Chemical Bonds and Properties of Water and pH
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.
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 two main phases of the cell cycle, which phase does the cell spend majority of time in, and what are some key events that occur in those two phases.
. Interphase and Mitosis
2. Cell spends majority of time during interphase.
3. During interphase cell grows in size, makes proteins, replicates it's DNA. Mitosis cell divides in that each daughter is identical with an equal distribution of the DNA
1. 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).
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
Describe how a hydrogen bond forms between two water molecules, and how many hydrogen bonds does water form.
Between the slightly positive hydrogen on one water molecule and the slightly negative oxygen on another water molecule. Each water molecule can form a hydrogen bond with four other water molecules.
Describe three ways to increase the fluidity of a cell membrane.
decrease both cholesterol and saturated fatty acids, increase unsaturated fatty acids.
Daily Double-Explain how proto-oncogenes and tumor suppressors regulate cell division in normal cells, and explain how the dysregulation of these genes can lead to cancer.
Proto-oncogenes promote cell division, while tumor suppressors stop cell division. In normal cells there is a balance between the two. In cancer cells proto-oncogenes mutate into oncogenes, therefore promoting uncontrolled cell division, while tumor suppressors are mutated and as a result there is no signal for the cell to stop dividing.
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 are these three functional groups.
aldehyde, hydroxyl, sulfhydryl
decrease in protons, buffer will increase protons.
Dailly 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.
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.)
1. Explain the purpose of the Calcium chloride and the heat shock in a bacterial transformation.
2. If you transform a bacteria strain that is both ampicillin and kanamycin sensitive with a plasmid that contains a kanamycin resistance gene explain if it will grow or die on the following plates
A. LB w/o antibiotics
B. LB + AMP
C. LB + Kan
D. LB + AMP + Kan
1. Positive charge Calcium ion shields the negative charged DNA, heat shock opens up the cell membrane so the plasmid can enter the cell.
2. A. survive because plate contains no antibiotics
B. Die because plasmid only contains Kan resistance gene, will there fore still be sensitive to AMP
C. Survive because plasmid contains a Kan resistance gene
D. Die because plasmid only contains Kan resistance gene, will there fore still be sensitive to AMP
Compare and Contrast competitive and Non-competitive inhibitor
Competitive inhibitors mimic the substrate and both have an affinity for the active site. These are reversible by adding more substrate.
Non-competitive inhibitors bind outside the active site, therefore denaturing the enzyme. These are irreversible.
Potassium has an atomic number of 19 and a mass number of 39. How many electrons, protons, neutrons does potassium have. How many electrons are in each orbital, and how many chemical bonds does potassium form.
Potassium has 19 electrons, 19 protons, 20 neutrons.
2 electrons in 1st orbital, 8 electrons in second orbital, 8 electrons in third orbital, 1 electron in 4th orbital.
3. 1 chemical bond
Describe in detail the modifications and how the Golgi determines the final destination of a protein
1.Protein travels from rough to cis golgi, where modification of N-linked glycosylation occurs
2. O-linked glycosylation occurs in medial golgi
3. Trans golgi determines the destination of the protein, if a mannose-6 phosphate is added to the protein it will go to the lysosome, if not then woll be secreted out of the cell
1. 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.
If you wanted to prepare 500 mL 1 XTBE that is required to make both the running buffer and to prepare the gel and the stock is 20 X how would you prepare this dilution?
2.Explain how you would prepare a 1.5 % agarose gel in a total volume of 40 mL
1. Add 25 mL of 20 X TBE to 475 mL of distilled water to make a final 1 X concentration
2.Dissolve .6 grams of agarose in 60 mL of 1X TBE buffer
Compare and contrast type i and type 2 diabetes
ype I is an autoimmune disease that results in death of beta cells, therefore decrease insulin production. As a result less glucose delivered into cells and hyperglycemia. Cells use fats as an energy source that will produce ketone bodies that will eventually cause ketoacidiosis.
Type II insulin receptors are resistant to insulin. Since cells are not responding to insulin, beta cells think they need to produce more insulin. Eventually Beta cells are overworked resulting in apoptosis of the beta cells, therefore less insulin prodiced.
Both result in hyperglycemia and ketoacidiosis.
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 five ways antibiotics kill bacteria
2. Describe five ways bacteria become resistant to antibiotics
Question 1
1.Inhibition of cell wall synthesis
2.Breakdown of the cell membrane structure or function
3.Interference with functions of DNA and RNA
4.Inhibition of protein synthesis
5.Blockage of key metabolic pathways
Question 2
1. Drug inactivation
2. Decreased permeability
3. Drug is pumped out of the cell
4. Change in binding site
5. Use an alternative pathway
Provide five treatment scenarios for targeting the AR in prostate cancer
Castration to remove testosterone.
•Inhibit the enzyme that inhibits the conversion of testosterone into DHT.
•
•Competitive inhibitor to prevent DHT from binding to AR.
•Design a drug that will target the over-active AR to the proteasome.
•Prevent the AR receptor from entering the nucleus.
•Prevent the AR from binding to it’s target genes so those genes cannot express the proteins for cell proliferation
1. 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
What is the difference at the genetic level between the normal and mutant huntington gene.
2. What does CAG code for
3. Explain why the mutant huntingtin protein tends to form aggregates and why these aggregates are toxic to the cell.
1.Normal huntington gene has less then 35 CAG repeats, mutated one has 35 or more
2. CAG codes for glutamine
3. Proteins with poly-glutamine stretches tend to have a rich B-sheet secondary structure which tend form aggregates. These aggregates are toxic to cells because they tend to sequester other proteins that are required for the normal homeostasis of the cell, therefore this will lead to apoptosis.