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117 Cards in this Set
- Front
- Back
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Endomembrane system
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All the membranes within the cell inside the plasma membrane... Golgi apparatus, lysosomes, ER, vesicles, endosomes, peroxisomes
-primary center for protein and lipid synthesis in eukaryotes |
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Protein Sorting Pathways
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-Gated Transport
-Transmembrane Transport -Vesicular Transport |
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Polysomes
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Cytosolic protein- free in the cytoplasm
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Gated transport
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Cytosol to nucleus (through nuclear pore)
-fully folded |
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Transmembrane transport
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Needs to pass through membrane/lipid bilayer- needs to be mediated
-Occurs in mitochondria, ER, choloroplasts peroxisomes -Protein needs to be unfolded- energy required |
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Vesicular Transport
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After accomplishing transmembrane transport, from ER to Golgi
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Pulse-Chase experiment
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Pulse cell w/ radio-labelled leucine- able to see protein synthesis occuring in the ER
Chase w/ unlabelled amino acids- after protein synthesis- where do they go? -Immediatley- in rough ER -after 20 min- in golgi -after 120 min - in secretory vesicles |
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Rough ER
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-Synthesis of membrane-bound, soluble (ER, Golgi, or lysosomal), and secretory proteins
-Rough bc of ribosomes Lumen=newly manufactured proteins undergo folding and other types of processing |
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Smooth ER
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-Sequestration of Ca 2+ (cell signaling)
-Synthesis of steroid horomones -Enzymes for detoxification -Enzymes for glucose release No ribosomes- no protein synthesis. i.e. liver cells |
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ER Proteins
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Any protein making its way to the ER needs to be targetted to the ER- needs signal attached to cytosolic protein
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Co-translation translocation
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Secretory proteins into ER lumen
-Mechanism: -signal sequence in amino acid -SRP (signal recognition particle) binds to signal sequence on newly translated protein in the cytosol -Ribosome recruited -SRP binds to receptor in ER membrane -Protein pushed through translocon into ER-> SRP released through GTP hydrolysis -Protein refolded in the ER Proved w/ experiment using microsomes( cell free protein synthesis |
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Glycosylation
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Adding one or more carbohydrate groups to proteins- results in glycoprotein
-Starts in ER and goes to golgi N-linked-> ER happens at nitrogen (covalent bond) (Asparagine) -most common O-linked-> Golgi- happens at oxygen (has OH group on sugar) -subsequently- modification of N-linked sugars in golgi Oligosaccharid protein transferase- present in ER membrane (peripheral or transmembrane) ALWAYS facing the lumen *Only add sugars to proteins as oligosacchardies on the lumen side of the membrane -Eventually the vesicle fuses w/ the membrane and the carbohydrates face the exterior of the cell |
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Post-translational processing
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Folding and glycosylation
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Membrane Asymmetry
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N-terminus- out of the cell
C-terminus-cytosol -Starts at ER and is maintained |
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Golgi apparatus
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Stacks of membrane bound vesicles called cisternae
CisFACE- side of Golgi facing cytosol towards ER- recieves products from the rough ER transFACE- side of Golgi facing plasma membrane away from ER- ships products toward cell surface -trans and cis cisterna are hard to tell apart except when using protein stains -specific proteins are found in each type of cisterna -Sequencial processing of sugars through the Golgi |
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Transport through golgi
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-Vesicular transport model- smaller protein transport (bud from cisterna)
-Cisternal maturation model -cisterna mature from cis-medial- trans -allows cisterna to be renewed -allows larger proteins that would not fit in the vesicle (i.e. collagen) to be transported |
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Vesicular Traffic
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-Lipid interactions facilitate membrane transport
-donor compartment (budding)-> target compartment (fusion) |
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Budding
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New vesicle forms w/ contents selected for transport
-protein coated vesicles-> facilitate the process of budding and deformation of membrane, recruiting i.e. clathrin forms triskeleton- puts together 3 subunits of protein- very rigid Mechanism: -Coat assembly and cargo formation -Clathrin molecules get recruited and force deforming of membrane -Bud formation: Clathrin bind to adaptin (binding sites for cargo receptors)- provides specificity of cargo selection -Vesicle formation- dynamin- protein that mediates pinching off from donor compartment -Uncoating |
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SNARE
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group of proteins that target to different compartments
-can be re-used |
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Vesicle Targetting
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t-SNARE/ v-SNARE (come from vesicles) bind to each other and form alpha helix
-also used for process of lipid bilayer fusion *Used for docking of transport vesicles (first event) |
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Lysosomes
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-Only work in acidic envionment- pH b/w 5 and 6
-materials delivered by phagocytosis, autophagy, receptor-mediated endocytosis |
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Protein Sorting
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Specificity of vesicular transport
-Enzymes can be activated -Mannose-6-phosphate (M6P) enters golgi, binds to M6P receptor, enters lysosome-> removal of phosphate (dissociation at acidic pH)- acts as a safety mechanism M6P- acts a zip code- targets proteins for vesicles that deliver their contents to lysosomes |
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Protein Sorting in Trans Golgi network (TGN)
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Signal-mediated diverson to lysosomes (M6P)
-Signal-mediated diversion to secretory vesicles- for regulated secretion-(package cargo- high conc.- in vesicle- pH dependent) -Constitutive secretory pathway- always occuring |
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Exocytosis
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-Transport vesicles bound for plasma membrane secrete their contents to the outside of the cell
-Vesicle membrane and plasma membrane make contact and fuse -Two sets of lipid bilayers rearrange in a way that exposes the interior of the vesicle to the outside of the cell -i.e. mast cells and horomone producing cells (insulin producing) |
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Endocytosis
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Pinching off of the plasma membrane that results in the uptake of material from the outside of the cell
3 mechanims:Pinocytosis, phagocytosis, receptor-mediated endocytosis |
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Pinocytosis
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- cell drinking- uptake of fluids and small particles via tiny vesicles that form invaginations of the plasma membrane
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Phagocytosis
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-Cell eating- Uptake of large molecules
-very specialized- only phagocytic cells- i.e. white blood cells |
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Receptor-Mediated Endocytosis
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Macromolecules outside the cell bind to membrane proteins that act as receptors
Mechanism: -Vesicle becomes coated- then uncoating occurs -Fusion w/ endosome- sorting occurs in endosome -dissociation of receptor from cargo -Budding off of transport vesicles i.e. entry of LDL into the cell from extra cellular environment |
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Synaptic transmission
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Action potential- triggers release of neurotransmitter
-action potential arrives- triggers entry of Ca 2+ -In response to Ca 2+- synaptic vesicles fuse w/ presynaptic membrane- then release neurotransmitter -Ion channels open when neurotransmitter binds -ion flow causes change in postsynaptic cell potential -Dynamin- wraps around vesicles- pinching off -i.e Botanism-Botox- cleaves the SNARES and prevents neurotransmission |
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Plant ECM
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-Cell Wall- Fiber composites- criss cross of cellulose and pectin fibers-> other sugars involved as well (glycan)- provides ridgity
-Cellulose- polysaccharide- main component -Pectin- another component of plant cell wall- not as strong as cellulose-hydrophilic polysaccharides- waterproofing surface of plasma membrane- i.e. leaves -xylen |
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Animal ECM
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Protein fibers instead of polysaccharide filaments (plant ecm)
-Collagen=most abundant protein -3 imporant parts 1. gel- ground substance 2. structural fibers- i.e. collagen 3. Adhesive elemts- i.e. glycoproteins |
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Tissues
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Organized mixtures of many cell types
-arranged in particular patterns |
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Connective Tissue
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Tissue type in animals made largely of ECM
-padding material- i.e. blood, bone, cartiledge |
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Epithelia
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Tissues that form external and internal surfaces
-Form a layer that separates parts of the body that contain different solutions i.e. urine vs. blood |
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The Gel Components of the ECM
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Sugars- glycosaminoglycan (GAGS)- chain og sugars w/ amino group linked by covalent bonds-many negatively charged groups-sulfate/carboxyl groups
Core proteins- recruit GAGS-i.e. proteoglycan |
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Aggregates (Proteoglycan)
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Very large- several proteoglycans come together. Can be the size of a bacteria
-Neg. charge-makes it osmotically actived- Na + ions drawn in so will draw in water -ability to expand and contract- similiar to sponge- can absorb water Space Filler- resistance to compression -tissue morphogenesis and repair- manipulates ECM, causes swelling- forms gut in embryo |
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Collagen
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Animal specific- every cell has it- i.e. leather, gelatin
Structure: 3 chains that wind around each other to form a triple helix -many collagen triple helixes put together form collagen fibrill- very weak bonds -Many different types- coded by different genes (about 28)- collagen specific proteases- i.e. different for skin, bones, ear, nose- due to difference in structure |
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Fibroblasts
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Cells that make collagen- gives strength to tissue
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Collagen Synthesis
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In ER/Golgi
-synthesis of pro-alpha chain- immature collagen -Hydroxylation -Glycosylation -Self-assembly of 3 pro-chains -Exocytosis out of ER to golgi -Then secretion thorough plasma membrane and pro-collagen will assemble into collagen molecule-more mature due to addition of OH groups to amino acids -Self-assembly into fibril -Aggregation of collagen fibrils to a form a collagen fiber i.e. Scurvy- defects in collagen assembly- Vitamin C needed- OH groups cannot be added to amino acids |
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Adhesive Glycoproteins
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-Fibronectin/Laminin- acts as bridging molecule b/w ECM and collagen molecule
*Multiple binding domains*- will bind to different proteoglycans, cell, collagen -Multi-adhesive proteins- cross- linking components of the basal lamina- provides cushioning and support |
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Basement Membrane
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Very strong- separates underlying tissue and supports cell- acts as barrier- diffusion possible
-important component of laminin -tissue regeneration |
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Integrins
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Trans-membrane protein/ receptor
-integrates cell and ECM via fibronectin and laminin -connected to plasma membrane by actin filaments |
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Integration w/ Cytoskeleton
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Focal Adhesions- Uses actin filaments- concentrated area of integrins- uses actin filaments for cell crawling on substrate (components of ECM)
-always cell to anchor in environment -uses many integrins to give strength- but like velcro- will eventually wear out -important for migrating over a substrate- provides rigidity |
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Parallel array in the ECM
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cells migrate into ECM and become elongated in shape and align parallel- very orderd
-weak adhesion and rolling- selectin dependent -strong adhesion and emigration- integrin dependent |
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Cell-cell adhesion in leukocyte extravasation
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Regulated exocytosis
-Recieves signal- puts out selectin receptor -Binds to p-selectin-> weak interaction -PAF activates integrin-> not all about cell ECM- also used by cell-cell adhesions (mediates)- Stronger affinity than selectins -Firm adhesion via integrin binding -Extravasation (makes its way outside of blood vessel)-> Integrin sends signal to change shape |
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Cadherins
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Mediate cell-cell adhesions
-homophilic- only binds to another cadherin. i.e. N-cadherin to N-cadherin -cell-cell recognition and cell sorting- by type (E-cadherin vs. N-cadherin), also by expression leveles- high vs. low -Ca 2+ dependent |
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Adhesion Belt
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Many cadherins together forming dense array- linked to actin filaments (cell-cell)
Function: Forms tubes- utlilizes contraction and motors w/ associated actin filaments |
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Desmosome
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Uses intermediate filaments instead of actin- very similar to adhesion belts
-structural stability- allows streching |
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Tight Junctions (Occluding Junctions)
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Essentially closes gap between cell
-commonly found in gut -Nutrients able to go through- but barrier to toxins -Only in epitheial cells -Trans-cellular transport across intestinal epithelium - one direction-> drives into blood stream Co-transporter- transport glucose in opposite direction -uses energy from sodium gradient (high conc outside, low inside)- used to drive glucose against its concentration gradient |
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Gap Junctions
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Open gates within adjacent cells
-channels -Size restriction-> up to 1000 Dalton can go through- ions, monomers, nucelotides, amino acids, proteins CANNOT -Connexins- proteins that line gap junctions- many connexins from a channel, where communication happens -Oocyte- support from surrounding cells- gap junctions link nurse cells to oocyte- metabolic and chemical coupling -Closer to basal -Plasmodesmata= gap junction in plant cells |
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Effectors
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Downstream from signals. Cause a cascade of signals- like dominos
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Signal Transduction
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The conversion of a signal from one form to another
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Intracellular signaling proteins
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Target proteins that produce altered metabolism, altered gene expression, and altered cell shape or movement
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Properties of cell-cell signaling
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Amplification: 1 molecule binds to receptor- produces many products
-cascade of enzymes being activated Divergence to multiple targets: 1 signalling molecule activates many enzymes |
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Cell-surface receptor
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Hydrophillic signal molecule on cell surface
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Intracellular Receptors
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Small hydrophobic signal molecule
-receptor in nucleus |
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Steroid Horomones
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Nuclear receptors- intracellular receptors
-have DNA binding domain- like TFs -bind to receptor protein-> conformational change- activates receptor protein -Activated receptor- cortisol complex moves into nucleus -Activated receptor-cortisol complex binds to regulatory region of target gene and activates transcription -Cascade of genes to be transcribed |
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G-protein linked receptors
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Ligand binding region- specificity
-Multipass transmembrane system -Receptor binds to ligand- recruits G-proteins (peripheral)- can readily move within lipid bilayer -activates G-protein by binding to GTP (switch) -When GTP is hydrolyzed to GDP (inactive) -Enzyme activation by G-protein- adenyly cyclase found in plasma membrane (trans-membrane protein)- activated by conformational change -once activated can convert ATP to cAMP (intracellular messenger molecule) |
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Phosphorylation
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Used during signal transduction
-Serine side chain- has OH group-> Phosphat group added facilitated by protein kinase (PKA) uses ATP to make ADP |
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Dephosphorylation
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Protein phosphatase- dephosphorylates- but can still be activated
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Second Messengers
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Non-protein signaling molecules that increase in concentration inside a cell and elicit a response to the received signal
-They are intracellular signals that spread the message carried by the extracellular signal- the horomone |
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Receptor Tyrosine Kinases (RTKs)
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-growth factors
-Can be soluble and found in extracellular space -Can also bind to ECM -Must be activated Mechanisms: -Inactive receptor tyrosine kinase-> signal molecule in form of a dimer (receptor dimerization) -> phosphorylates itself bc tyrosine kinase domains are so close (autophosphorylation) Activation of Ras by RTK- adaptor protein attached to activated RTK recruits proteins that activate Ras |
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Regulation of glucose uptake by insulin
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-Exocytosis
-When glucose levels are high-insulin activated to get glucose into the cell -Insulin-stimulated cells-more transporters- signal binds to insulin receptor and causes relocalization of glucose receptors to plasma membrane to boost glucose uptake into the cell -Can use endocytosis to shut off signal- brings it into the cell |
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Amino Acids
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Amino group (NH2), Carboxyl group (COOH)-> acidic due to highly electronegative oxygens, makes it easy to lose a proton, R side chain- if has OH group, S, NH2 = polar-hydrophillic
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Polymerization
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Process of linking monomers- amino acids polymerize to form proteins
-done so through condensation reactions (dehydration reactions)-loss of water molecule |
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Hydrolysis
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Breaks polymers apart by adding a water molecule
-dominate in comparison to condensation bc it increase entropy and bc it is energentically favorable- lowers the potential energy of the electrons involved |
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Peptide Bond
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C-N bond b/w amino acids due to condensation reactions
-stable bc electrons are partially shared bw the neighboring carbonyl functional group and the peptide bond |
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Polypeptide
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Series of amino acids linked by peptide bonds
Backbone- side chains stick out, it has directionality, and it is flexible left side- amino group- N terminus right side- carboxyl group- C terminus |
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Primary Structure
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Unique sequence of amino acids in a protein (backbone polypeptide chain)
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Secondary Structure
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Folding due to hydrogen bonding that occurs bw the carboxyl oxgyen of one amino acid and the hydrogen on the amino group of another
-Not interactions among side chains but bw amino acids on backbone types: alpha-helix: H-bonds parallel to molecular axis, B-pleated-sheet- sturdier, stronger, H-bonds perpendicular to molecular axis -Large # of H-bonds makes these structures highly stable |
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Tertiary Structure
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Long-range folding due to interactions b/w R-groups or b/w R-groups and the peptide backbone
Interactions: -Disulfide bonds- covalent bonds that form b/w sulfur atoms due to redo reactions bw sulfur containing R-groups (cystein)- referred to as bridges van der Waals interactions: water molecules interact w/ hydrophillic side chains causing the hydrophobic side chains to coalesce- once they hydrophobic side chains become close to each other they are stabilized by such electrical attractions- minute partial charge on one molecule induces an opposite partial chagrge in the nearby molecule causing an attraction - increase stability -Ionic bonds: b/w groups that have full and opposing charges-i.e. ionized amino and carboxyl functional groups -Hydrogen bonds:b/w hydrogen atoms and the carboxyl group in the peptide-bonded backbone and b/w hydrogen and atoms w/ partial negative charges in side chains |
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Quaternary Structure
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Combination of polypeptides as subunits- non-covalent interactions- may be held together by bonds or other interactions among R-groups or sections of their peptide backbones
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Folding
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Spontaneous bc folded molecule is more energetically stable
-facilitated by molecular chaperones -denaturation- unfolding of proteins- disulfide and hydrogen bonds are broken |
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Different types of proteins
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Defense-antibodies
Movement-motor and contractile proteins Catalysis-enzymes-speed up chemical reactions Signaling-Peptide horomones-bind to receptor proteins Structure-Fingernails, hair Transport- |
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Co-factors
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Other molecules that bind to enzyme to make them more active- i.e. Zn+, Mg 2+, other organic molecules (coenzymes)
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Competitive Inhibition
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Molecular that is similar in size and shape to the substrate binds to the active site preventing binding of substrate
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Allosteric Reulation
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A regulatory molecule binds at a location other than the active site- binding changes shape of the enzyme in a way that makes the active site accessible or inacessible- conformational change
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Nucleotide
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A phosphate group (neg charged) covalently linked to 5-carbon sugar arranged in a ring (ribose or deoxyribose)- covalently linked to a nitrogenous base (C,U,T,A,G) w/ the 1' carbon
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Phosphodiester bond
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B/w nucleotides- formed by condensation reaction- joins the 5' carbon on the ribose of one nucleotide to the 3' carbon on the ribose of the other
-Polar- free 5' and 3' phosphate group and sugar on the end |
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Pyrimidines
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Single-ringed base, C,U,T
- no mechanism for pre-biotic synthesis |
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Purines
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Double-ringed base, G,A
-Pre-biotic synthesis possible |
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RNA
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single-stranded-> secondary structure similar to protein- can be hairpin structure- stems and loops- stems- neighboring base-pairing (intra-molecular)
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RNA world
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Autocatlysis: ribozymes-> base-pairing w/ substrate
Evidence: -Central role of different RNA molecules in protein synthesis -Protein synthesis takes place in the absence of DNA, but not RNA -Replicating biological system- such as viroids and RNA viruses -Catalytic and Autocatylic responses of RNA -DNA must be created from enzymes- hard to produce in the cell |
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Polysaccharides
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Polymers that form when monosaccharides are linked together- i.e. glucose
-may be used to store energy in the form of starch or glycogen |
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Monosaccharides
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Simple sugar- carbonyl group and hydroxyl groups
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Glycosidic Bond
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Bond b/w sugar units- always b/w hydroxyl groups-> reactive bond in dissacharide
-formed by condensation reaction -analgous to peptide bonds (proteins) and phosphodiester bonds (nucleotides) -location and geometry can vary widely among polysaccharides unlike the other two which always form at the same location in their monomer |
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Starch
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Alpha-glucose monomers that are joine by glycosidic linkages- branched and unbranched molecules
-used as storage in plants |
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Glycogen
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-storage role in animals- similar to starch in plants
-nearly identical to branched form of starch |
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Cellulose
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major component of the cell wall
-each glucose monomer in the chain is flipped in relation to the adjacent monomer- increase the stability of cellulose strands- due to increased H-bonds |
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Glycoprotein
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Cell recogniton and signaling- protein w/ sugar attached
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Lipid
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Carbon-containing compound that are found in all organism and are largely nonpolar and hydrophobic
3 major classes: steroid, phospholipds, fats |
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Fatty Acid
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Hydrocarbon chain bonded to a carboxyl functional group (hydrophillic head)
Amphipathic- hydrophilic and hydrophobic components |
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Phospholipid
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3 carbon molecule called glycerol that is linked to a phosphate group- gives to polarity w/ a neg charge
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Steroids
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4-ring structure- hydrocarbon chain w/ OH groups- makes it polar
i.e. cholesterol |
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Plasma membrane
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composed primarily of phospholipids and cholesterol
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Phospolipid Bilayer
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-Hydrophilic heads interact w/ water
-Hydrophobic tails interact w/ each other -Thus, nonpolar on inside, polar on outside -sealed compartment -Carbohydrate groups-provide aqueous surface on top of cell -Selective permeability: High permeability- small, non polar molecules Low permeability- large, polar molecules and ions |
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The Fluid Mosaic Model
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-Amphipathic lipids/proteins and membrane structure- peripheral membrane protein
Integral membrane protein (transmembrane)- tightly embedded in bilayer -Dynamic and Fluid |
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Membrane Fluidity
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Unsaturated chain- double bond exists b/w to carbon atoms- cause kinks in phospholipid tails- more fluid bc kinks produce spaces among tightly packed tails- reduce the strength of hydrophobic interactions among the tails
-Saturated fatty acid- more bonding opportunity- less fluid -Length: Longer hydrocarbon chain- less fluid bc hydrophobic interactions become stronger Cholesterol: increase ridgity-goes in between phospholipids- however- can also create disorder providing fluidity |
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Membrane proteins
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anchor- allow cell-cell interaction
-recieves external stimulus-senses environment |
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Membrane Transport
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Combination of size and charge that affect permeability- need transport proteins to facilitate
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Diffusion
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Passive movemet along an electrochemical gradient, through a membrane or a channel- no help needed- high to low concentration
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Facilitated Diffusion
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Passive movement- but facilitated by proteins to make an opening- but still high to low concentration
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Active Transport
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Low concentration to high concentration-> NEEDS ENERGY- thus active movement
-uses phosphate groups from ATP |
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Carrier Protein
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Like a gate-> used for facilitated diffusion + active transport- binds specifically to solute-> conformational change- then opens to other side- VERY SPECIFIC
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Channel Protein
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Open gate w/ aqueous pore- much faster than carrier protein
-also called ion transport bc usually ions that transfer- HIGHLY SELECTIVE |
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ATP
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Great deal of potential energy
- 3 phosphate groups in ATP contain a total of 4 negative charges confined to a small area- thus charges repel each other so large potential energy -When ATP reacts w/ water during a hydrolysis reaction- the bond bw ATP's outermost phosphate group and its neighbor is broken resulting in the formation of ADP and inorganic phosphate- highly exergonic |
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Activated carrier molecule
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Has high energy bond that is readily broken to give off energy, small molecules, able to diffuse and move quickly throughout cell, nucelotide derivatives
i.e. FAD+ 2H++ 2e-->FADH2 NADP+->NADPH- reduced- highest level of energy |
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Glycolysis
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-ATP gives phosphate group to glucose
-Isomerization-> glucose-6-phosphate to fructose-6-phosphate -Phosphorylated again- from ATP molecule-catylzed by enzyme -Allosteric inhibiton by ATP -Splitting of 6 carbon sugar into 2 3-carbon sugars -4 ATP molecules made-> but 2 used- so net of 2 ATP and 2 molecules of pyruvate, 2 NADH |
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Fermentation
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In the absence of electron acceptor- used to produce ATP- uses pyruvate- accepts electrons from NADH and produces lactate
-also pyruvate to make ethanol -ensures glycolysis continues -Recycles NADH to make NAD+ |
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Mitochondria
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MANY-#s depend on need
-Many membranes- increase surface area- double membrane organelle- infolding (cristae) in matrix |
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Pre-Krebs Cycle
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Pyruvate is converted to an acetyl CoA intermediate by pyruvate dehydrogenase
-mediated by 3 enzymes that come together as a large complex- coenzymes-bind to enzyme's active site and stabilize the reaction's transition state -pyruvate- carboxyl group comes off->oxidized to CO2 -Acetyl CoA reacts w/ oxaloacetate to produce citrate |
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Krebs Cycle
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Goal: To oxidize Acetyl CoA to CO2-> 8 steps
-very efficient- can continue to reuse molecules as long as pyruvate is present Net Result: 3 NADH, 1 GTP, 1 FADH2, 2 CO2 |
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Chemiosmotic Theory
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The connection b/w electron transport and ATP generation is indirect- no high energy intermeidate- two seperate steps
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Electron Transport Chain
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Inner membrane of mitochondria
-proteins pump protons (H+) into intermembrane space -strict membrane requirement-H+ pumped from matrix to intermembrane space in 2 different steps -Electrons from NADH and FADH pass through molecules (proteins and Q) with lower electronegativity to one w/ high electronegativity via redox reactions- oxygen= final electron acceptor -proteins are pumped by 3 complexes- Q and cytochome C act as shuttles that transfer electrons between complexes |
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Chemisosmotic Coupling
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Protons pumped into intermembrane space- pH changes from 8-7, creates proton gradient
-ATP synthase acts as a moter- stationary w/ moving parts -H+ travel b/w arm and base on ATP synthase causes conformational change causing the head to rotate producing ATP from ADP -also electrochemical gradient caused by movement of H+- drives ATP synthase |
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Chloroplast
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Outer/Inner membrane
-Thylakoids-vesicle like structures- often occur in interconnected stacks called grana. Space inside a thylakoid is its lumen -Fluid filled space between the thylakoids and the inner membrane is the stroma |
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Chlorophyll
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The most abundant pigment found in the thylakoid membrane
-absorbs blue and red light and reflects green light -two types: a and b |
