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Components: Regulatory gene Lac I, Strugtural genes lac z, lac y, lac A, promoters and an operator
Lactose
Beta-Galactosidase: breaks down lactose to galactose and glucose
When glucose is present
production of cAMP is blocked. The operon is off
When lactose is present:
lactose repressor binds to it, which allows CAP activator to bind to it and facillitate transcription
A release factor binds to the A site of the ribosome complex and the growing polypeptide chain is free
The traslation initiation complex in the ribosomes dissociates using GTP.
Translocation in the E site: the tRna in the P site is moved to the E site
Peptide Bond Formation (P site): forms between the carboxyl end of polypeptide chain in P-site and the amino group of the A site. Pep bond catalyzed by peptidyl transferase
Codon recognition in the A site: anticodon of tRna pairs up with mRna in the A site
Eukaryotes amino acid is Met
Prokaryotes amino acid is Formal Met
Three models hypothesized: conservative (parental strands reassociate after replication), semi-conservative (strands separate and act as templates for complementary strands), Dispersive (part of the parent strand is mixed in the daughter strands)
Experiment found the solution had an intermediate strip and low density strip
confirmed semiconservative model.
Found that something (genetic material) was transferred from the dead S strain to the living R strain.
Discovered DNA carried genetic material
DNA bending protein brings the activators closer to the promoter and TATA box.
General and Mediator transcription factors
General transcription factors and mediator proteins bind the activators.
RNA Polymerase II
RNA polymerase II binds the promoter and the gene has Increased Expression.
adds bases to daughter strand in the 5' to 3' direction
DNA Polymerase I
kicks off primers from the RNA
Ligase: final step/ enzyme connects okazaki fragments (lagging strands)
DNA Polymerase III
adds nucleotides to the 3' end on the leading stand and the RNA primers on the lagging strand
Primase: creates RNA primers that attach to DNA
helicase: separates the two strands of DNA (breaks H bond)
Topoisomerase: ensures that the DNA strand is not strained and knotted.
SSB: ensures that the single strands do not recombine
Pre-mRNA is formed: we get a poly-A tail which helps with the RNA's stability and we have a 5' cap which helps us with Translation later on.
Spliceosomes help remove introns leaving exons.
Alternate splicing: allows the expression of certain proteins over others.
exons: the coding nucleotides that will be expressed (different ways of splicing = different proteins)
introns: separate the coding nucleotides that will be expressed.
The process is done at this point RNA is made w/out processing
Rubisco
3x Short-lived intermediate
6x 3-phosphoglycerate
6x 1,3 bisphosphoglycerate
6x Glyceraldehyde 3 Phosphate (G3P),
3x Ribulose bisphosphate
1 G3P
Photosystem II
These electrons get sent to the electron transport chain.
Electron Transport Chain
Photosystem I
ferredoxin (Fd)
NADP+ reductase
NADPH+
Light (photons) hit the chlorophyll in the light harvesting complex.
This excites the photons and then they return to ground state and the energy jumps between them until they reach the main chlorophyll a in the reaction center complex.
These main chlorophyll a get excited but instead of returning to ground state, these are captured by the primary electron acceptor.
These electrons are sent outside of photosystem I to Fd
Plastoquinone (Pq),
Cytochrome Complex
Plastocyanin (Pc)
ATP Synthase
ATP
Subtopic
Endergonic: energy is required, energy is absorbed
Spontaneous reaction: free energy is negative
Signal binds to the receptor, changes its shape and activates the receptor
Active Receptor travels into the nucleus and binds to DNA
Transcription occurs which produces mRNA
mRNA leaves the nucleus, ribosomes bind and translation occurs, producing a protein.
GCPR binds to G protein, bound by GTP, which activates the G protein
Activated G protein binds to the adenylyl cyclase. GTP hydrolyzes which activates adenylyl cyclase and changes its shape.
Adenylyl cyclase converts ATP to cAMP
cAMP activates pka which leads to cell response
A regulatory molecule binds to the allosteric site of an enzyme an locks it in its active form. Substrates can bind.
A regulatory molecule binds to the allosteric site of an enzyme an locks it in its in-active form. Substrates can't bind.
An inhibitor binds to a site other than the allosteric site, and changes teh enzyme's shape. Even if the substrate binds the active site, the ezyme no longer works.
An inhibitor binds to the active site of an enzyme. This doesn't allow for the substrate to bind and it stops the enzyme for functioning.
Lactic Acid Fermentation
Outputs: Lactate, NAD+
Alchohol Fermentation
Inputs: 2 Pyruvate, NADH
Outputs: Ethanol NAD+
Inputs: 1 glucose, 2 ATP
Step 1: glucose binds to hexokinase and with ATP becomes G6P.
Step 2: G6P becomes F6P
Step 3: F6P binds to the phospho-fructo-kinase enzyme and with ATP becomes fructose 1,6 bi-phosphate
Step 4 + 5: That fructose 1,6 biphosphate becomes 2 G3P
pyruvate oxidation
Inputs: 2 pyruvate
Products: 2 Acetyl CoA, 2 Co2, 2 NADH
Citric Acid Cycle
Inputs: Acetyl CoA
Step 1: Oxaloacitate goes to an enzyme and with Acetyl CoA becomes Citrate.
Step 2: Citrate becomes Isocitrate.
Step 3: Isocitrate becomes alpha ketogluta and NADH is released.
Other Steps: 2 NADH, ATP, FADH are formed.
Products: 1 ATP, 3 NADH, 1 FADH
Oxidative Phosphorelation
Inputs: 10 NADH, 2 FADH
Electron Transport Chain:
Cyt c
Q
Complex I
NADH transfers electrons to complex I
Complex II
FADH2 transfers electrons to complex II
Complex IV
O2 + H+ = H20
Outputs: H2O, about 26 - 28 ATP
Complex III
Chemosmosis
ATP Synthase
Here, H+ in the intermembrane space, go back down their concentration gradient. This energy is used to add an inorganic phosphate to ADP to form ATP
helps regulated fluidity when too rigid or too fluid
Unsaturated fats
higher diffusion+ fluid
saturated fats
lower diffusion+ rigid
Temperature
lower temp= rigid
high temp= fluid
small, nonpolar > small, uncharged polar > large, uncharged polar > ions
when active transport indirectly transport of another
sucrose/H+: H+ drives sucrose in when H+ is pumped out of the cell and a gradient is created
Uses energy to transport solute against its concentration gradient
electrogenic pump
Phases:
Resting State: na and k voltage gated pumps are closed
Depolartization: Na pump opens allowing Na to flow in making it less negative (if this hits a threshold it moves on to the rising phase)
Rising Phase: cell becomes positive while K pumps are still closed until action potential is reached
Falling Phase: Some k pumps open while na pumps close making the cell overall negative
Undershoot: the cell uses na/k pump to help return it to the resting phase.
creates a charge gradience generating voltage across a membrane
Na/K Pump
2 K+ in 3 Na+ out
Cells are slightly - because there are fewer positive charges in the cell
1. 3 Na in the cytoplasm bind to the pump
2. phosphorylation via kinase triggered (PO4 attaches to the pump)
3. Pump changes shape and releases Na+ out
4. 2 K+ outside the cell attach to the pump while removing PO4
5. pump returns to its original shape
6. K+ comes off the pump and the cycle repeats
Proton Pump
Use vesicles to transport large molecules. membrane stretches to engulf particles
exocytosis
cell ejects substances
endocytosis
cell takes in substances
receptor mediated
uses receptors and ligands to take in molecules
pinocytosis
takes in fluids
phagocytosis
takes in "food" particles
uses proteins and other channels to aid passive diffusion
Carrier proteins
changes shape to move solute
Channels
channel that allows water/solute to enter (no shape change)
Ion Channels
gated
voltage
opens/ closes when membrane potential changes
ligand
opens/closes when ligand binds to a receptor
stretch
opens/closes when deformed
ungated
constantly openn
diffusion down a concentration gradient w/out using energy
Hypertonic sol.
relatively higher concentration compared to the cell
Plant: Plasmolyzed animal: shriveled
Isotonic sol.
same concentration as the cells
Plant: Flaccid animal: normal (ideal)
hypotonic sol.
relatively lower concentration compared to the cell
Plants: turgid (ideal) animal: lysed
4 fused carbon rings
Hormones
Cholesterol
Low-Density Lipoprotein
deposits extra cholesterol in blood cells which can lead to plaque buildup.
High-Density Lipoprotein
helps remove excess cholesterol by taking it to the liver for excretion
Function
forms phospholipid bilayers in cell membrane
amphipathic
phosphate group
2 fatty acids
glycogen
fatty acids (3)
Unsaturated
liquid at room temp.
double bonds
Saturated
solid at room temp.
No double bonds
Glycerol
Structural
Cellulose
linear structure
b (1,4) glycosidic linkages
No branching
Storage
Glycogen (animals)
Extensively Branched
Starch (plants)
Amylopectin
a (1,4), a (1,6) glycosidic linkages
Branched
Amylose
helical structure
a (1,4) glycosidic linkages
Unbranched
Maltose(glucose+glucose)
Lactose (glucose+galactose)
Sucrose (glucose+fructose)
Aldoses
Ketoses
Trioses (3C)
Pentoses (5C)
Hexoses (6C)
Quatenary
multiple tertiary protiens
Tertiary
Disulfide Bonds
R group interactions
Secondary
H-Bonds
Alpha + Beta Structures
Primary
Amino Acids
Peptide Bonds
Nucleic Acids
Phosphate Group
Nitrogenous Base
RNA
U
DNA
A,T,C,G
Pentane Sugar
Ribose=RNA
Deoxyribose=DNA
DNA= 2x strand RNA= 1 strand
Phosphodiester Linkage (5,3)
Nucleus
Chromatin
Nucleolus
Nuclear Envelope
Endoplasmic Reticulum
Rough ER
Smooth ER
Cytoskeleton
microtubules
microfilaments
Golgi Apparatus
responsible for the synthesis and secretion of a cells products
Plasma Membrane
Mitochondria
where cellular respiration occurs and ATP is generated
Cell Wall
maintains cell shape and protects cells from mechanical damage
Central Vacuole
used for storage, breaking down waste & hydrolysis of macromolecules
Plasmodesmata
channels through cell walls that connects the cytoplasm of adjacent cells
Chloroplast
converts energy of sunlight to chemical energy stored in sugar cells
Lysosomes
Where macromolecules are hydrolized
Centrosome
region where microtubules are initiated
Components
Fimbrae
Cell Wall
Flagellum
Plasma Membranes
Ribosomes
Nucleoid
Extremophiles
Extreme Halophiles
methanogens
Extreme thermophiles
Electronegativity
<2.5
nonpolar
>2.5
Polar
Hydrophobic/Hydrophilic Interactions
High Surface Tension
Universal Solvent
High Specific Heat
Expands when Freezing
Denser as a liquid
High Heat of vaporization
A repulsive interaction between water and non-polar molecules. The non-polar molecules will cluster together and be surrounded by water.
A weak force that attracts non-polar atoms (this is distant dependent) and LDF's (a form where temporary dipoles form and attract other molecules) is a sub-category
A form of Dipole-Dipole interaction between hydrogen and one following from another molecule (F, O, N)
an Ion is attracted to the oppositely charged side of a polar molecule (water's oxygen atom and Na+ ion)
when 2 polar atoms have polarity and the positive end of one atom is attracted to the negative end of another
