Photosynthesis Flashcards
1
Q
Two orders
A
- More orderly
- Less orderly
2
Q
- highly ordered, highly structured system
- accomplished by putting energy into a living system
A
more orderly
3
Q
- increase of entropy
- accomplished through energy transfers
A
less orderly
4
Q
measure of randomness or disorder in a system
A
entropy
5
Q
Two (2) methods sunlight maintains the state of low entropy
A
- Directly
- Indirectly
6
Q
Method sunlight maintains the state of low entropy:
Directly
A
photosynthesis
7
Q
Methods sunlight maintains the state of low entropy:
Indirectly
A
respiration
8
Q
basis for a major, fundamental distinction in the types of organisms
A
- photosynthesis
- respiration
9
Q
organisms that gather energy directly from light and use it to assimilate small inorganic molecules into their own tissues
A
Photoautotrophs
10
Q
Ex. of photoautotrophs
A
- all green plants
- cyanobacteria
- few bacteria capable of photosynthesis
11
Q
organisms take in organic molecules and respire them, obtaining energy available in them
A
Heterotrophs
12
Q
Ex. of heterotrophs
A
- all animals
- completely parasitic plants
- fungi
- non-photosynthetic prokaryotes
13
Q
plants that are not capable of photosynthesis and obtain all nutrients and water from a host plant
A
Holoparasitic plants
14
Q
specialized, modified root of parasitic plants that penetrates into a host plant and functions to acquire necessary nutrients from the host plant they attached themselves to
A
haustorial root
15
Q
Ex. of holoparasites
A
Cuscuta
16
Q
Difference between Photoautotrophs and Heterotrophs:
Source of energy
A
Photoautotrophs:
sunlight
Heterotrophs:
food: carbohydrates, proteins, fats
17
Q
Difference between Photoautotrophs and Heterotrophs:
Source of building material
A
Photoautotrophs:
carbon dioxide
Heterotrophs:
food
18
Q
Difference between Photoautotrophs and Heterotrophs:
Organisms
A
Photoautotrophs:
1. photosynthetic plants and bacteria
2. algae
3. cyanobacteria
Heterotrophs:
1. animals
2. protozoa
3. non-photosynthetic parts of ordinary plants
4. completely parasitic plants
5. most bacteria
6. fungi
19
Q
process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar
A
Photosynthesis
20
Q
what drives endergonic reactions in photosynthesis
A
Adenosine Triphosphate (ATP)
21
Q
carries new bonding orbitals filled by electrons to the reaction
A
NADPH
22
Q
Energy enters the biological world through _____
A
photosynthesis
23
Q
two major pigments involved in photosynthesis
A
- Chlorophyll A
- Chlorophyll B
24
Q
absorbs violet and orange light the most.
A
chlorophyll a
25
absorbs mostly blue and yellow light.
chlorophyll b
26
Chlorophyll a and b also absorb light of other wavelengths with ___ intensity.
less
27
Cons of energy carriers
- large molecules
- not very mobile
- too energetic
28
Three (3) methods of synthesizing ATP
1. Photophosphorylation
2. Substrate-level phosphorylation
3. Oxidative phosphorylation
29
Energy source:
Photophosphorylation
sunlight
30
Energy source:
Substrate-level photophosphorylation
reactions not involving oxygen
31
Energy source:
Oxidative photophosphorylation
oxidations with oxygens
32
Site:
Photophosphorylation
chloroplast
33
Site:
Substrate-level photophosphorylation
cytosol
34
Site:
Oxidative photophosphorylation
mitochondria
35
potential or power of any substance to reduce another substance that can be either by addition or removal of hydrogen or by loss or gain of electrons
reducing power
36
- chemical reaction in which electrons are transferred between two reactants participating in it
- transfer of electrons can be identified by observing the changes in the oxidation states of the reacting species
oxidation-reduction reactions
37
an atom loses electrons (e-), increasing positive charge
oxidation
38
an atom gains an electron (e-), reducing its positive charge
reduction
39
When the oxidation state increases, means electrons are removed, thus, the substance is ____
oxidized
40
substance that is being oxidized is called ____
reducing agent
41
When the oxidation state decreases, means electrons are added, thus the substance is ____
reduced
42
substance that is being reduced is called the ____
oxidizing agent
43
The oxidation state of an atom in any pure element is ____
0 (zero)
44
The oxidation state of hydrogen is ____ when in a regular compound
+1
45
The oxidation state of hydrogen is ____ when bonded to a metal
-1
46
Oxygen usually has an oxidation number of ____
-2
47
most highly oxidized forms of carbon and hydrogen
- carbon dioxide
- water
48
Compounds in the environment are predominantly in the ____ _____ because of our oxygen-rich atmosphere
oxidized state
49
Most compounds in organisms are in the ____ ____
reduced state
50
oxidize the material they interact with
oxidizing agents
51
Ex. of oxidizing agents
- NAD+
- NADP+
52
Two strong reducing agents
- NADH
- NADPH
53
have a powerful tendency to place electron onto other molecules, reducing those molecules and becoming oxidized themselves
reducing agents
54
tendency to accept or donate electrons varies greatly
redox potential
55
involved in an oxidation reaction of cellular respiration
Nicotinamide Adenine Dinucleotide (NAD+)
56
involved in an oxidation reaction of photosynthesis
Nicotinamide Adenine Dinucleotide Phosphate (NADP+)
57
What is formed after NAD+ and NADP+ take electrons away from other molecules (gaining of electrons)
- NADH
- NADPH
58
proteins that contain heme as their prosthetic group
Cytochromes
59
Biological function of cytochromes
electron transport
60
Cytochromes carries electrons and cycles between the ___ and ___ oxidation states
- +2
- +3
61
Where are cytochromes localized
compartment between the inner and outer mitochondrial membrane
62
Other electron carriers
1. Cytochromes
2. Plastoquinone
3. Plastocyanin
63
- associated with Photosystem II
- mobile electron carrier through the membrane of the thylakoid
- hydrophobic; allows them to dissolve easily into the lipid component of chloroplast membrane
Plastoquinone
64
Plastoquinone is reduced; accepts two protons (H+) from the stromal matrix of the chloroplast, coupled to two electrons (e-) from photosystem II, forming ____
plastoquinol
65
Plastoquinone being hydrophobic allows them to ___ ___ into the lipid component of ___ ___
- dissolve easily
- chloroplast membrane
66
- a copper-containing protein that mediates electron-transfer
- acts as a redox protein in oxygenic photosynthesis,
- carry electrons from cytochrome f to a protein in photosystem I
Plastocyanin
67
Loosely associated with chloroplast membranes Plastocyanin transport route involves two steps:
1. import into the chloroplasts
2. subsequent routing over the thylakoid membrane into the lumen
68
Why are carbon dioxide and water used?
- abundant and cheap
- diffuse into plants automatically
- stable and contain little chemical energy
- nontoxic
69
Carbon atom in carbon dioxide is at the ____ oxidation state during photosynthesis
+4
70
Carbon atoms in carbohydrate are at ___
+0
71
Electron source
water
72
energy source
light
73
Light-dependent reactions
thylakoid reactions
74
process that creates the intermediates ATP and NADPH
photosynthesis
75
stroma reactions
dark reactions
76
ATP and NADPH interact with carbon dioxide and actually produce ____
carbohydrate
77
one small segment of the electromagnetic radiation spectrum (gamma rays, X-rays, ultraviolet light, infrared light, microwaves, and radio waves, in addition to visible light.)
Light
78
What are included in the electromagnetic radiation spectrum
1. gamma rays
2. x-rays
3. ultraviolet light
4. visible light
5. infrared light
6. microwaves
7. radio waves
79
- energy that comes from a source and travels through space at the speed of light
- has an electric field and a magnetic field associated with it, and has wave-like properties
- also called “electromagnetic waves”
Radiation
80
Radiation can be thought of and treated physically either:
1. set of particles- Quanta also called Photon
2. set of waves
81
have relatively large amounts of energy in each quantum
short wavelengths
82
short wavelengths
- cosmic rays
- gamma rays
- ultraviolet rays
83
- low energy
- lower frequency
long wavelengths
84
long wavelengths
- infrared
- microwaves
- radar
- radio waves
85
Most of us see all wavelengths from ___ to ___
760nm to 390nm
86
760 nm color
red
87
390 nm color
violet
88
All animals see in the range from ___ to ___, which is also the radiation that plants use for photosynthesis
350 to 760 nm
89
- Any material that absorbs certain wavelengths specifically and therefore has distinctive color
- Substances that absorb light as part of their biological function
pigment
90
pigment of our skin
melanin
91
- Transfer absorbed light energy to electrons that then enter chemical reactions
- The pigment should at least absorb high- energy radiation (ultraviolet light and gamma rays) instead of the fairly weak visible light
Photosynthetic pigments
92
In general, plants only capture about ____ of the energy available in the electromagnetic radiation that strikes them.
5%
93
an integral membrane protein complex that uses light energy to catalyze the transfer of electrons across the thylakoid membrane from plastocyanin to ferredoxin
phtosystem 1
94
Location of Photosystem 1:
Plants and Algae
thylakoid membrane
95
Location of Photosystem 1:
Photosynthetic bacteria
cell membrane
96
An energy diagram for electron transfer in the "light reactions" of plant photosynthesis.
z-scheme
97
A small protein with an active site consisting of two iron atoms bound to two sulfur atoms
ferredoxin
98
The pair of chlorophylls of the photosystem I reaction center is given the special name ___ because they absorb red light of 700 nm most efficiently.
P700
99
an electron acceptor and is going to be reduced to NADP or NADPH
NADP+
100
- donates electron to Photosystem 1
- extracts electron from water molecules
Photosystem II
101
Process of Photosystem II:
1. light absorption
2. high electron energy
3. electron transport chain
4. water molecule electron extraction
102
Location of Photosystem II
inside the chloroplast in the thylakoid membrane
103
Photosystem II:
1. Light energy is absorbed by pigment molecules and chlorophylls that then transfer that energy into the ___.
P680
104
Photosystem II:
2. The photons from the light energy excite an electron putting it into a _____.
high-energy state
105
Photosystem II:
3. What does the electron in the high-energy state undergo to go back to a low-energy state?
Electron Transport Chain
106
Photosystem II:
4. The electron will then be donated to _____
Photosystem I
107
Photosystem II:
5. Once the P680 loses the electron in grabs unto the nearest ____ ____ and takes away its electron.
water molecule
108
Photosystem II:
6. The water molecule falls apart into ___ and ___ ___
oxygen and hydrogen ions
109
gets new electrons from water molecules
phaeophytin
110
donates electron to plastoquinone
Q
111
donates electron to cytochrome b6/f complex
plastoquinone
112
donates electron to plastocyanin
cytochrome b6/f complex
113
donates electron to the chlorophyll a of the Photosystem I reaction center
plastocyanin
114
- energy currency of cells or living organisms
- required for various cellular activities such as active transport of ions, muscle contraction, cell signaling, synthesis of biomolecules
- primarily synthesized in the cellular respiration process
Adenosine Triphosphate (ATP)
115
- product of the first stage of photosynthesis
- used to help fuel the reactions that take place in the second stage of photosynthesis
Nicotinamide Adenine Dinucleotide Phosphate Hydrogen (NADPH)
116
third, and final, biological pathway responsible for the production of ATP from an inorganic phosphate and an ADP molecule via oxidative phosphorylation
Chemiosmotic phosphorylation
117
any of the membranous disks of lamellae within plant chloroplasts that are composed of protein and lipid and are the sites of the photochemical reactions of photosynthesis
thylakoid
118
stack of thylakoid
grana (singular: granum)
119
thylakoids that lie between grana
frets
120
liquid surrounding the thylakoid system
stroma
121
continuous aqueous phase enclosed by the thylakoid membrane.
thylakoid lumen
122
enzyme complex that catalyzes the formation of ATP from ADP and inorganic phosphate
ATP Synthetase
123
The ATP synthetase of chloroplasts is known specifically as the _____ ____
CF0 - CF1 complex
124
Two (2) types of electron transport
1. noncyclic electron transport
2. cyclic electron transport
125
electrons flow through the Z scheme from water to nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)
noncyclic electron transport
126
Electrons flow from P700 to plastoquinone, which carries a proton to the lumen and returns the electron to P700
cyclic electron transport
127
where conversion of carbon dioxide to carbohydrate occurs
stroma reactions
128
other names of stroma reactions
- Calvin/Benson cycle
- c3 cycle
129
overall purpose of the Calvin/Benson cycle
convert carbon dioxide from the atmosphere into carbohydrates
130
what does the Calvin/Benson cycle reactions use to convert CO2 to carbohydrates
ATP and NADPH produced by light reactions
131
The Stages of Calvin/Benson Cycle
1. Fixation
2. Reduction
3. Regeneration
132
The enzyme RuBisCO incorporates carbon dioxide into an organic molecule, 3-PGA
fixation
133
The organic molecule is reduced using electrons supplied by NADPH
reduction
134
RuBP, the molecule that starts the cycle, is regenerated so that the cycle can continue
regeneration
135
one of the largest and most complex enzymes known—a giant complex of two kinds of protein subunits
RuBP carboxylase (RUBISCO)
136
set of life-sustaining chemical transformations within the plant cell
metabolism
137
breakdown of larger molecules
catabolism
138
synthesis of larger molecules
anabolism
139
- composed of 3-phosphoglyceraldehyde, water, nitrates, sulfates, and minerals
- basis of all animal metabolism
anabolic metabolism
140
Types of Storage Compounds
1. short-term storage
2. intermediate-term storage
3. long-term storage
141
- ATP and NADPH
- last only briefly
short-term storage
142
- simple sugar glucose and disaccharide sucrose
- last for week or months
intermediate-term storage
143
- starch and lipids
- lasts for years
long-term storage
144
anabolic synthesis of glucose
gluconeogenesis
145
Starch (storage)
- amylose
- amylopectin
146
structural
cellulose
147
- Unbranched Polymer of Glucose
- Has one end and synthesized slowly
- Digested more slowly
amylose
148
- Branched Polymer of Glucose
- Has thousands of enzymes simultaneously adding glucose
- Can be digested back to glucose monomers much more faster than amylose
amylopectin
149
- Digests the amylopectin portion of starch rapidly
- Makes glucose available to our bloodstream quickly
salivary amylase
150
polysaccharides are stored as ___ in animals
glycogen
151
polysaccharides are stored as ___ in plants
starch
152
where are starch located in plants
- chloroplasts
- amyloplasts
153
Most of the 3-phosphoglyceraldehyde is retained, converts it to glucose, and polymerized to starch
daylight
154
Chloroplasts are swollen because of large starch grains they contain
afternoon
155
Starch is depolymerized back to glucose
night
156
Three (3) important properties of light
1. Quality
2. Quantity
3. Duration
157
- refers to the wavelength and the colors composing the light which affects the growth of the plant
- factors are being manipulated by the planet refracting and reflecting certain types of waves and color varies by it's rotation and atmosphere.
Quality of sunlight
158
- refers to light intensity, brightness and availability of light, and is affected by several factors
- light is more available for photosynthesis during a clear day compared to a cloudy one as an example
Quantity of light
159
number of hours of light a plant needs per 24-hour period and allows the plant to make sufficient food to survive and grow which can be embedded to the plant making some varieties that need a specific time-span to be exposed to light
Duration of Light
160
major factor for a plant to absorb carbon dioxide
light
161
Photosynthesis is __ and __ on overcast days, but __ on brighter days
- slow and dull
- faster
162
The __ of photosynthesis is directly affected by the amount of light available
rate
163
reduce the water lost from the leaf
Cuticle
164
- contains no chloroplasts
- prevents water from getting out and stopping unwanted substances/organisms from getting in
Epidermis
165
most of the photosynthesis occurs in the leaf
Palisade Mesophyll Layer
166
contain a lot of chloroplasts to help them perform photosynthesis and are closely packed together to maximize light absorption
Palisade Cells
167
The cells are not as closely packed as the cells in the palisade mesophyll layer
Spongy Mesophyll Layer and air spaces
168
creates air spaces inside the leaf to enable gases to move in and out
Air Spaces
169
There are not as many chloroplasts in the spongy mesophyll cells as there are in the palisade mesophyll cell
Spongy mesophyll layer
170
holes found in leaves where it allows gases to diffuse in and out of the leaves
stoma
171
two highly specialized epidermis cells that forms stoma
guard cells
172
movement of gases in opposite directions
gas exchange
173
excellent for absorbing carbon dioxide but inefficient for conserving water
- Palisade parenchyma
- spongy mesophyll
174
Method of Minimizing Water
1. Keep their stomata closed so much of the time that they would starve
2. Reduce external surface by means of cylindrical leaves
175
evaporation of water from plants occurring at the leaves while their stomata are open for the passage of CO2 and O2 during photosynthesis
Transpiration
176
- wasteful pathway that competes with the Calvin cycle
- begins when rubisco acts on oxygen instead of carbon dioxide.
Photorespiration
177
occasionally binds to oxygen instead of carbon dioxide, acting as an oxygenase
RuBP carboxylase
178
molecules produced when RuBP carboxylase binds to oxygen instead of carbon dioxide
- one molecule of 3-phosphoglycerate
- one of phosphoglycolate
179
Where is phosphoglycolate transported
from the chloroplast to peroxisomes and mitochondria
180
Some of the phosphoglycolate is converted to useful amino acids
- glycine
- serine
181
much of the phosphoglycolate is broken down to
two molecules of carbon dioxide
182
Three main types of photosynthesis are C3, C4, and CAM (crassulacean acid metabolism)
1. C3 metabolism
2. C4 metabolism
3. Crassulacean acid metabolism (CAM)
183
- mechanism by which carbon dioxide is absorbed, transported through, and concentrated in a leaf, whereas oxygen is kept away from RuBP carboxylase
- occurs in leaves with Kranz anatomy
C4 metabolism
184
meaning wreath or ring in Germany
Kranz
185
C4 plants have little ____
photorespiration
186
Mesophyll contains an enzyme called ___ ___; has a high affinity for carbon dioxide.
PEP carboxylase
187
PEP carboxylase adds CO2 to PEP, producing a 4-carbon organic acid which is called ____, hence the name C4 metabolism.
Oxaloacetate
188
Oxaloacetate is reduced to ___ by a molecule of ____
- malate
- NADPH
189
Malate from throughout the mesophyll moves into the bundle sheath and breaks down into ____ by releasing carbon dioxide
pyruvate
190
This reaction is powerful enough to drive the formation of a new molecule of ____, so, the process results in the transport by malate of both carbon dioxide and reducing power
NADPH
191
Because NADPH is synthesized by this unusual method in bundle sheath cells, the bundle sheath chloroplasts primarily carry out ___ ___ ___, pumping protons and making ATP
cyclic electron transport
192
- Like any other carrier, malate must be shuttled back to its recharge site, the mesophyll.
- In the bundle sheath it is converted to (1)___ by the release of (2)___ ___;
- pyruvate moves back to the mesophyll and receives a phosphate group from ATP, which converts it to (3)___.
(1) pyruvate
(2) carbon dioxide
(3) PEP
193
Types of Carbon dioxide processing of C3, C4, and CAM Plants:
Ultimate carboxylase
C3 plants, C4 plants, CAM plants
- RuBP carboxylase
194
Types of Carbon dioxide processing of C3, C4, and CAM Plants:
Adjunct metabolism
C3 plants
- None
C4 plants, CAM plants
- CO2 transfer
195
Types of Carbon dioxide processing of C3, C4, and CAM Plants:
Adjunct carboxylase
C3 plants
- none
C4 plants, CAM plants
- PEP carboxylase
196
Types of Carbon dioxide processing of C3, C4, and CAM Plants:
Photorespiration
C3 plants
- high
C4 plants
- low
CAM plants
- moderate
197
Types of Carbon dioxide processing of C3, C4, and CAM Plants:
Stomata open
C3 plants, C4 plants
- day
CAM plants
- night
198
Under warm, dry conditions, ___ ___ has a strong selective advantage over ___ ___: Much less water is lost during carbon dioxide absorption
- C4 metabolism
- C3 metabolism
199
- second metabolic adaptation that improves the conservation of water while permitting photosynthesis
- allows a plant to photosynthesize during the day, but only exchange gases at night.
Crassulacean Acid Metabolism(CAM) is a
199
It is so named because it was first discovered in those members of the family ___
Crassulaceae
200
A CAM plant leaves its stomata open at ___, allowing CO2 to enter and be converted as organic acids through a ___ ___ resembling the C4 pathway.
- night
- PEP reaction
201
As the Calvin cycle requires ATP and NADPH, products of light-dependent reactions that does not occur at night, to function, the generated organic acids are ___ ___ ___ for later use
stored in vacuoles
202
The mesophyll cells' vacuoles release the organic acids that store CO2 during the ___ as the stomata ___ to preserve water.
- day
- close
203
The CO2 is released by an ___ ___ ___ ___ of chloroplasts, where it enters the Calvin cycle to enable photosynthesis
- enzyme in the stroma
204
almost identical to those in chloroplasts, having chlorophyll a but lacking chlorophyll b
Cyanobacterial light reactions
205
Accessory pigments of cyanobacteria
- phycobilins
- open-chain tetrapyrrole rings
206
the ___ ___ forms accumulation spaces for protons and the generation of a ___ ___
- folded membrane
- chemiosmosis gradient
207
Purple and green bacteria do not contain chlorophyll, either a or b, but have ____
bacteriochlorophylls
