Chemical Bonds/Properties of water/pH
What information is provided by the atomic number, what information is provided by the mass number and how are the number of neutrons for an element determined
atomic number tells you the number of protons or electrons.
mass number is the number of protons + number of neutrons.
The number of neutrons is calculated by subtracting the mass number from the atomic number.
1. What are four things all cells have in common
2. Four things different between procaryotic and eukaryotic cells
1. cell membrane, ribosomes, cytoplasm, DNA
2. Pro has no nucleus, only eu has organelles, pro smaller, less complex eu larger more complex, pro divides by binary fission, eu by mitosis, pro one small circular chromosome eu many linear chromosomes, pro anaerobic or aerobic, eu aerobic
What are the three steps in cell signaling and what happens in each step.
1. Reception - ligand (hormone, ion, growth factor) binds to the receptor.
2. Transduction is when binding of the ligand to the receptor protein leads to a series of steps inside the cell where one protein activates or represses another protein in a series.
3. Response - a change in cellular activity ( cell divides or stops dividing, enzyme active or inactive, gene turned on or off, etc.)
Daily Double!!Based on which physical property does agarose gel electrophorese separate DNA
2. 2. What charge does DNA have, why does it have this charge, and in agarose gel electrophorese which electrode will the DNA be attracted to.
1. size
2. Negative charge, due to phosphate group of the nucleotide, attracted to positive (anode).
Provide two reasons why hypoxic tumors are more difficult to treat then normoxic tumors.
1. Most chemotherapy drug need oxygen to work properly, and since there is low oxygen in these regions this impedes these drugs working properly.
2. Since there is poor blood flow in hypoxic regions of tumors, it is difficult to deliver the drug there.
What is the relationship between the number of protons (H+) and hydroxide (OH-) in an acid, base and a neutral substance.
An acid there is more H+, less OH-, in a base less H+ and more OH-. At neutral pH the proportion of H+ and OH- is equal.
1.Describe what happens in the lag, log, stationary, and death phase of bacteria grown in culture.
2. What is the difference between broad spectrum and narrow spectrum antibiotics.
Question 1
Lag phase - bacterial cells getting acclimated to their environment, metabolically active, no increase of the number of cells in the population.
Log Phase- exponential growth of bacterial cells, nutrients are abundant
Stationary Phase - death rate = reproduction rate due to nutrient deprivation, lack of oxygen, changes in pH, waste buildup
Death phase - death rate is greater than reproduction rate due to limiting factors in the environment.
Question 2
Broad spectrum can kill many different species of bacteria, while narrow range can kill only only one particular species of bacteria.
What are the two purposes of second messengers.
1. Amplification of the signal 2. Activate a variety of proteins to elicit multiple cellular responses.
Explain when you clone a gene into a plasmid, after you select bacterial cells that contain the plasmid why do you have to perform screening
To determine if the plasmid self-ligated or if the gene of interest was cloned into the plasmid
Explain in certain cancer cells where multi-drug resistant proteins are located and how they make cancer cells resistant to chemotherapy drugs.
Multi-drug resistant proteins are integral proteins on the cell membrane, and they pump out any chemotherapy drug that enters the cell, therefore drug is not in the cell long enough to cause apoptosis.
Describe in detail an ionic bond, polar covalent bond, hydrogen bond, and a vanderwalls bond.
1. Ionic bond is a transfer of electrons
2. Polar covalent bond electrons shared unequally
3. Nonpolar covalent bond electrons are shared equally.
4. Hydrogen bond between a slightly positive hydrogen atom on one molecule with a slightly negatively charged atom on a different molecule.
Daily Double!!What must happen to a polypeptide in the lumen of the rough ER and if these processes occur where does the protein go next.
Both N-linked glycosylation and chaperones help polypeptide chain to fold into a protein and if folded correctly will travel to the golgi.
Describe the structure of the ECM and what are two functions of the ECM.
ECM is the connection between transmembrame proteins (such as integrin) with proteins outside the cell such as collagen, fibronectin, and proteoglycans. Functions of the ECM are 1. Anchor the cell 2. Cell signaling
If you are using thin-layer chromatography to separate amino acids based on their properties of their R groups and the stationary phase is a silica plate that is polar, while you use a non-polar solvent. The three amino acids you are separating are glycine, phenylalanine, and isoleucine. Isoleucine is the most hydrophobic, while glycine is the least hydrophobic. Which amino acid would migrate the furthest, and which one will migrate intermediate, and which one will migrate the least.
Since glycine is the least hydrophobic it will have the strongest attraction to the polar silica plate and migrate the least, while isoleucine since it is the most hydrophobic will have the weakest attraction to the silica plate and will migrate the furthest,
What is angiogenesis, and what are two reasons why angiogenesis is essential for the growth and development of a tumor.
1. Formation of blood vessels
2. Provides nutrients and oxygen for rapidly growing tumor, and required for metastasis of the tumor.
decrease in protons, buffer will increase protons.
Compare and contrast gram -positive and gram- negative bacteria
2. Explain how you perform gram staining and how does this allow you to distinguish gram-positive and gram- negative bacteria
Both made of peptidoglycan. In gram pos. there is a thick peptidoglycan layer outside the cell membrane. In gram neg. the peptidoglycan layer is thinner and is located between the outer and inner cell membrane, which is unique to gram neg. bacteria.
2. Cells are treated with crystal violet, which will cross both the cell wall and cell membrane and both gram positive and gram neg. will appear violet. Cells are then treated with iodine, which will cross both the cell wall and cell membrane and both gram positive and gram neg. and bind to the crystal violet. Cells are then treated with alcohol which will be able to only penetrate the thinner gram neg. cell wall and then enter across the cell membrane and wash away the crystal violet stain inside the cell. At this point gram positive will still appear violet, while gram neg will now be colorless. Safranin is then applied and gram positive will still appear violet, while gram negative will appear pink.
. Ligand binds to the the receptor and the RTK dimerize.
2. Once the RTK's dimerize autophosphoryl ation of the intracellular domains of the the tyrosine residue on each dimer subunit.
3. The phosphorylated tyrosine's will attract other proteins inside the cell and bind them and activate them by adding a phosphate group to these proteins. Since the phosphorylated RTK attracts many different proteins many different cellular responses are elicited.
Suppose with affinity chromatography after the wash buffer step you find the protein of interest is eluted. Provide two possible scenarios this could of happened.
2. What would be the ideal item to use in the stationary phase in affinity chromatography if you want to isolate one specific protein
1. Wash buffer is too stringent eluted the protein of interest off, protein of interest had a non-specific interaction with the bead/matrix on the stationary phase.
2. An antibody that recognizes the protein of interest.
What are the six hallmarks of cancer
1. Evade tumor suppressors
2. Sustained Cell Signaling
3. Evade apoptosis
4. Replicative immortality
5. Angiogenis
6. Metastasis
Amount of energy required to raise the temperature of a substance by 1 degree celsius.
For warm-blooded animals allows for body temperature homeostasis in a variety of temperatures
For aquatic organisms since water has a higher specific capacity than air, the temperature changes in the body of water will not be as extreme as changes in air temperature.
1. Describe four features a plasmid must have for cloning purposes
2. Describe how conjugation occurs between two bacteria and provide an example how conjugation provides a selection advantage for bacteria
1. Origin of replication - so there are numerous copies of the plasmid int he host cell, therefore there will be ample production of the protein of interest
2. Selection Marker - ex. antibiotic resistance gene so it can be differentiated, which cells were successfully transformed into the host cell.
3. Multiple cloning site (MCS) - a region on the plasmid that contains a vast selection of restriction sites where the gene of interest can be cloned into
4. Promoter - upstream of the gene of interest so RNA polymerase knows where to start transcription
Question 2
The bacteria cell that contains the plasmid is F+, while the bacteria cell that does not contain the plasmid is F-. A pillus connects the F+ and F- bacteria, the plasmid in the F+ bacteria replicates and a copy of the plasmid is transferred from the F+ to the F- converting the F- into a F+. Since a new gene(s) are introduced into the F- this could provide a selection advantage for the F- as it can acquire for an example an antibiotic resistance gene or a gene to make an essential nutrient.
Explain in detail how a G-protein linked receptor is activated.
1. A ligand binds to G-protein linked receptor. 2. When ligand binds to G-protein linked receptor this results in a conformation change that will result in the G-protein receptor will bind to the G protein and cause the G protein to exchange GDP for GTP. 3. When the G protein is bound to GTP it is active and activate enzymes that will produce second messengers such as cyclic AMP, IP3 which will cause Ca+2 from smooth ER which CA+2 act as a second messenger, DAG that will allow an amplification of the signal and activation of a lot of different proteins to elicit an array of responses
If you are doing ion exchange chromatography and you want to perform cation exchange the proteins of interest have a Pi 7 and 9, What pH must the equilibration buffer be.
2. If you wanted to separate three different proteins: Protein A has a pI of 5, Protein B has a pI of 7 and Protein C has a pI of 8.5. If these proteins were mixed in a buffer that is 8 which of these protein(s) could you use anion exchange chromatography to separate
1. The pH of the buffer must be less that pH 7 so the proteins will have a positive charge.
2. Protein A and protein B because they would have a negative charge
In MM describe which cells overproliferate and what are the complications that result from this
Over-production of one antibody subtype instead of production of various sub-types ( for example all the plasma cells in a MM patient might only produce IgA sub-type, but not IgE, IgD, IgG, or IgM) therefore this can lead to a compromised immune system.
•Over-production of misfolded light chains can lead to AL ( antibody light chain) amyloidosis which can result in these misfolded light chains to aggregate and go into circulation and damage organs such as: heart, kidney, GI tract, and liver.
•Over-proliferation of MM cells crowd out and impair production of healthy red blood cells, white blood cells and platelets in the bone marrow.