedded in thylakoid membrane
- arranged in a “photosystem”
- structure-function relationship
Chlorophylls & other pigments
31
Chlorophylls & other pigments is arrange in a _________
Photosystem
32
Shorter wavelength--> longer wavelength]
and
Higher energy to lower energy
-Gamma Rays > X-ray > UV > Infrared > Microwaves > Radio waves
33
Photosynthesis gets energy by ___________
absorbing
wavelengths of light
34
absorbs best in red & blue wavelengths & least in green
chlorophyll a
35
accessory pigments with different structures absorb light of different wavelengths
-chlorophyll b,
-carotenoids,
-xanthophylls
36
- collections of chlorophyll molecules
-act as light-gathering molecules
2 photosystems in thylakoid membrane
37
-chlorophyll a
- P680 = absorbs 680nm
wavelength red light
Photosystem II
38
-chlorophyll b
-P700 = absorbs 700nm
wavelength red light
Photosystem I
39
ETC uses light energy to produce
ATP & NADPH
40
PS II absorbs light
- excited electron passes from chlorophyll to
“primary electron acceptor”
- need to replace electron in chlorophyll
- enzyme extracts electrons from H2O & supplies them to chlorophyll
41
Where did the O2 come from?
radioactive tracer = O18
42
Proved O2 came from H2O not CO2 =________
plants split H2O
43
Light reactions elevate
electrons in 2 steps (PS II & PS I)
Noncyclic Phosphorylation
44
PS II generates
energy as________
ATP
45
PS I generates
reducing power as ________
NADPH
46
-If PS I can’t pass electron to
NADP…it cycles back to PS II &
makes more ATP, but no NADPH
-coordinates light reactions to
Calvin cycle
-Calvin cycle uses more ATP than
NADPH
Cyclic Phosphorylation
47
18 ATP + 12 NADPH ---> _________
1 C6H12O6
48
Light reactions converts solar energy to ___________________
Chemical energy
49
____has very little chemical energy
CO2
50
__________ contains a lot of chemical energy
C6H12O6
51
-proceeds in many small
uphill steps
-each catalyzed by specific enzyme
-using energy stored in ATP & NADPH
Reduction of CO2 ----> C6H12O6
52
Calvin cycle in plants happens in ______
Chloroplast stroma
53
Calvin cycle need products of light reactions to drive synthesis reactions. What are the products?
-ATP
-NADPH
54
-end product of Calvin cycle
- energy rich 3 carbon sugar
-“C3 photosynthesis”
Glyceraldehyde-3-P (G-3-P)
55
G-3-P can be convert to ____________
-glucose--> carbohydrates
-Lipids
-Amino acids
-nucleic acids
56
-Enzyme which fixes carbon from air
-the most important enzyme in the world
-definitely the most abundant
RUBISCO
57
RUBISCO
ribulose bisphosphate carboxylase
58
3 turns of Calvin cycle (Plants) =_____
1 G3P
59
3 CO2 --> _______
1 G3P (3C)
60
6 turns of Calvin cycle =
1 C6H12O6 (6C)
61
6 CO2 -->_____
1 C6H12O6 (6C)
62
18 ATP + 12 NADPH --> ________
1 C6H12O6
63
any ATP left over from light reactions will be used __________ by the cell
elsewhere
64
-produced ATP
-produced NADPH
-consumed H2O
-produced O2 as byproduct
Light Reactions
65
- consumed CO2
- produced G3P (sugar)
- regenerated ADP
- regenerated NADP
Calvin Cycle
66
During Photosynthesis, light reactions need light from _________ and H2O from _________
-Sun
-ground
67
During Photosynthesis, calvin cycle needs CO2 from __________
Air
68
CO2 in
Calvin Cycle
69
O2 out
waste from Light reaction
69
H2O out
Light reactions
70
how plants control water loss from leaves?
-stomates close to conserve water
71
When guard cell gain H2O, stomates _____
open
72
when guard cells lose H2O, stomates _____
close
73
Closed stomates leads to?
-O2 builds up --> from light reactions
- CO2 is depleted --> in Calvin cycle (which cause problems)
74
Rubisco in Calvin Cycle
-carbon fixation enzyme (Photosynthesis)
-when O2 concentration is high (Photorespiration)
75
carbon fixation enzyme
-normally bonds C to RuBP
-reduction of RuBP
-building sugars
76
when O2 concentration is high
-Rubisco bonds O to RuBP
-O2 is alternative substrate
-oxidation of RuBP
-breakdown sugars
77
-short circuit of Calvin cycle
-loss of carbons to CO2
-reduces production of photosynthesis
-if photorespiration could be reduced, plant would become 50% more efficient
Oxidation of RuBP
78
-physically separate carbon fixation from actual Calvin cycle
- different enzyme to capture CO2
-PEP carboxylase stores carbon in 4C
compounds
-different leaf structure
C4 Plants
79
- separate carbon fixation from actual Calvin cycle by time of day
- fix carbon (capture CO2) during night
- store carbon in organic acids
- perform Calvin cycle during day
CAM Plants
80
C4 Plants: 1st step before Calvin cycle,
fix carbon with enzyme
______________
PEP carboxylase
81
PEP carboxylase is store as ______________
4C Compound
82
Example of C4 Plants
Sugar Cane, Corn and other grasses
83
-higher affinity for CO2 than O2 (better than Rubisco)
-fixes CO2 in 4C compounds
-regenerates CO2 in inner cells for Rubisco
PEP carboxylase enzyme
84
phosphoenolpyruvate (3C) + CO2-->____________
oxaloacetate (4C)
85
Separate reactions in different cells
-light reactions
-carbon fixation
-Calvin cycle
86
C4 Photosynthesis: -light reaction &
carbon fixation
-pumps CO2 to inner cells
-keeps O2 away from inner cells
Outer cells
87
C4 Photosynthesis: -Calvin cycle
-glucose to veins
Inner Cells
88
CAM Plants
Crassulacean Acid Metabolism
89
CAM Plants: Different adaptation to hot, dry climates
-separate carbon fixation from Calvin cycle by time
-at night, open stomates & fix
carbon in “storage” compounds
-in day, close stomates & release CO2 from
“storage” compounds to Calvin cycle
90
Organic Acids stored in stomates of CAM Plants as mentioned in the PPT
-Malic Acids
-Isocitric Acid
91
examples of CAM plants
-Succulent
-some cacti
-pineapple
92
C4 Plants VS. CAM Plants
-C4 plants
separate 2 steps of C fixation anatomically in 2 different cells
-CAM plants
separate 2 steps of C fixation temporally at 2 different times
93
-most plants
-fix carbon in Calvin cycle (Attach CO2 to RuBP)
-Enzyme: Rubisco
-Most Energy efficient method
-losses water through photorespiration
C3 Plants
94
-Tropical grasses (corn, sugar cane)
-Fix carbon in cytoplasm (attach CO2 to PEP
-Enzyme: PEP-ase
-1/2 way between C3 and CAM
-Losses less water
C4 Plants
95
-Succulents, pineapples, agave
-fix carbon at night only, fix it to organic molecules
-Enzyme: PEP-ase
-Best Water Conservation
-Loses least water
CAM Plants
96
Possibly evolutionary baggage
-Rubisco evolved in high CO2 atmosphere
(there wasn’t strong selection against active site of Rubisco accepting both CO2 & O2)
