DNA replication - Houston Independent School District



2013 Fall final holy pages: Not exclusively included. Please go to my final review and go to the check list, study one item at a time. these will help:BiochemistrySubstrate binds to enzymes by weak interaction not covalent bonds, H-bonds etc.Amylase digests carbohydrates (starch) to simple sugars (glucose, fructose etc). Human have alpha amylase which digests starch. Cows have beta amylase that digests cellulose.Rate of enzyme reaction= change of substrate with time, or change of product with time. The slope is the rate.The initial rate is linear, and logistic afterwards due to substrate concentration decreases.Bell shaped curves for Rate vs pH or Rate vs Temp. The decline is caused by enzyme denaturation (not degradation or dead)More enzymes, higher the slope on the rate curveNH2 is the amino group, COOH is the acidic group. Primary structure for protein: the amino acids sequence, bound by covalent bonds, named peptide bonds. (AAn, formed by dehydration, losing n-1 water.)Secondary structure caused by H-bonding intramolecularly ( helix and sheet)Tertiary structure caused by H-bonds and S-S bonds intermolecularly.quaternary structure caused by dimerization of the same peptides (two of the same bound together by vanderwall, H-bonds, S-S bond, anything except covalent); or trimers or tetramers.Know the structure of the neutral fats: triglycerides (3 fatty acids bound by glycerol) high energy molecules b/c they have a lot of hydrogens. Phospholipids have two fatty acids and highly charged on the phosphate. They are in phospholipid bilayer (cell membrane).Know the structure of steriod (fused rings): sex hormones, cholesterol etc.Know the structure of ATP and last (outtermost) phosphate bonds are high-energy.Cell and trasportknow these organells: ribosomes, mitochodria, lysosomes, Golgi, rough and smooth ER (roung makes proteins; smooth makes lipids.)Prokaryotes have no membraneous organells. Nucleus is one of them. Ribosome is not membraneous. Prokaryotes, also known as bacteria, have ribosomes. All cells have cell membranes.Know Nucleolus which is a compartment inside the nucleus and make ribosomes and rRNA and all RNA. RNA are made inside the nucleus.Bulk transport: phago (solid), pino( water), endo, exo-cytosis.Mitochondria is for cell respiration only.Chloroplast is for making only glucose. Know your endosymbiosis theory: Circular DNA, rRNA, makes its own proteins, the same size as bacteria, Nephron uses facilliated diffusion (no energy needed )and active transport (needs energy), regulated by hormones (ADH and aquaporins)All pumps (proton, sodium, potassium) are active transports.Gluose diffuses into cells by faciliated diffusion.Chemiosmosis involves the movement of H+ across a enzyme complex called ATP synthase (turbine). The force move the H+ is due to a concentration gradient and an elctrochemical gradient. H+ has a possitive charge and the outside of the thylakoid is negative.Osmosis is the movement of water across a membrane due to differences in solute concentration or water potential.DNA replicationThe goal is to make identical DNA. Double the amount.DNA polymerase is an enzyme that base pairs a nucleotide with a nucleotide that is complementary to it. (A to T, G to C)Helicases are enzymes that unwind the DNA molecule into single strands of DNADuring DNA replication hydrogen bonds between nitrogenous bases are broken not the sugar-phosphate bond of each strand.A phosphodiester bond is a bond between two nucleotides linking 2 deoxyribose. It connects a phosphate group of one nucleotide and connects to the next nucleotide at the three prime end.No enzymes are needed to form the hydrogen bonds as they form when the DNA polymerase pairs the DNA nucleotides.DNA replication is semi-conservative: a new strand is made on top of a old strand. It is also anti-parallel.Know your repliaton fork.32P radioactive labels DNA (phosphate), 35S labels proteins.A mutation is a change in the DNA sequence of a geneDNA doubles in S phase. (part of interphase)nuclear membrane breaks down during prophase of mitosis.apical meristem is where mitosis is occurring.Mitosis is to make identical cellsCancer cells are cells that have uncontrolled mitosis or cell division.PhotosynthesisKnow the lab: bromophenol blue is bleached by oxygen. So we can use it as an indicator for photosynthesis (oxgygen released). LDR (light dependent reaction) releases oxygen (byproduct) and the hotties NADPH and ATP. The hotties are used to power the Calvin cycle. The oxygen comes from splitting the water. Chemiosmosis happens with the H+ built up and diffuse through the protein channel of ATP synthase to make ATP.Cyclic electron flow only happens in Photosystem I and makes more ATP but not NADPH. No oxygen is produced either.The pigments are chlorophylls (absorb red and blue lights, not green) and carotennoids (only blue ight). Electron from the Mg in the porphyrin jumps to higher excited state and was accepted in the reaction center. The electrons released from the split of water supplement the loss of that electron.Calvin cycle: a carbon fixation cyclic process: CO2 bond with the two timer (RubP) which is 5-C, with the enzyme Rubisco to make a 6 C compound which splits right away into two 3-C compounds. Wtih ATP and NADPH, the 3-C compound turns into 6 G-3-P. One G-3-P (or called PGAL) leaves the chloroplast and form dimer to make one glucose (6C compound). The rest of the 5 cycles back to become RuBP again with ATP.Photorespiration: Stomata close during hot and sunny day to conserve water. Thereby short of CO2 and a rise of O2. All the RuBP are converted to respiration because the Rubisco enzyme is not specific to CO2. O2 binds to RuBP and losing the 5-C compound and therefore energy. Photorespiration does not make ATP unlike respiration.C4 adaptation (spatial): CO2 binds to PEP ( a 3 C compound) in the mesophyll and form a 4 C compound. As it reaches the bundle sheath cells, it breaks down to CO2 and a pyruvate ( 3C compound). The CO2 is released and goes into Calvin cycle.CAM adaptation (temporal): CO2 binds to organic acid CAM at night and release CO2 at night. Then CO2 can be used at night for the Calvin cycle to make sugar.RespirationStudy the comparison of Chemiosmosis in chloroplasts and mitochondria. Text p188.All cells have the biochemical pathway glycolysis, which would make it a very ancient biochemical pathway. Not all cells have the Krebs cycle and the electron transport chain. In terms of evolution, glycolysis (anaerobic respiartion) is probably more ancient than aerobic respriation. ( Glycolysis occurs in the cytoplasm ). Glycolysis: splitting glucose into two pyruvate (3C compound) in the cytosol.Fermentation only nets two molecules of ATP compared to approximately 36 in aerobic respiration, which oxidizes glucose to 6 molecules of carbon dioxide and 6 molecules of waterOxygen is used in cellular respiration (metabolism) as the final electron acceptor at the end of the electron transport chain.The electrons originate from either NADH or FADH in the electron transport chainthe pH is lowered and a proton gradient is established where there are more electrons in the outer compartment of the membrane than in the inner compartment. The outer compartment is positive relative to the inner compartment.Aerobic respiration is considered to be more efficient as it results in many more molecules of ATP (approximately 36 ATP) than fermentation (2 ATP).-Carbon dioxide is formed in the Kreb’s cycle.-Carbon dioxide does not combine with lactic acid to form pyruvic acid.-Oxygen does not catalyze the glycolysis reactionThe more hydrogen an organic molecule has, in general, the more energy it will contain.In general the smaller the endothermic animal, the greater their need for energy and increased cellular respiration.The rattlesnake will have the slowest rate of respiration because it is a ectotherm and does not produce heat to maintain a constant body temperature.Negative feedback occurs when one of the products of a biochemical pathway is an inhibitor or negative modulator for one of enzymes in the pathway.Protein Synthesis and Gene ExpressionA plasmid is small circle of DNA found in prokaryotic cells. It is smaller than the bacterial chromosome.During development, individual cells of the same organism begin to produce different proteins because specific genes are activated in the cell. This is called cell differentiation.transcription is to makes mRNA from a DNA geneAn operon is found in prokaryotic cells. It is a series of genes found in close proximity to one another. They are controlled by repressor proteins. Trp operon is operated by negative feedback (the product, trp, activates the inactive repressor) to slow down synthesis; lac operon is positive feedback. (it inactivate the repressor so that more product will be synthesized)Histones are found only in eukaryotic cells not prokaryotic cells.Reverse transcription is using RNA as a template and making a DNA molecule.Only about 10% of the human genome is transcribe and translated.In eukaryotic cells unlike prokaryotic cells, genes for related function, are often located on different chromosomes. They do not share the same promoter and operateor regions.Frame shift mutation: changing the subsequent genetic codes of the sequence is most detrimental.Both DNA and RNA uses phosphate groups and neither one uses sulfate groups.A codon consist three nucleotides that specify an amino acid. There are four nucleotides so 4 x 4 x 4 = 64 combinations or codons.Transcription occurs in the nucleus; Proteins are made in the cytoplasm (translation);mRNA is made in the nucleus and determines the sequence of amino acids of a protein made in the cytoplasmGTP is the energy used during translationThe enzyme that connects the right amino acid to the specific t-RNA is aminoacyl-tRNA synthetase. There are 21 amino acids, therefore 21 of these enzymes.The process of the ribosome moving from one tRNA to another during process of making a polypeptide chain is called translocation.Learn to read the codon chart, from left to right.Genetics You need to study my special genetics review packet as on my hw page: Signal Transduction and any other ones: LTF packets. ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download