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BIOL 190 > Exam 2 > Flashcards

Exam 2 Flashcards

1
Q

Define selective permeability

A

Allowing some substances to cross it more easily than others

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2
Q

What is the fluid mosaic model?

A

Used to demonstrate the membrane is a “mosaic” of various proteins dispersed within the bilayer, with only the hydrophilic regions exposed to water

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3
Q

True or False: Phospholipids within the plasma membrane can move within the bilayer

A

True

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4
Q

True or False: Proteins can not move within the bilayer

A

False

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5
Q

As temperatures cool, membranes switch from a fluid state to a …

A

Solid state

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6
Q

True or false: The fluidity of a plasma membrane is affected by the type of hydrocarbon tails in phospholipids

A

True

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7
Q

At lower temperatures, the Plasma Membrane is more fluid if…

A

Unsaturated hydrocarbon tails with kinks are present

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8
Q

The plasma membrane is less fluid if…

A

Saturated hydrocarbon tails are present

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9
Q

Define viscous

A

Less warm temperatures, cholesterol makes the membrane less fluid by restraining the movement of phospholipids

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10
Q

How does chloesterol effect membrane fluidity at warm temperatures?

A

cholesterol makes the membrane less fluid by restraining the movement of phospholipids

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11
Q

How does cholesterol effect membrane fluidity at low temperatures?

A

At low temperatures, it maintains fluidity by preventing tight packing

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12
Q

What are integral proteins?

A
  • Penetrate hydrophobic core
  • Often transmembrane proteins
  • Located all over the membrane
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13
Q

What are peripheral proteins?

A
  • not embedded in lipid bilayer

- appendages are loosely bound to the surface of the membrane

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14
Q

What are the six major functions of membrane proteins?

A
  • transport
  • enzymatic
  • attachment to cytoskeleton and extracellular matrix
  • cell-cell recognition
  • intercellular joining
  • signal transduction
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15
Q

What is cell-cell recognition?

A

The cell’s ability to distinguish one type of neighboring cell from another

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16
Q

What is the purpose of membrane carbohydrates?

A

To interact with surface molecules of other cells, facilitating cell-cell recognition

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17
Q

How are glycolipids formed?

A

Membrane carbs covalently bonded to lipids

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18
Q

How are glycoproteins formed?

A

Membrane carbs covalently bonded to proteins

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19
Q

Molecules that start on the inside face of the ER…

A

End up on the outside face of the plasma membrane

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20
Q

When is symmetrical distribution of proteins, lipids, and assorted carbs in the plasma membrane determined?

A

When the membrane is built by the ER and the Golgi apparatus

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21
Q

What causes selective permeability?

A

Membrane structure

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22
Q

What is selective permeability?

A

When a cell must exchange materials with its surroundings, a process controlled by the plasma membrane

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23
Q

Describe the permeability of hydrophobic molecules?

A
  • Nonpolar
  • Hydrocarbons, CO2, O2
  • Pass through membrane easily
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24
Q

Describe the permeability of hydrophilic molecules?

A
  • Polar
  • Sugars, H20, C6H12O6
  • Do not pass through the membrane easily
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25
Q

Describe the permeability of ions?

A
  • Na+, K+
  • A charged atom and its surrounding shell of water
  • Require transport proteins
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26
Q

What are the three mechanisms of transport?

A

Active
Passive
Bulk

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27
Q

What is passive transport?

A
  • Substances diffuse DOWN the gradient
  • Does not require ATP
  • Facilitated diffusion included
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28
Q

What is active transport?

A
  • Substances move against gradient
  • ATP required
  • Includes ion pumps and cotransports
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29
Q

What is bulk transport?

A

-Includes exocytosis and endocytosis

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30
Q

Define Osmosis

A

Mechanism of passive transport

Diffusion of water across a semipermeable membrane

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31
Q

How is the direction of osmosis determined?

A

By a difference in total solute concentration

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32
Q

True or false: Water diffuses from region of higher to lower solute concentration

A

FALSE

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33
Q

Define tonicity

A

Ability of a solution to cause a cell to gain/lose water

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34
Q

True or False: cells without rigid cell walls have osmotic problems in either a hypertonic or hypotonic environment

A

True

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35
Q

How do cells without rigid cell walls maintain internal environment?

A

Osmoregulation

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36
Q

Define osmoregulation

A

Control of water balance

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37
Q

What is special about the protist Paramecium?

A

It is hypertonic to its pond environment and has a contractile vacuole that acts as a pump

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38
Q

Define hypotonic

A
  • When solute concentration is less outside than inside the cell (cell gains water)
  • A cell swells until cell wall opposes uptake
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39
Q

What is the term for a hypotonic plant cell?

A

Turgid

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40
Q

Define hypertonic

A
  • When solute concentration is greater outside than inside the cell (cell loses water)
  • Membrane pulls away from cell wall (defined as plasmolysis)
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41
Q

What is the term for a hypertonic plant cell?

A

Plasmolyzed

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42
Q

Define isotonic

A

When solute concentration is the same inside as outside the cell (no net water movement)

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43
Q

What is the term for an isotonic plant cell?

A

Flaccid

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44
Q

What is the optimal environment for an animal cell?

A

Isotonic

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45
Q

What is the optimal environment for a plant cell?

A

Turgid (hypotonic)

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46
Q

True or False: Cell walls do not help maintain water balance

A

FALSE

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47
Q

Define transport proteins

A

Allow passage of hydrophilic substances across a membrane and are specific for the substance they move

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48
Q

What are channel proteins?

A

Have a hydrophilic channel that certain molecules or ions can use as a tunnel

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49
Q

Define aquaporins

A

Facilitate passage of water

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50
Q

Define carrier proteins

A

Bind to molecules to change shape to shuttle them across the membrane

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51
Q

Why is facilitated diffusion passive?

A

The solute moves down its concentration gradient

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52
Q

What are the inputs and outputs of the sodium potassium pump?

A

3 Na+ out
2 K+in
1 ATP used

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53
Q

What kind of transport mechanism is the Sodium Potassium pump?

A

Active

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54
Q

What is membrane potential?

A

Voltage difference across a membrane

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55
Q

True or false: the inside of the cell is negative compared to the outside

A

TRUE

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56
Q

Membrane potential favor the passive transport of ____ into the cell and _____ out of the cell

A

cations, anions

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57
Q

What is the electrochemical gradient?

A

2 combined forces driving the diffusion of ions across a membrane

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58
Q

What are the two forces of the electrochemical gradient?

A

Chemical and Electrical

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59
Q

What is the chemical component of the electrochemical gradient?

A

The ion’s concentration gradient

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60
Q

What is the electrical component of the electrochemical gradient?

A

Effect of the membrane potential on the ion’s movement

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61
Q

What is the electrogenic pump?

A

A transport protein that generates the voltage across a membrane

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62
Q

What are the typical examples of the electrogenic pump?

A 
Sodium potassium pump (In animals)
Proton pump (plants, fungi, bacteria)
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63
Q

Define cotransport

A

Occurs when active transport of a solute indirectly drives transport of another solute

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64
Q

What is the proton pump

A

Plants generally use gradient of H+ ions generated by proton pumps to drive active transport of nutrients into the cell

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65
Q

What is bulk transport?

A
  • Small molecules and water enter or leave the cell through the lipid bilayer or by transport proteins
  • Large molecules such as polysaccharides and proteins cross the membrane via vesicles
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66
Q

Define exocytosis

A
  • transport vesicles migrate to membrane, fuse with it, and release their contents
  • addition of plasma membranes
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67
Q

True or False: Many secretory cells use exocytosis to export their products

A

TRUE

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68
Q

Define endocytosis

A
  • The cell takes in molecules by forming vesicles from the plasma membrane
  • loss of plasma membrane
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69
Q

True or False: Endocytosis is a reversal of exocytosis involving different proteins

A

TRUE

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70
Q

What are the three types of endocytosis?

A

Phagocytosis
Pinocytosis
Recepter Mediated

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71
Q

What is Phagocytosis?

A

“Cellular eating”

Cell engulfs a particle in a vacuole

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72
Q

What is Pinocytosis?

A

“Cellular drinking”

cell creates vessicle around fluid

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73
Q

What is receptor mediated endocytosis?

A

Binding of ligands to receptors triggers vesicle formation

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74
Q

How does phagocytosis occur?

A

A cell engulfs a particle by wrapping pseudopodia around it, and packaging it within a vacuole. The particle is digested after the vacuole fuses with a lysosome containing hydrolytic enzymes

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75
Q

How does pinocytosis occur?

A
  • The cell gulps tiny droplets of extracellular fluid to tiny vesicles.
  • It is not the fluid itself that is needed by the cell, but the mlcs dissolved in the droplets.
  • Nonspecific in the protein substances it transports
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76
Q

Define Ligand

A

Any molecule that binds specifically to a receptor site of another molecule

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77
Q

How does receptor mediated endocytosis occur?

A

Enables the cell to acquire bulk quantities of specific substances, even though these substances may not be very concentrated in the extracellular fluid

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78
Q

Describe intracellular receptors

A
  • Flourid in the cytosol/nucleus of target cells

- small hydrophobic chemical messengers can easily cross membrane and activate receptors

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79
Q

What are examples of intracellular receptors?

A

Steroid and thyroid hormones of animals.

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80
Q

What is the role of an activated hormone receptor?

A

It can act as a transcription factor, turning on specific genes

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81
Q

Describe Protein Phosphorylation and Dephosphorylation

A
  • Signal is transmitted by a CASCADE of protein phosphorylations
  • This phosphorylation and dephosphorylation system act as a molecular switch
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82
Q

What is the role of the protein kinase?

A

Transfer phosphate groups from ATP to a protein

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83
Q

What is the role of the protein Phosphatase

A

To remove the phosphates

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84
Q

Describe the response of the phosphorylation and dephosphorylation

A
  • other pathways regulate the activity of enzymes
  • At each step, the number of activated products is much greater in the preceding step
  • ultimately a signal transduction pathway leads to regulation of one or more cellular activities
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85
Q

Define metabolism

A
  • The totality of an orgnaism’s chemical reactions

- an emergent property of life that arises from interactions between molecules within the cell

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86
Q

A metabolic pathway

A
  • Begins with a specific molecule and ends with a product

- Each step is catalyzed by a specific enzyme

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87
Q

What is an exergonic reaction?

A
  • releases energy that can perform work
  • spontaneous
  • negative delta G
  • catabolism
  • Goes down on a graph
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88
Q

What is an endergonic reaction?

A
  • Requires energy to perform work
  • nonspontaneous
  • positive delta G
  • anabolism
  • Goes up on a graph
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89
Q

What are the three types of work performed by the cell?

A

Chemical
Mechanical
Transport

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90
Q

How do cells perform work?

A

They manage energy resources by energy coupling

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91
Q

Define energy coupling

A

Use of an exergonic process to drive an endergonic one

92
Q

How are the bonds between phosphate groups of ATP’s tail broken?

A

Hydrolysis

93
Q

True or False: Energy is released from ATP when the terminal phosphate bond is broken

A

TRUE

94
Q

Why does this release of energy occur?

A

The chemical change to a state of lower free energy, NOT the phosphate bonds

95
Q

True or false: The energy from the exergonic reaction of ATP hydrolysis can not be used to drive an endergonic reaction

A

FALSE

96
Q

True or False: ATP drives chemical work

A

TRUE

97
Q

Chemical work consists of:

A
  • coupled reactions
  • overall delta g is negative
  • together the reactions are spontaneous
98
Q

During Transport work

A

ATP phosphorylates transport proteins

99
Q

During Mechanical work

A

ATP binds noncovalently to motor proteins and then is hydrolyzed

100
Q

How is ATP a renewable resource?

A

It is regenerated by addition of a phosphate group to ADP

101
Q

Where does the energy used to phosphorylate ADP come from?

A

Catabolic reactions in the cell

102
Q

Where is chemical potential energy stored?

A

ATP and drives most cellular work.

103
Q

Define catalyst

A

A chemical agent that speeds up a reaction without being consumed by the reaction

104
Q

What is an example of a catalytic protein?

A

An enzyme

105
Q

What is an example of an enzyme catalyzed reaction?

A

Hydrolysis of sucrose by the enzyme sucrase

106
Q

What is activation energy (Ea)-

A

-Initial energy needed to start a chemical reaction

107
Q

How is activation energy supplied?

A

The form of heat from surroundings

108
Q

How do enzymes lower the Ea barrier?

A

-Enzymes catalyze reactions

109
Q

What are the effects of enzymes on free energy and the rate of reactions?

A

Enzymes do not effect Ea and hasten reactions that would occur eventually

110
Q

How are enzyme-substrate complexes formed?

A

When enzymes bind to the substrate

111
Q

What is the active site?

A

Region on the enzyme where the substrate binds

112
Q

What is the induced fit of a substance

A

Brings chemical group of the active site into positioins that enhance their ability to catalyze the chemical reaction

113
Q

What can effect an enzyme’s activity?

A
  • Temperature
  • pH
  • Chemicals that specifically influence the enzyme
114
Q

True or false: Each enzyme does not require an optimal temperature and pH in which it can function

A

FALSE

115
Q

Define cofactors

A
  • Non protein enzyme helpers
  • Inorganic
  • Tightly bound
116
Q

What are some examples of cofactors?

A

Iron, zinc, copper

117
Q

What are coenzymes

A
  • Organic cofactors
  • Loosely bound
  • Released as normal part of the catalytic cycle
118
Q

What are the two types of enzyme inhibitors

A

Irreversible and reversible inhibitors

119
Q

What are irreversible inhibitors?

A

Inhibitor usually attaches to the enzyme by covalent bonds

120
Q

What are examples of irreversible inhibitors?

A

Some toxins and poisons, penicllins

121
Q

What are the two types of reversible inhibitors?

A

Competitive and noncompetitive

122
Q

What are competitive inhibitors?

A
  • They bind to the active site of an enzyme, competing with the substrate
  • can be overcome by increasing the concentration of the substrate
123
Q

What are noncompetitive inhibitors?

A

-They bind to another part of an enzyme causing it to change shape and making active sites less effective.

124
Q

True or False: Regulation of enzyme activity helps control metabolism

A

TRUE

125
Q

What would result if a cell’s metabolic pathways were not tightly regulated?

A

Chemical chaos

126
Q

What is allosteric regulation?

A
  • When a protein’s function at one site is affected by binding of a regulatory molecule at another site
  • May either inhibit or stimulate an enzyme’s activity
127
Q

What are most allosterically regulated enzymes made from?

A

Polypeptide subunits

128
Q

How does binding of an activator enzyme effect the form of the enzyme?

A

It stabalizes the active form of the enzyme

129
Q

How does the binding of an inhibitor enzyme effect the form of the enzyme?

A

It stabalizes the inactive form of the enzyme

130
Q

What are the activators and inhibitors of the catabolic enzymes when they regenerate ATP?

A

Activator: ADP
Inhibitor: ATP

131
Q

Define cooperativity

A

A form of allosteric regulation that can amplify enzyme activity

132
Q

How does cooperativity work?

A

Binding of one substrate molecule to active site of one subunit locks all subunits in active conformation

133
Q

Define feedback inhibition

A

The end product of a metabolic pathway shuts down the pathway

134
Q

How does feedback inhibition work?

A

It prevents a cell from wasting chemical resources by synthesizing more product than is needed

135
Q

What do catabolic pathways do?

A

Breakdown organic molecules

136
Q

Define cellular respiration

A

Breakdown of organic molecules for production of ATP

137
Q

What is aerobic respiration?

A

Respiration that consumes oxygen

138
Q

What is the chemical formula of cellular respiration?

A

C6H12O6 + 6O2 ——> 6CO2 + 6H20 + ATP

139
Q

What is anaerobic respiration?

A

Use inorganic molecules other than the oxygen as the final electron acceptor at the end of the electron transport chain

140
Q

Define fermentation

A

A partial degradation of sugars that occurs without oxygen

141
Q

What is an oxidation-reduction reaction?

A

Chemical reactions that transfer electrons by reactants

142
Q

How do you determine what reactant is oxidized/reduced

A

LEO goes GER

  • Loses electrons=oxidized
  • Gains electrons=reduced
143
Q

How do you determine what reactant is the oxidzing/reducing agent?

A

Electron donor=reducing agent

electron acceptor=oxidizing agent

144
Q

How do you label the reactants in a redox reaction when charges aren’t present?

A
  • Oxidized gain O, lose H

- Reduced gain H, lose O

145
Q

During cellular respiration, what is oxidized and what is reduced?

A

Glucose is oxidized

Oxygen is reduced

146
Q

What are the stages of cellular respiration?

A

Glycolysis
Pyruvate oxidation (acetyl coA formation)
Citric acid cycle
Oxidative phosphorylation

147
Q

Define glycolysis

A
  • Breaks down glucose into two molecules of pyruvate
  • Does not require oxygen
  • Occurs in cytoplasm
148
Q

What are the two phases of glycolysis

A

Energy investment

energy pay off

149
Q

What are the net inputs and net outputs of glycolysis?

A

Inputs: Glucose, 2 NAD+, 4 ADP +P
Outputs: 2 pyruvates, 2 ATP, 2 NADH, 2 H2O

150
Q

Define pyruvate oxidation (acetyl coA formation)

A

Completes breakdown of glucose

151
Q

What are the net outputs of pyruvate oxidation?

A

2CO2, 2 NADH, 2 Acetyl CoA

152
Q

Define citric acid cycle

A

Completes breakdown of glucose

Has 8 steps each catalyzed by a specific enzyme

153
Q

What are the net inputs and net outputs per glucose of the Citric acid cycle?

A

Inputs: 2 FAD, 6 NAD+, 2ADP
Outputs: 4CO2, 2 FADH2, 6 NADH, 2 ATP

154
Q

How do the inputs out and outputs differ if it were asked per pyruvate?

A

It is just half of each

155
Q

Following glycolysis and the citric acid cycle, what accounts for most of the energy extracted from food?

A

NADH and FADH2

156
Q

What electron carriers donate electrons to the ETC?

A

NADH and FADH2

157
Q

What does donation to the ETC do?

A

Powers ATP synthesis via oxidative phosphorylation

158
Q

What are most of the ETC’s components?

A

Proteins

159
Q

What is the final proton acceptor?

A

O2

160
Q

Define Oxidative Phosphorylation

A

Accounts for most of the ATP synthesis, powered by redox reactions

161
Q

Where is the ETC located?

A

The cristae of the mitochondrion (inner membrane)

162
Q

Where does kreb’s cycle occur?

A

Matrix

163
Q

Does the ETC gnereate ATP directly?

A

No. It releases energy in manageable amounts

164
Q

What is an example of chemiosmosis?

A

The use of energy in a H+ gradient to drive cellular work

165
Q

Describe the process of chemiosmosis

A
  • Electron transfer in ETC causes proteins to pump H+ from the mitochondrial matrix to the intermembrane space
  • H+ then moves back across the membrane, passing through channels in ATP synthase that uses the exergonic flow of H+ to drive phosphorylation of ATP
166
Q

What are the two components of oxidative phosphorylation?

A
  • ETC

- Chemiosmosis

167
Q

Describe the energy flow during cellular respiration

A

Glucose —-> Electron Carriers —-> ETC —-> Proton-motive force —-> ATP

168
Q

How many ATP are made during cellular respiration?

A

30-32 ATP

169
Q

How many ATP are made during glycolysis?

A

2 ATP

170
Q

How many ATP are made during citric acid cycle?

A

2 ATP

171
Q

How many ATP are made during Oxidative Phosphorylation?

A

26-28 ATP

172
Q

What kind of phosphorylation are glycolysis and citric acid cycle?

A

Substrate level phosphorylation

173
Q

Can glycolysis produce ATP with/without oxygen?

A

Yes

174
Q

In the absence of O2, how does glycolysis produce ATP?

A

Anaerobic respiration, uses an ETC with a different final proton acceptor

175
Q

Define fermentation

A

Glycolysis plus reactions that regenerate NAD+ which can be reused by glycolysis

176
Q

What are the two types of fermentation?

A

alcohol and lactic acid

177
Q

Describe alcohol fermentation

A
  • Pyruvate is converted to ethanol in two steps, the first releases CO2
  • ex// yeast used in brewing
178
Q

Describe Lactic acid fermentation

A
  • pyruvate reduced to NADH forming lactate as an end product

- ex// some fungi and bacteria, muscle cells

179
Q

How do muscle cells used lactic acid

A

To generate ATP when O2 is scarce

180
Q

To sustain high rates of glycolysis under anaerovic conditions, cells require

A

NAD+

181
Q

Describe facultative anaerobes

A
  • can survive using fermentation or cellular respiration

- ex// yeast, bacteria

182
Q

Describe obligate anaerobes

A

-carry out fermentation or anaerobic respiration and cannot survive in presence of O2

183
Q

What is the evolutionary significance of glycolysis

A

Glycolysis evolved in ancient prokaryotes before there was oxygen in the atmosphere

184
Q

Describe Catabolism

A
  • funnel electrons from many kinds of organic molecules into cellular respiration
  • proteins are digested to amino acids
  • fats digested to glycerol and fatty acids
185
Q

How do amino groups contribute to glycolysis or the citric acid cycle

A

they feed the two processes

186
Q

How is glycerol used?

A

Used in glycolysis

187
Q

How are fatty acids used?

A

Used to generate acetyl coA

188
Q

When fatty acids are broken down by beta oxidation what do they yield?

A

Acetyl CoA

189
Q

Describe biosynthesis (Anabolic pathways)

A

Body uses small molecules to build other substances

190
Q

What is the most common mechanism for control of cellular respiration?

A

Feedback Inhibition

191
Q

If ATP concentration begins to ____ respiration ____; When there is _____ respiration _____

A
  • drop, speeds up

- plenty of ATP, slows down

192
Q

What is the equation for photosynthesis?

A

6 CO2 + 6 H20 —> C6H12O6 + 6 O2

193
Q

Where do light reactions occur?

A

The thylakoids

194
Q

What does the process of light reactions do?

A
  • split water
  • release O2
  • Produce ATP (by phosphorylation)
  • Form NADPH
195
Q

Where does the Calvin cycle take place?

A

The stroma

196
Q

What does the calvin cycle do?

A

Form sugar from CO2 using ATP and NADPH

197
Q

What is Chlorophylla

A

-main photosynthetic pigment

198
Q

What does Chlorophyll b do?

A

Broadens spectrum used for photosynthesis

199
Q

What are carotenoids?

A

accessory pigments that absorb excessive light that would damage chlorophyll

200
Q

A photosystem consists of…

A

reaction center surrounded by light harvesting complexes

201
Q

What are light harvesting complexes?

A

pigment molecules bound to proteins

202
Q

What do light harvesting complexes do?

A

funnel the energy of photons to the reaction center

203
Q

What accepts an excited electron from chlorophyll a

A

primary electron acceptor in the reaction center

204
Q

What is the first step of the light reactions?

A

solar powered transfer of an electron from chloryphyll a molecule to primary electron acceptor

205
Q

What order are the photosystems in?

A

II first I second

206
Q

What wavelength does PS II absorb?

A

p680

207
Q

What wavelength does PS I absorb?

A

p700

208
Q

What do the two photosystems generate?

A

ATP and NADPH

209
Q

What are the two routes for electron flow during the light reaction?

A

Linear (noncyclic) or Cyclic

210
Q

What is Linear (noncyclic) pathway

A

primary pathway
involves both photosystems
produces ATP and NADH

211
Q

What is cyclic pathway

A

uses only PS I
Produces only ATP
Generates surplus ATP satisfying higher demand in calvin cycle

212
Q

How do chloroplasts and mitochondria generate atp and what sources of energy do they use?

A

Chemiosmosis

mitochondria: transfer chemical energy from food to ATP
chloroplasts: transform light energy into chemical energy of ATP

213
Q

True or false: Clavin cycle are reffered to as light independent reactions

A

TRUE

214
Q

What are light independent reactions

A

Don’t require light directly, and occur in daylight

215
Q

During Calvin cycle carbon enters the cycle as CO2 and leaves as a sugar named

A

Glyceraldehyde 3 Phosphate (G3P)

216
Q

How many times must Calvin cycle take place to generate one G3P? How many CO2 are produced?

A

Three times, 3 CO2

217
Q

What are the three phases of Calvin Cycle?

A

Carbon fixation
Reduction
Regeneration of the CO2 acceptor

218
Q

WHat is carbon fixation catalyzed by?

A

Rubisco

219
Q

What is the CO2 acceptor?

A

RuBP

220
Q

To generate one G3P mlc, you need

A

9 ATP

6 NADPH

221
Q

What are alternative mechanisms of carbon fixation?

A

dehydration

222
Q

On hot dry days plants close to ____ which conserves water but also limits photosynthesis

A

stromata

223
Q

During photorespiration

A
  • Rubisco adds O2 to the calvin cycle instead of CO2
  • Neither ATP or sugar are produced
  • may be an evolutionary relic because rubisco first evolved when atmosphere had more CO2 than O2
224
Q

Describe C4 Plants

A
  • Minimize cost of photorespiration by incorporating CO2 into 4 carbon compounds
  • These compounds are exported to bundle-sheath cells where they release CO2 that is then used in Calvin cycle
225
Q

Describe CAM plants

A
  • Open stromata at night to incorporate CO2 into organic acids
  • Stomata close during day and CO2 released from organic acids and used in calvin cycle.

BIOL 190 (4 decks)

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