Midterm 1-Plant physiology Flashcards

1
Q

What are some of the major environmental roles of plants?

A

Produce O2, Store Co2, Move water from land to the atmosphere, Primary producers of the food chain

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2
Q

Major Requirements for plants

A

1)Light
2)Co2
3)H2O
4)Nitrogen
5)Potassium
6)Phosphorus
7)Magnesium

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3
Q

Shoot system

A

Composed of the stem,leaves,and fruits these appendages are used to absorb sunlight, perform gas exchange, and where reproduction occurs

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4
Q

Root system

A

Below ground portion of the plant responsible for anchoring the plant,absorbing water and nutrients, storing energy, and maintaining symbiotic bacteria colonies

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5
Q

Tap root

A

A singular long thick root that grows down from the plant which the remained of the root system will branch off of. Found in eudicot plants.

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6
Q

Fibrous roots

A

a root that is one of many similar slender roots branching directly from the base of the stem of a plant. Found in Monocots

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7
Q

Phenotypic plasticity in plants

A

1) Leave sizes will change according to avalible sunlight with shaded plants producing larger leaves
2) Root size and adjust for drought conditions either shrinking or growing rapidly
3)Height as elevation changes, will decrease to be less wind prone

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8
Q

What is this a modification of, Name it and describe it’s function

A

Root, Anchor Root, Grow out of the stems and allow the plant to anchor itself to walls or tall plants

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9
Q

What is this a modification of, Name it and describe it’s function

A

Root, Prop Root, Help stabilize tall plants like corn from winds

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10
Q

What is this a modification of, Name it and describe it’s function

A

Root, Pneumatophores, specialized root structures that grow out from the water surface and facilitate the aeration necessary for root respiration in hydrophytic trees

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11
Q

What is this a modification of, Name it and describe it’s function

A

Root, Storage roots, Store carbohydrates and nutrients as a part of the taproot

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12
Q

What is this a modification of, Name it and describe it’s function

A

Shoot, Water Storage system, Stores water

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13
Q

What is this a modification of, Name it and describe it’s function

A

Shoot, Stolons, used in asexual reproduction

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14
Q

What is this a modification of, Name it and describe it’s function

A

Shoot, Rhizomes,Produce new plants copies and store carbs

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15
Q

What is this a modification of, Name it and describe it’s function

A

Shoot, Tubers, Stores carbohydrates under the ground

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16
Q

What is this a modification of, Name it and describe it’s function

A

Shoot, Thorns, protect from herbivores eating the plant

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17
Q

Two main parts of a leaf

A

Petiole and Blade

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18
Q

Name, Function

A

Simple leaf, Able to photosynthesize a lot

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19
Q

Name,Function

A

Compound leaf, reduce rain and wind damage

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20
Q

Name function

A

Double compound leaf, Reduce rain and wind damage

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21
Q

Name, Function

A

Needles, Found in Very hot or Very cold climates as they minimize water loss, poor at synthesis but last year round

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22
Q

What is this a modification of, Name it and describe it’s function

A

Leaf, Bulb,Stores food for the plant

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23
Q

What is this a modification of, Name it and describe it’s function

A

Leaf, Succulent leaves, stores water

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24
Q

What is this a modification of, Name it and describe it’s function

A

leaf,Tendrils,allows plant to stabilize itself and climb onto supports

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25
What is this a modification of, Name it and describe it's function
Leaf,Floral mimic, attracts pollinators to it's actual flower
26
What is this a modification of, Name it and describe it's function
Leaf, Traps, Allows plants to digest prey
27
Middle lamela
A pectin glue which holds plant cells together
28
Primary wall
Cellulose based plant wall that all plant cells have which keep the plant upright and prevent the cell from lysing from vacuole
29
Secondary wall
A wall found in specialized cells made of lignin and cellulose that provides strength to the plant
30
Simple pits
Thin areas of secondary walls that connect between cells
31
What is this? How can you tell?
Primary cell wall, Pectin in the structure and no lignin
32
What is this? How can you tell?
Secondary cell wall, you can see primary cell wall above it, presence of lignin
33
Why is cellulose indigestible to humans, why can some animals digest it?
The presence of B-bonds instead of the typical A-bonds and forms long thin sheets, Some animals use symbiotic bacteria to break it down
34
differences in the organelles of a plant vs animal cell
1) Large central vacuole(s) 2)Chloroplast 3)Reduced mitochondria
35
Plasmodesmata
Small gaps in the primary wall that allow connection to nearby plant cells
36
Structural differences of plant vs animal cells
1)Plant cells are cubical 2)Plant cells are larger than animal cells 3)Animal cells lack Plasmodesmata
37
What is this, Name it and describe it's function
Plastid, Chloroplast, photosynthesis
38
What is this, Name it and describe it's function
Plastid, Amylosplast, stores sugar
39
What is this, Name it and describe it's function
Plastid, Chromoplast provides pigmentation to plants
40
Leaf modifications
Bulbs, succulent leaves,Tendrils, Floral mimic, Traps
41
Root modifications
anchor root, prop root, pneumatophores, storage roots
42
Shoot modifications
Water storage, stolons, rhizomes, tubers, thorns
43
Three types of plant tissues
1)Dermal 2)Ground 3)Vascular
44
Dermal tissue function
An outer coating of plants that helps prevent water loss,protect against pathogens, and in the roots absorb water and neutrients
45
Stomata
An opening in the dermal tissue composed of two guard cells that facilitate gas exchange
46
Cuticle
A waxy outer coating of plants that helps prevent the loss of water to the atmosphere
47
How does the positioning of the stomata relate to the plant type?
Stomata is placed wherever there is contact with the air so Aquatic plants=no stomata Floating plants=upper surface only Land plants=Stomata concentrated at the top of the plant but underside also has them.
48
Trichomes
Small hair like appendages found on the dermal tissue of plants that reflect sunlight,reduce water flow, can act as barbs and can act as traps
49
What cell type is this? How can you tell?
Parenchyma, you can tell because of the thin cell walls and the intercellular space
50
Three types of ground tissue
Parenchyma, Sclerenchyma,Collenchyma
51
What cell type is this? How can you tell?
Collenchyma, thickened primary cell wall
52
What cell type is this? How can you tell?
Sclerenchyma, thickened secondary cell wall
53
Parenchyma
Most abundant type of ground tissue, responsible for photosynthesis as well as starch storage. It is totipotent and is able to heal wounds or perform asexual reproduction
54
totipotent
A cell that retains it's ability to divide and differentiate
55
Collenchyma
unevenly thickened primary cell wall and sit near the vascular bundles of the stem providing flexible support
56
Sclerenchyma
Thick secondary cell walls, these cells are dead at maturity and provide rigid support for the plant. Composed of Sclerids and fibers
57
Xylem
Water containing cells that are hallow and lack cell wall ends transporting water and sugars up from the roots to the shoots. Composed of trachids and vessel elements
58
Trachids
one of the major components of xylem containing many pits through which water will flow through
59
Vessel elements
Found in angiosperms, they are a type of cell found in xylem that are longer and wider than trachids, they have both pits and perforations
60
Phloem
a type of vascular tissue that transports sugar, amino acids,hormones up and down the plant. Composed of seive-tube elements and companion cells
61
companion cells
maintain the cytoplasm & plasma membrane of sieve-tube elements via the plasmodesmata
62
Seive-tube elements
- long, thin cells with perforated ends (sieve plates). Lack nuclei & require companion cells to survive
63
What is this, what plant type, how can you tell?
Monocot stem, vascular bundles embeded at random in the stem with phloem facing outward and xylem facing inward
64
What is this, what plant type, how can you tell?
Dicot stem, Vascular bundles aranged in a circular pattern with phloem,cambium,xylem and piths at the core of the stem
65
What is this, what plant type, how can you tell?
Monocot root,xylem is aranged in a star shape and a central pith is present
66
What is this, what plant type, how can you tell?
Dicot root, xylem is aranged in a cross shape, and there is no central pith
67
Monocot
1 cotlydon, narrow leaves with parallel veiniation, scatered vascular bundles and flowers with multiples of 3
68
Eudicot
2 cotlydon, broad leaves with network veination, circular bundles of vascular tissue, and flowers in multiples of 4 or 5
69
Primary growth
Growth of a plant which lengthens the tips of the plants and the roots of the plant. The primary xylem and phloem are formed in this growth
70
Secondary growth
Growth of the plant which widens the roots and shoots of the plant. This is done through growth of the secondary xylem and phloem
71
Apical bud
the type of bud located at the top (apex) of the plant, particularly at the very tip of the main stem that will only grow when damaged otherwise prevents continuous primary growth
72
Meristem
totipontent cells which form the apical meristem
73
How can you identify the meristem cells in this picture?
1)Small size 2)Cuboidal shape 3)Large nuclei 4)Nuclei is central 5)Thin cell walls 6)small vacuole 7)Desne cytoplasm
74
3 types of meristem tissue
1)Protoderm 2)Ground meritstem 3)Procambium
75
Protoderm
Meristem which differentiates into dermal tissue
76
Ground meristem
Meristem which will differentiate into parenchyma, collenchyma,and sclerenchyma
77
Procambium
Meristem which diffrentiates into xylem and phloem
78
3 zones of primary growth
1)Celleular division (protoderm, ground meristem, procambium) 2)Cellular elongation (Vascular,ground,dermal) 3)Cellular maturation( Forming of structures)
79
Root cap
protects meristem using a lubricante that helps guide the growth of the root downward
80
Cambium
Forms the cylinders of cells dividing phloem and zylem that will differentiate into the secondary phloem and zylem
81
Types of cambium
1)Cork cambium located near the edge of the shoot 2)Vascular cambium, separates phloem and xylem
82
Lenticles
openings in bark that allow gas exchange. Inconspicuous in many tree species.
83
Heartwood
Dark xylem interior wood used as a structural support, incapable of water transport. It does produce resin and gum
84
Sapwood
Outer layer, light coloured xylem that conducts water
85
What can tree rings tell us about a tree?
Dry, cold, low sunlight-very little growth in the rings Warm,rainy, sunlight abundant- large growths in the tree rings
86
Isotonic
Solute concentration inside and out of the cell is equivalent meaning no net movement of water
87
Hypertonic
Solute concentration is greater outside of the cell than inside and water moves from the cell to the enviroment
88
Hypotonic
Solute concentration is greater inside the cell than outside of the cell leading to water flowing from the environment into the cell
89
Water potential
Potential energy of the water compared to that of pure water at atmospheric pressure & room temperature
90
How is water potential calculated
Ψ=Ψsolute+Ψpressure where solute is always negative and pressure is positive in living cells but negative in xylem
91
Solute potential
tendency for water to want to move via osmosis
92
Pressure potential
Comprised of turgor pressure and wall pressure it is the tendency for water to move in response to changes in pressure
93
Three hypothesis for water transport
1)Root pressure 2)Capillary action 3)Cohesion tension theory
94
Symplastic route
water moves across root cells through the plasmodesmata, only applies to small solutes
95
Transmembrane route
Water moves between the membranes of cells via aquaporins
96
Apoplastic route
water moves along the cell walls until it hits the casparian strip and is then forced into the transmembrane or symplastic route
97
Casparian strip
Ring of waxy suberin preventing things coming from the cell walls into the plant
98
Root pressure
water and ions move into the root increasing Ψs in the roots forcing water up the plant
99
Guttation
the process of secretion of water droplets from the pores of some vascular plants like grass and is due to root pressure
100
Capillary action
movement of water up a narrow tube due to three forces surface tension, adhesion and cohesion
101
Conditions for transpiration
1)Stomata are open 2)Atmosphere must be drier than air in the leaves
102
What force is used to open stomata
turgor pressure
103
Two factors that cause the stomata to open
1)Blue light response 2)Photosynthesis
104
How do stomata open
1)Phototropins are activated via blue light 2)Proton pumps create a gradient by moving H+ outside the cell membrane 3) To balance this K+ is brought in and Cl- helps move H+ back into the cell 4)K+ causes the conversion of starch into malate, increasing solute concentration and forcing water inside the cell
105
Factors that reduce soil water potential
Salty soil Dry air Irrigation and salinification
106
xerophytes
Plants in dry habitats have adaptations that help them slow transpiration and limit water loss
107
Photo synthesis-transpiration compromise
To reduce the loss of water in dry environments stomata close but with out open stomata no Co2 can be used for photosynthesis
108
How do plants survive highly salty environments
Storing high concentration of solutes in their roots to allow water to still move towards their roots
109
How do plants survive dry environments
Cuticle,Trichomes,crypt stomata, needle leaves,succulent ass behaviour of opening stomata at night
110
Translocation
Movement of sugars from sources to sinks where the sinks are on the smae side of the plant as the source
111
Pressure flow hypothesis
1)Source cells move sugars into companion cells via active transport 2)Water moves from xylem into phloem via osmosis increasing pressure 3)Pressure increase causes water to flow down the phloem into the sink
112
Two types of cotransporters
Symporters- transported good and its companion end up on the same side Antiporter- transported good and companion end up on opposite side
113
How does pholem unload sugar at the sink
1)Sucrose moves into companion cell via concentration gradient 2)Sucrose is moved into a tonoplast via an antiporter or is used by the developing cell
114
Macro Nutrients
N,P,K,Mg,Ca,S
115
Micro nutrients
Fe,Mn,Zn,Cu
116
Mobile Nutrients
Nutrients that move around the leaves from old to new, Nitrogen,Potassium,Phosphorus,Magnesium, Zinc, Molybdenum
117
Immobile Nutrients
Nutrients that cannot be moved around the plant, Calcium,Iron,Sulphur,Copper,Manganese,Boron
118
How does soil texture impact plant growth
1)Ability of plant to penetrate the soil with roots 2)Soil retention of water 3)Air spaces necessary for respiration
119
Loams
A soil type that combines sand,silt, and clay as well as organic matter, it is the idea growing condition for plants
120
Leaching
The loss of nutrients to the soil due to excess water moving through the soil
121
Major soil anions
Phosphate,Sulphate,Nitrate, and Chlorine
122
Why are cations hard to acquire from the soil?
Organic matter is negatively charged and so attracts the positive cations making them difficult to obtain
123
Major soil cations
Ca2+ , Mg2+ , K+ , Na+
124
Soil Ph and plant growth
Slightly acidic conditions ph 5.5-7 are preferred by plants as it makes cation exchange easier to preform
125
Cation exchange
Root hairs will release CO2 into water which reacts to form H+ ions that free the cations attached to organic matter making them available for uptake
126
CEC
Cation Exchange capacity, Measures negatively charged sites in soil available to bind cations & release plant nutrients, organic matter like clay has higher CEC than inorganic sand or gravel
127
Describe the uptake of both cations and anions in plants
1)H+ is pumped outside of the membrane creating a gradient 2)Cations follow the gradient and move in via a proton channel 3)H+ and Anions move inward via co transporter
128
Describe the mutalistic relationship between Mycorrhizal Fungi and Plants
1)Increase surface area of plant roots allowing for more nutrient absorption 2)Help to acquire macro nutrients 3)Protect plants from invaders with antibiotics 4)Produce auxin to stimulate plant root growth
129
Passive exclusion
Exclusion of toxic ions via lacking the proper transporters to move them within the cell
130
Active exclusion
Exclusion of a toxic ion via storing said ion in a tonoplast to prevent it from damaging the plant or through the use of metallothioneins and phytochelatins
131
metallothioneins and phytochelatins
Enzymes that detoxify harmful ions to the plant
132
Atmosphere composition
78% nitrogen, 21% oxygen,0.04% CO2 and 0.96% everything else
133
Why is atmospheric nitrogen largely inaccessible
Nitrogen forms a triple bond with itself into a N2 molecule that is extremely stable and difficult to break apart
134
Nitrogen Fixation
The process of turning atmospheric nitrogen into usable forms of nitrogen (NH3,NO2,NO3) via bacteria or archea
135
Describe the steps of Nitrogenous catalyzed conversion of N2 into NH3
1)Small nitrogenase complex with the help of 16 atp causes iron3 to be reduced producing electrons 2)Mo-F-S capture the atmospheric nitrogen in the large complex 3)The excess electrons from the reduction of iron 3 are passed to the Mo-Iron 2 complex 4)Mo-Fe2 complex reduces N2 into NH3
136
nodules
special area of the the plants root where symbiotic nitrogen fixing bacteria are stored
137
rhizobia
Nitrogen fixing bacteria that have a symbiotic relationship with legumes
138
leghemoglobin
protects nitrogenase by binding O2, which interferes with its activity
139
Process of infecting roots with rhizobia
1)Root hairs release flavanoids which attract the rhizobia 2)Rhizobia produce nod factors as they approch the root which begins the formation of the infection thread 3)Rhizobia multiply and enter the plant through the infection thread 4)Infection thread then forms a membrane around the rhizobia 5)Nod factors stimulate cell division in the root hairs and form the nodules
140
Parasitic plants
Plants that obtain water and nutrients by penetrating another plants xylem using Haustoria
141
Haustoria
penetrates the tissues of a host and absorbs nutrients and water
142
Epiphytes
grow on leaves or branches of trees Not parasitic, but use host for support and access to sunlight, due to not having proper roots they absorb water through their leaves through the air or from rainwater
143
Carnivorous plants
use modified leaves to trap insects & other animals usually found in bogs as they have little access to nitrogen from the soil
144
Light coupled Reaction
1)H2O split to form O2 2) Electrons from H2O are excited by light energy 3) High-energy electrons are transferred to the electron carrier NADP+, forming NADPH 4)ATP is produced
145
Light-independent reactions (Calvin cycle)
1)Produce sugar (organic C) from CO2 byusing up the Electrons and ATP from light-dependent reactions are used to reduce CO2
146
Stroma
analogous to the mitochondrial matrix and contains many metabolic enzyme
147
Stroma Lamelle
connect thylakoids of two different grana. They increase the efficiency of photosynthesis by keeping grana at a distance so that they do not clutter together
148
Thylakoid
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.
149
Pigments
absorb specific wavelengths of light and reflect others
150
Chlorophyll A
the predominant type of chlorophyll found in green plants and algae
151
Light harvesting complex
Captures light energy and passes the energy from pigment molecule to pigment molecule until it ejects two electrons to Chlorophyll A
152
What happens when light hits a surface?
1)Reflected 2)Absorbed 3)Transmitted
153
Cartenoids
Absorb blue & green light * Reflect & transmit yellow, orange, & red light
154
Chlorophylls A and B
Absorb red & blue light * Reflect & transmit green light * Main photosynthetic pigments
155
Why does Chlorophyll look like this
1)Head absorbs light 2)Tail anchors Chlorophyll to thalkaloid
156
Carotenoids & xanthophylls function in plants
1. Extend the range of wavelengths of light energy capture 2. Protect chlorophyll from damage by absorbing some of the light energy & stabilizing free radicals 3. Provide colour to flowers & fruits
157
Why do leaves change colour in fall?
Chlorophyll production stops so Chlorophyll is broken down & components(N) stored in stem & roots for use in spring this Prevents loss of N from plant if the green leaves were to drop to the ground
158
General formula for photosynthesis
CO2 +H2O+light energy-> (CH2O) +O
159
Photosystem
group of 300–400 chlorophyll & accessory pigments in the thylakoid membrane
160
3 Possibilities for energized electrons
1)Florescence or release of heat energy 2)Resonance Energy Transfer 3)Reduction/Oxidation where electrons are transferred to a new host
161
Antenna Complex
Molecules which absorb light energy passing the energy to neighbouring antenna via resonance energy transfer
162
Photosystem 1
Generates NADPH from reduction of NADP+ using H+ from Photosystem II
163
Photosystem 2
Generates ATP from a proton gradient established using photon energy and Splits H2O to obtain an electron that is passed to Photosystem I
164
Describe the production of ATP in Photosystem 2 complex
1) pheophytin accepts electrons 2)Electrons enters electron transport chain across thylakoid membrane 3)Electrons are then passed to plastoquinone which carry them to the cytochrome complex 4)PQ transports H+ from chloroplast stroma to thylakoid lumen, increasing [H+] 1,000x 5)Creates an electrochemical gradient and proton motive force 6)Protons move down their concentration gradient through ATP synthase, creating ATP
165
Formula for water splitting
2H2O -->4H+ 4e- +O2
166
Describe the process of generating NADPH using photosystem 1
1. Electron from Photosystem II passed to Photosystem I by plastocyanin (PC): links the 2 photosystems together 2. Special pair of chlorophyll molecules (P700) absorb 700 nm wavelength: electron is excited again by photons & are transferred to ferredoxin 3. Ferredoxin transfers electron: NADP+ is reduced to NADPH via NADP+ reductase
167
Z scheme
electrons are excited by photosystem II to generate ATP then excited again by photosystem I to reduce NADP+ to NADPH
168
Cyclic electron flow
Photosystem I also sends excited electrons back to the electron transport chain to generate ATP instead of passing them to NADP+ to form NADPH
169
Calvin Cycle
series of chemical reactions that convert CO2 into sugar
170
Fixation
CO2 reacts with RuBP and RuBisCo The resulting 6-C molecule splits into 2, 3-C molecules of 3PGA
171
Reduction
3PGA are phosphorylated by ATP & reduced by NADPH producing glyceraldehyde 3-phosphate (G3P) One G3P is used to make sugar
172
Regeneration
The remaining 5 x G3P used to regenerate RuBP
173
Roles for G3P
1. G3P used to make amino acids, nucleotides, & other molecules 2. G3P broken down via cellular respiration in the mitochondria to generate ATP 3. Excess G3P is converted into starch for storage 4. G3Ps are used to make sucrose, a disaccharide
174
Rubisco
Cubical molecule that Catalyzes the addition of either CO2 or O2 to RuBP
175
Cost of each step in the Calvin cycle plus its net product
1. Fixation step * 3 RuBP, 3 CO2 , 3 H2O 2. Reduction Step * 6 ATP , 6 NADPH 3. Regeneration Step * 3 ATP Product: 1G3P
176
Regulatory mechanisms for photosynthesis
1)When sugar content is too high storage of sugars becomes preferred over synthesis of new sugars 2)When Light or CO2 levels are low RUBISCO becomes deactivated 3)If O2 content is too high then photorespiration occurs instead of photosynthesis
177
Photorespiration
a process which involves loss of fixed carbon as CO2 in plants in the presence of light, wastes energy and steals carbon which supresses the photosynthesis process
178
C3 vs C4 pathway
the length of the carbon chain of the compound CO2 is organically fixed into where C3 uses the Calvin cycle and C4 can use both the Calvin cycle and the Hatch-Slack Pathway
179
C4 Pathway
1. HCO3- (1-C) reacts with phosphoenolpyruvate (3-C) to form a 4-C molecule (malate or aspartate) * Enzyme PEPCase 2. 4-C molecule diffuses close to vascular bundles 3. Enzyme NADP-malate dehydrogenase releases CO2 yielding 3-C pyruvate. CO2 is taken up by chloroplasts, increasing the concentration of CO2 for rubisco 4. 3-C pyruvate diffuses back to external region 5. Enzyme pyruvate-phosphate-dikinase regenerates phosphoenolpyruvate
180
Kranz anatomy
Inner ring of bundle sheath around vascular tissue, outer ring of mesophyll cells * Makes a diffusion barrier between mesophyll cells that uptake CO2 from rubisco in bundle sheath cells, facilitating C4
181
Benefit of Kranz anatomy
Increases CO2 concentration in bundle-sheath cells where RuBisCo is active so less O2 binds Spatial separation of CO2 absorption & C fixation in the Calvin cycle
182
C4 photosynthesis benefit
High affinity for CO2 by PEP carboxylase (no competition with O2) means stomata can be open for shorter periods of time, reducing water loss
183
Examples of C4 plants and their growing conditions
Corn,millet,Cabbage all prefering warm and dry climates
184
CAM Plants
keep stomata closed during the heat of the day and open them at night when it is cooler
185
Night time reaction of CAM plants
Stomata open; CO2 enters, reacts with H2O to form HCO3- PEPCase catalyzes reaction between HCO3- & 3-C phosphoenolpyruvate forming 4-C oxaloacetate Oxaloacetate is reduced to malate by NAD(P)+- malate dehydrogenase and is stored in a vacuole
186
Daytime reaction of CAM plants
Stomata closed * Malate released from vacuoles & is transformed by NADP-malic enzyme into 3-C pyruvate & CO2 * CO2 enters chloroplast where it increases the CO2 concentration around RuBisCo for the Calvin cycle
187
What type of photosynthesis leaf is this, how can you tell?
C3, not super efficient leaf design
188
What type of photosynthesis leaf is this, how can you tell?
C4, Bundle Sheaths and Leaf anatomy is designed to intercept CO2 as soon as it enters the plant
189
What type of photosynthesis leaf is this, how can you tell?
CAM, Presence of Aquiferous Parenchyma
190
Which plant type has the advantage in warm environments
C4 plants have a competitive advantage over C3 plants due to a lower rate of photorespiration
191
Which plant type has the advantage is cooler climates
C3 plants have a competitive advantage as most of their photosynthetic cells complete the Calvin cycle
192
Which plant type has the advantage in dry climates
CAM plants have a competitive advantage as they conserve water that would be lost to transpiration during the heat of the day
193
Rank the plant types by photo respiration rate
C3>C4>CAM
194
Order Of Enzymes Electrons pass through between photosystem 1 and 2
pheophytin->electron transport chain->plastoquinone carries to cytochrome complex->plastocyanin->ferredoxin->NADP+