2014-07-09 lecture 4 - lysosome, vacuole, mitochondrion, chloroplast (posted)
TRANSCRIPT
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
1/69
LYSOSOME
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
2/69
Functions of lysosomes
1
2
3
3. Controlled
Uptake ofnutrients
1. Digestive
2. Autophagic
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
3/69
1. Digestive Optimal pH for function is low (pH 4.6 - 5.0)
H+-ATPase activity (1001000 times cytoplasm acidity)
Glycosylated interior (inner leaflet) protectscompartment from pH damage
Enriched with ~40 types of hydrolytic (degradative)enzymes
2. Controlled uptake regulator Endocytic particles (or bacteria) form endosomes whichare routed to the lysosome for degradation.
Some bacteria target and happily live in endosomes eg. Coxiellaburnetti (Q fever)
3. Autophagic (micro/macro types) Organelle (macro) and ribosome (micro) turnover is
essential to remove damaged or malfunctioning cellcomponents (eg. mitochondria or chloroplasts)
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
4/69
Digestive
enzymes
Lysosome
Food vacuole
Plasma membrane
Digestion
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
5/69
Lysosome
Vesicle containing
damaged mitochondrion
Digestion
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
6/69
Mannose-6-phosphate (M6P)is added onto lysosomalproteins in the cis-Golgi (two step reaction)permits theiridentification later.
M6Pis recognized by the M6P receptor (MPR) in theTGNwhich sorts these proteins away from secretedprotein Patients with I- cell diseaseare deficient in the enzymes that
convert mannose to M6P, or lack proper M6P receptorsresultsin lysosomes filled with undegraded cell structures/molecules
At TGN, lysosomal proteins are packaged into clathrin-coated vesiclesfor transport to the lysosome
Mechanism for sorting lysosomal proteins
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
7/69
Lysosomal sorting using
clathrin coated vesicles
(CCV)
1 2
3 4
Cyto
TGN
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
8/69
Endocytosis involves the uptake of proteins andother macromolecules at the plasma membrane.
Bulk materials are taken up by the cell in two
ways: Within the membraneProteins are concentrated
during uptake (receptor mediated endocytosis).
Within the fluid phaseNo increase in theconcentration of the molecules
Pinocytosis (cell drinking)
Phagocytosis (cell eating)
Lysosomes in endocytosis
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
9/69
Pinosomes are generated by the process of pinocytosis(celldrinking). No pseudopod formationplasma membrane pinching using
receptors and COP like proteins in the coated pits
Pinch sites
Pinososome
Endocytosis: Pinocytosis
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
10/69
Rab proteins
Fusion to early endosomes
Phagolysosome (low pH)
Phagosomes are generated by the process of phagocytosis
(cell eating). Uptake of larger particles, dead cells and bacteria
Endocytosis: Phagocytosis
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
11/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
12/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
13/69
Many of the events in receptor mediated
endocytosis are similar to vesicle transport in the
secretory pathway.
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
14/69
Specific receptors are clustered together at sites
on the plasma membrane by binding to the coat
protein clathrin.
The cytoplasmic portion of receptors provide sites/
regions that recognize and determine which receptorsto internalize
1
Endocytosis step # 1: Formation of coated pits
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
15/69
Coat is formed from clathrin.
Three heavy chains and 3light chains are assembled
into a triskelion. Triskelions are assembledinto a basket-like structure onthe cytoplasmic face of thevesicle.
Adaptor proteinsconnectthe cytoplasmic side ofreceptors to clathrin.
2
3
1
Endocytosis step # 2: Coat assembly continues
until vesicle is formed and released into cytoplasm
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
16/69
Clathrin coated vesiclesused for both receptor-mediated endocytosisand for vesicle transport
from TGN to lysosome.
The adaptor proteins forTGN are different fromthose for plasma
membrane.
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
17/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
18/69
Example: Cholesterol uptake
Cholesterol is carried with apo-B
protein as LDL particle.
LDL receptor internalizes LDL.
Familial hyper-cholesterolemialeads to elevated blood
cholesterol:
Mutations to LDLRgene (encodes
the LDL receptor)
Mutations to apoBgene
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
19/69
Tftransferrin
TfRtransferrin receptor
Example: Iron uptake Iron is released from transferrin
in endosome
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
20/69
Peroxisomes
Peroxisomes can be formed eitherby de novosynthesis orgrowth/division.
Membrane bound: proteins within it
have homology to proteins of the ER Enriched with oxidative enzymes
Specialized organelles that function
in two ways: a and b-oxidation breaks down fattyacid chains
- Toxic oxygen species formation/breakdown
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
21/69
Peroxisomes
Urate oxidaseis not found in
humansuric acid can build
up leading to the illness called
gout.
Peroxisomes have 32unique proteins called PEX
that function as:
- Protein import machinery
- Enzymes
- Receptors
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
22/69
VACUOLE
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
23/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
24/69
Vacuoles are apredominant feature of
plant cells. Lysosomes are
predominately found inanimal cells and rarely inplant cells.
Vacuoles are membranebound compartments thathave similar functions aslysosomes. They contain:
Many acid hydrolases
V-type H+-ATPases
Vacuoles can occupy as much
as 90% of the volume of many
plant cells.
http://amit1b.wordpress.com/10-the-living-cell-gallery/
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
25/69
1. Defensive Toxic chemical repository
cyanide containing
glycosides
glucosinolates2. Vacuoles are storage
units
Stores solutes and
macromolecules such asions, sugars, amino acids,
proteins, and
polysaccharides, organic
acids
VacuoleGolgi
ER
chloroplast
mitochondria
Functions of vacuoles in plant cells
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
26/69
3. Intracellular
digestion
pH ~ 25
Organic acids assist
in maintaining low pH
The vacuolar
membrane isreferred to as the
tonoplast
Specific proteins:
Tonoplast intrinsic
proteins (TIP)
Vacuole
Turgor pressure
[Solute]
H2O
H2O
Plant cells have high
osmotic pressure
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
27/69
The Mitochondrion:Aerobic Respiration
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
28/69
Aerobic respiration
Aerobic respiration is a biological/metabolic process
where molecular oxygen (O2) is used to generateenergy in the form of ATP by breaking down a carbon
source
In most cases, lipids (fatty acids), carbohydrates, and
proteins are converted to pyruvate.
Pyruvate is broken down into CO2and water (H2O) by
the tri-carboxylic acid (Krebs) cycle (TCA).
The process generates electrons (e-) and NADHused
to drive the electron transport chain and create a proton
gradient used to synthesize ATP.
C6H12O6+ O2
6 CO2+ 6 H2O + energy
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
29/69
Aerobic respiration
Glucose
O2present
Pyruvate
Glycolysis
Fermentation
Lactate
NADH
NAD+
NAD+
NADH
O
Plasma membrane
NAD+
2ATP
O2absentPyruvate
Acetyl-CoA
TCA
Cycle
3NADH, 2FADH2
Electron transport chain
36ATP Cytoplasm
NAD+
NADHCO2
5 e- pairs
OH
OH
OH
OH
2CO2+ H2O
O
O
O-
(Ethanol)
CH2OH
HC
CH2OPO32-
OH
Glycerol 3-P
H3C COO-
Fatty acid
Fermentation is useful for aerobic respiration replenishes NAD+ supply
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
30/69
Mitochondria can self-replicate by fission.
Functions:
1. Synthesis of ATPvia the oxidation ofpyruvate: most ATP is produced byoxidative phosphorylation.
- The more energy a cell needs themore mitochondria (skeletal muscle)
- Mitochondria are localized near siteswhere ATP requirement is greatest
Example: near baso-lateral surface
of gut epithelium, where Na
+
/K
+
ATPase activity is highest
2. -oxidationof fatty acids (peroxisomesalso participate in this).
3. Apoptosis(programmed cell death).
Controlled
Cell death3
-oxidation
TCA
cycle
Acetyl-CoA
Acyl-CoA
2
1
ATP
Mitochondria
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
31/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
32/69
Mitochondrial outer membrane is distinct from the inner
membrane.
The outer membrane is permeable to small molecules.
Enriched with porinsthat form non-specific channels in
outer membrane (permeable to molecules < 10 kDa)
Outer membrane
Intermembrane space lumen
Cyto side
Intermembrane sideMatrix
H+
ADP + Pi ATP
MITOCHONDRIAL PORIN
Structure of mitochondria: Outer membrane
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
33/69
Mitochondria inner membrane:
Contains high abundance of cardiolipin
make membraneless permeable to protons.
Contains high abundance of protein (approx. 75% of mass):
electron transport chain (ETC) complexes and ATP
synthases.
Is highly convolutedjoins to double layered membrane
sheets called as cristae.
Is highly impermeable.
Both the outer and inner membranes have distinct protein importsystem.
Structure of mitochondria: Inner membrane
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
34/69
Metabolite enriched: TCA cycle intermediates
Soluble electron carriers eg. cytochrome c (cyt. c)
High proton concentration: slightly acidified space (pH ~56)
Intermembrane space
Matrix
H+
ADP + Pi ATP
Cyt.c
H+ H+H+H+ H+H+
H+H+
H+
H+
H+H+
ATP
H+
H+H+
ADP
Inner
Membrane
(IM)
Outer
Membrane
(OM)
Structure of mitochondria: Intermembrane space
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
35/69
Mitochondrial DNA (mtDNA),RNA, ribosomes:
Self-replicating and maternallyinherited.
Can be circular or linear
Protein: very high abundance
Pyruvate and fatty acidoxidations
TCA/Krebs cycle Mostly encoded by nuclear
genome.
Structure of mitochondria: Matrix
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
36/69
NADH
NADH FADH2
ATP ATP
ATP
CYTOPLASM
Glycolysis
Electrons
carried by NADH
Glucose PyruvatePyruvate
OxidationCitric Acid
Cycle
Oxidative
Phosphorylation
(electron transport
and chemiosmosis)
Mitochondrion
Substrate-level
phosphorylationSubstrate-level
phosphorylation
Oxidative
phosphorylation
ATP production
Major energy reserves in cells:
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
37/69
Major energy reserves in cells:
polysaccharides and fats
Starch granulesin potato tuber cells
Glycogen granulesin muscle
tissueGlycogen
Glucosemonomer
Starch
Cellulose
Hydrogen bonds
Cellulosemolecules
Cellulose microfibrilsin a plant cell wall
Fatty acids
Glycerol
Fat (triglyceride)
Making ATPs Step 1:
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
38/69
Glycolysis:break-down of glucoseto pyruvate
Each glucose produces: 2 NADH + 2
ATP
Lipolysis:
Triglyceridesfatty acids
Glycerol-3-phosphate shuttle:
triglyceridesglycerolglycerol-3-
phosphate
(In mitochondria: glycerol-3-phosphate
dihydroxyacetone-3-phosphate to
make FADH2)
Making ATPsStep 1:
Breaking down energy sources in the cytoplasm
Making ATPs Steps 2:
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
39/69
Making ATPsSteps 2:Acetyl-CoA production and TCA cycle
Fatty acids and pyruvate are
transported into mitochondria viapermeases.
Oxidation:
Pyruvateacetyl-CoA
Fatty acidsacetyl-CoA (-oxidation)
Fatty acids produce much more
acetyl-CoA than pyruvate
produces.
TCA cycle:
Each acetyl-CoA produces: 3
NADH + 1 FADH2+ 1 ATP
NADH and FADH2are used by the
elctron transport chain (ETC) for
oxidative phosphorylation.
Making ATPs Steps 3:
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
40/69
Electron transport chain(ETC):
Is composed of 4
complexes
Transfers electrons from
TCA cycle reactions to
terminal electron
acceptors.
O2
+ 2H+H2
O
Making ATPsSteps 3:
Oxidative phosphorylation
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
41/69
Electron transport chain
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
42/69
Electron donors: FADH
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
43/69
Complex II is also part of the TCA cycle: producing FADH2.
FADH2donates electrons to ubiquinone carriercomplex IIIcomplex IV (coupled with transporting H+).
Complex II does not transport H+.
Electron donors: FADH2
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
44/69
ATP synthase utilizes proton motive force
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
45/69
ATP synthase (F0-F1
ATPase) utilizes the H+
gradient to synthesize ATP.
H+move down theconcentration gradientand pulled by electrical
gradient across innermembrane through F0F1ATP synthase.
The F0domain (membrane
integral) form the H+
channel.
The F1domain (peripheral onthe matrix side of the innermembrane) synthesizes ATP
by rotational catalysis.
ATP synthase utilizes proton motive force
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
46/69
Rotational catalysis by ATP synthase
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
47/69
1 ATP molecule is produced for every 3 to 4 H+moving through ATP
synthase
3 ATP molecules for each 360odegree rotation of g subunit
Letters indicated refer to: O= open, L= loose, T= tight conformations of the F1subunit
Rotational catalysis by ATP synthase
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
48/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
49/69
Major functions of chloroplasts
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
50/69
Sites of photosynthesis in plants
conversion of photon (light)energy into chemical energy
(ATP and NADPH).
Sites of conversion of CO2to
sugars at expense of ATP andNADPH (CO2fixation also
known as the Calvin-Benson
cycle).
Site of synthesis and assembly of
some chloroplast components:
chloroplast genome, translational
machinery etc.
Major functions of chloroplasts
Structure of chloroplast: Membranes
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
51/69
1) Outer membrane:permeable to small molecules (810 kDasubstrates) diffused through porins.
2) Inner membrane:relatively impermeable, transportingmolecules for exchange to and from the cytoplasm
3) Thylakoid membrane:site of photosynthesis/photophosphorylation
- H+pumps and chloroplast ATP synthase (CF0
CF1
ATPasecomplex) is located in this membrane
Structure of chloroplast: Membranes
Structure of chloroplast: Stroma and lumen
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
52/69
Stroma:
ATP and NADPH production CO2fixation
starch synthesis and storage
chloroplast genome (generally circular DNA)
Thylakoid lumen: accumulation of H+
Structure of chloroplast: Stroma and lumen
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
53/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
54/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
55/69
A typical light harvesting complex
(LHC)
Two kinds of lightharvesting complexes(LHC):
LHCII: Higher lightenergy (lowerwavelength) absorption
LHCI: Lower light
energy (higherwavelength) absorption
Light dependent reactions: ATP and NADPH
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
56/69
Electrons are transported through photosystems and e-
carriers within the thylakoid membrane.
H+are transported from stroma into thylakoid lumen and
coupled to electron movement. NADP is final electron acceptor
H+gradient used by CF ATP synthase (CF0CF1ATPase)
to synthesize ATP.
Some electrons generated are used to synthesize
NADPH from NADP
Light-dependent reactions: ATP and NADPH
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
57/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
58/69
LHCII & PSII
Photosystem II
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
59/69
1- PSII operates maximally at 680 nm wavelength (chlorophyll a
P680)- Uses H2O as donorfor replacement electrons
- Water-splitting activity associated with PSII: 2H2O4H++ O2
- H+contribute to a proton gradient across thylakoid membrane
2- Electrons are passed from PSII to cytochrome b/f complex byplastoquinone(PQ)(insoluble electron carrier).
3- Electrons are passed through cytochrome b/f to plastocyanin
(soluble electron carrier). Movement through cytochrome b/f coupled
to H+pumping across thylakoid membrane, into the thylakoid lumen.
4- Plastocyanin (PC)is used as electron donor to replace electron
displaced in photosystem I(PSI).
Photosystem II
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
60/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
61/69
e- e-
e-
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
62/69
LHCI & PSI
Photosystem I
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
63/69
1- PSI operates maximally at 700 nm (chlorophyll a P700).
2- Electrons from plastocyanin (PC) are replaced.
3- Electron flow:
- Linear: The activated electron is transferred to NADP to formNADPH by ferridoxin NADP reductase.
- Cyclic: The activated electron cycles back through
cytochrome b/f complex to pump more H+across thylakoid
membrane.produces a H+gradient without NADPHproduction.
Photosystem I
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
64/69
Linear electron flowof photosystem I
e-
Fd
FNR
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
65/69
Cyclic electron flow of photosystem I
e-
e-
e-
CF ATP synthase: H+
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
66/69
CF ATP synthase: H+
gradientused by CF ATP
synthase to synthesize
ATP. ATP synthesis is similarly
organized as in
mitochondria.
Light-independent reactions: Calvin cycle
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
67/69
4. Glyceraldehyde 3-
phosphate (GAP) is
converted to
carbohydrates.
2. After splitting,
phosphoglycerate (PGA)
is phosphorylated by
expending ATP.
5. Conversion toribulose-1,5-
bisphosphate
(RuBP) to begin
the cycle again
3. NADPH is oxidizedto NADP+ and the
newly added Piis
removed from PGA to
form GAP.
1. CO2is fixed
by adding onto C2
of RuBP.
Light independent reactions: Calvin cycle
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
68/69
-
8/12/2019 2014-07-09 Lecture 4 - Lysosome, Vacuole, Mitochondrion, Chloroplast (Posted)
69/69