MCAT June 13
diamagnetic, paramagnetic
(diamagnetic/paramegnetic) material will be repelled by an external magnetic field, but (diamagnetic/paramagnetic) material will be attracted by an external magnetic field
Na+ reabsorption from the filtrate is very important to the function of the loop of Henle (ascending) in the nephron of the kidney, so these cells are very dependent on the sodium pump
A cell in which structure of the body would be expected to have especially active sodium pumps?
drop
According to the Doppler effect, the observed frequency (frequency at the detector) should _________ when the object is moving away from the detector
Acetic acid is a weak acid
Acetic acid is a (weak/strong) (acid/base)
low Because the excess Na+ would need to be excreted in urine, aldosterone would not be needed to reabsorb Na+
Aldosterone causes Na+ reabsorption by the kidney tubules. After ingesting a large amount of NaCl, aldosterone levels would be expected to be _________
decrease The binding of hydrogen ions to a molecule of oxyhemoglobin enhances the release of oxygen (decreases hemoglobin saturation)
An increase in the concentration of hydrogen ions will __________ hemoglobin's affinity for oxygen
These are examples of the stage of formal operation, which develops around age 12
At what stage of Piaget's stages of cognitive development are children able to manipulate abstract symbols to solve puzzles and problems and engage in counterfactual thinking and be able to image new realities?
liver, gallbladder
Bile is produced by the _________ and stored in the __________
extracellular (not inside of cells)
Blood plasma and lymph are both __________ fluids
Absolute pressure is the sum of all pressures at a certain point within a fluid; it is equal to the pressure at the surface of the fluid (usually atmospheric pressure) plus the pressure due to the fluid itself (gauge pressure) Gauge pressure is the name for the difference between absolute pressure and atmospheric pressure. In liquids, gauge pressure is caused by the weight of the liquid above the point of measurement
Compare absolute and gauge pressure of a fluid
Coenzymes are small, non-protein organic molecules that carry chemical groups between enzymes. They assist with biological transformations and examples include vitamins, biotin, and coenzyme A. Cofactors are non-protein chemical compounds that bind to enzymes or other protein molecules. These are inorganic chemical compounds that aid the function of an enzyme by helping increase the rate of the reaction which the enzyme is catalyzing. They can only be removed by denaturing the enzyme and examples include metal ions like Zn2+, K+, and Mg2+.
Compare coenzymes and cofactors
Fluid intelligence: ability to quickly identify relationships and connections, and then use those relationships and connections to make correct deductions. This peaks in early adulthood. Crystallized intelligence: cognitive capacity to understand relationships or solve problems using information acquired during schooling or other experiences. Peaks in middle adulthood.
Compare fluid and crystallized intelligence
These are ring conformations of monosaccharides such as glucose. Furanose is a five-membered ring (4 carbons and 1 oxygen) and pyranose is a six-membered ring (5 carbons and 1 oxygen)
Compare furanose and pyranose
Phosphatase enzymes remove phosphate groups from their substrate Phosphorylase enzymes catalyze the addition of a phosphate group from an inorganic phosphate (P + H) to an acceptor Kinase enzymes catalyze the transfer of a phosphate from ATP to a specified molecule
Compare kinase, phosphatase and phosphorylase enzymes
Osteoclasts break down bones, increasing blood calcium levels Osteoblasts form bone
Compare osteoclasts and osteoblasts
Positive sense RNA viruses' genetic material is mRNA that can be readily translated into proteins in the host cell Negative sense RNA viruses' genetic material is the antisense of the viral mRNA. Genetic material must be transcribed into positive sense RNA by RNA polymerase before translation.
Compare positive and negative sense RNA viruses
Proactive social movements promote a social change, while reactive social movements resist a change
Compare proactive and reactive social movements
Tautomerism is actually moving around bonds while resonance is only moving around electrons. Resonance does not change the positions of atoms, while tautomerism does. Resonance structures are not actually two different structures, and it is more accurate to draw them with dashed lines because the molecule isn't exactly one structure or the other, but shows characteristics of both. Resonance provides stability to molecules. Tautomers are a type of constitutional isomers that exist in equilibrium. This is commonly seen with keto-enols ( R-C=O interconverts to and from R=C-OH ). This forms real, distinct molecules as alpha-hydrogens move around. Does not necessarily have an effect on the stability of the molecule.
Compare resonance and tautomerism
The *regulator gene* codes for the repressor. The *promoter gene* is the site of binding for RNA polymerase. The *operator gene* is the binding site for the repressor. The *structural gene* encodes for the desired protein.
Compare the function of the following in the regulation of gene transcription: operator gene, structural gene, regulator gene, promotor gene
The strand of DNA not used as a template for transcription is called the coding strand (also known as the sense strand), because it corresponds to the same sequence as the mRNA that will contain the codon sequences necessary to build proteins. The template strand is the DNA strand that mRNA is built from.
Compare the template and coding strand of a gene
its volume would be less than that expected by the ideal gas law because of attractive molecular forces pulling its molecules together. The reason for this is that one of the assumptions made by the ideal gas law is that gases have no intermolecular forces
Compared to what would be predicted by the ideal gas law, when a real gas is subjected to moderately high pressures, its volume _________________
Bridges between actin and myosin form, break, and re-form, leading to a shortening of muscle sarcomeres. According to the sliding filament model, neural impulses cause the release of calcium which binds to troponin, a molecule that along with tropomyosin, blocks the binding sites for myosin on actin molecules. This calcium-binding to troponin causes a shift in the troponin/tropomyosin complex, revealing the binding site for myosin. Myosin then binds to actin, causing a conformational change in myosin that "cocks" the head of the myosin molecules and slides the actin filament. ATP binds to myosin, causing it to detach from actin and "recharge" (rebend again). If another binding site is available on actin, myosin will bind again and slide the actin filament even further.
Describe the role of actin and myosin in muscular contraction based on the sliding filament model
180 degrees This is because the difference corresponding to a half of a wave is 180 degrees, and half a wave difference in phase between two eaves corresponds to destructive interference
Destructive interference occurs when light rays take paths that differ in phase by _____ degrees
alternative splicing (generating transcripts with different combinations of exons)
Different protein *isoforms* are synthesized from the same gene through ________________
A cognitive-behavioral therapist would see the causes of a disorder as stemming from the interactions between thoughts and behaviors. Their treatment approach to disorders such as phobias would most likely include correcting patterns of conscious thought (such as presenting the feared thing to the patient and challenging the patient's belief that it is harmful)
Explain the cognitive-behavioral therapy approach
Potency is a measure of activity expressed in terms of the amount required to produce an effect of a given intensity. For example, if strain A needs 4 cells to cause infection and strain B needs 2 cells, then strain B is twice as potent as strain A
Explain what potency is in terms of drugs or other things acting on the body
Free radical scavengers (ex: NAC) mitigate the effects of reactive oxygen species (ROS)
Free radical scavengers mitigate the effects of what?
negative
Gram-__________ bacteria have a thin cell wall composed of peptidoglycan and an outer membrane containing phospholipids and lipopolysaccharides
positive
Gram-__________ bacteria have cell walls composed of peptidoglycan and lipoteichoic acid. They turn purple during Gram staining.
nucleophiles Grignard reactions form new C-C bonds and creates secondary/tertiary alcohols from aldehydes or ketones
Grignard reagents are good (nucleophiles/electrophiles)
For a compound with an sp3 hybridized central atom, the more non-bonding electron pairs, the smaller the angle
How are bond angles related to electron pairs?
Fb = p_fluid gV The buoyant force is directly proportional to the volume of fluid displaced by the submerged object. So, if the volume of an object decreased without an apparent decrease in its mass, then the buoyant force will decrease and the object will sink further (until its weight equals or is less than the buoyant force)
How are volume and buoyancy related?
All enantiomers have the same physical properties with the exception of the direction of polarization for plane-polarized light (this would not greatly affect whether or not they are advantageous for bacteria) The reason one is sometimes used while the other is not is that most enzymes are stereospecific
How do the physical properties of D- and L- enantiomers differ?
In series: 1/Ceq = 1/C1 + 1/C2 ..... In parallel: Ceq = C1 + C2 .....
How do you find the equivalent capacitance of capacitors in series? in parallel?
In series: Req = R1 + R2 ..... In parallel: 1/Req = 1/R1 + 1/R2 .....
How do you find the equivalent resistance of resistors in series? in parallel?
F (horizontal) = F cosθ F (vertical) = F sinθ
How do you find the horizontal versus vertical component of a force that is acting on an object at an angle?
E = V/d E is the electric field (V/m) V is the potential difference across the electrodes (V) d is the distance between the electrodes (m) Because 1 V = 1 J/C, 1 V/m = 1 J/C*m = 1 N/C
How do you find the magnitude of the electric field between two electrodes in N/C?
T = 1/f T is the period (s) f is the frequency (Hz) So a wave with the shortest period will have a high frequency and short wavelength
How do you find the period of a wave?
W = Fd cos(theta), where theta is the angle between the force vector and the displacement vector. Since the swimmer swims horizontally and gravity acts vertically, theta = 90. Because cos(90)=0, the world done by gravity not the swimmer is zero.
How do you find the work done by gravity on a swimmer swimming laps in a pool?
A multi-protic acid will have multiple pKa values and multiple weak acid states. Because of this it can act as a buffer at any of these pH ranges which correspond with its pKa's. (Ex: a triprotic acid can act as a buffer across 3 different pH ranges)
How do you know at what pH range a multi-protic acid can act as a buffer?
Atomic radius decreases as you go to the right and up (so the atoms with the largest atomic radius are in the bottom left corner). This is because as you move from left to right across a period, effective nuclear charge increases, meaning the atom will draw the outermost electrons closer in.
How do you know atomic radius from the periodic table?
Southern blot uses restriction digest to differentiate between mutant and wild-type alleles. In order for this to be useful, the mutation should either create or eliminate a restriction site, which are palindromes 4 to 6 base pairs long (5' to 3' sequence is identical and antiparallel to 5' to 3' sequence of complementary strand).
How does a Southern blot identify mutations?
A charged particle accelerates in an electric field. The electron's velocity will increase as it moves through the electric field (towards the positive terminal)
How does an electron's speed change as it moves through an electric field?
Dichloromethane (methylene chloride) acts as an organic solvent, so neutral (non-charged) molecules are soluble in it while polar molecules are not. Additionally, DCM is immiscible with water so it can be used to separate neutral and charged molecules because the charged molecules would dissolve in the aqueous (water) layer.
How does dichloromethane (CH2Cl2) act as a solvent?
An SN2 reaction is one in which the nucleophile attacks the substrate carbon and kicks off the leaving group simultaneously. This is a backside attack, and therefore atoms being in the equatorial position makes SN2 very difficult or impossible. For an SN2 reaction to the possible the leaving group atom should be in the axial position. This isn't that big of a deal because glucose interconverts between its chain form and its 2 ring forms (each atom will be equatorial in one form and axial in the other).
How does the position of an atom attached to a glucose ring affect its ability to engage in an SN2 reaction?
At 1 atm one mole of gas is 22.4 L. According to Boyle's Law, pressure and volume are inversely proportional, so if pressure is doubled then the volume of the same number of moles of gas will occupy half as many liters. (ie. 22.4 L at 1 atm would be 11.2 L at 2 atm)
How does the volume of a gas change with pressure?
Catalytic efficiency is measured by k.cat/Km. This means that a catalytically efficient enzyme-substrate combination will have a high k.cat and a low Km
How is catalytic efficiency measured?
Adenine (A) contains 1 donor and 1 acceptor Thymine (T) contains 1 donor and 1 acceptor Cytosine (C) contains 1 donor and 2 acceptors Guanine (G) contains 2 donors and 1 acceptor
How many H-bond donors/acceptors exist on each of the 4 DNA bases in a Watson-Crick base pair?
2 molecules of NADH and one molecule of FADH2 are generated during the conversion of alpha-ketoglutarate to oxaloacetate in the citric acid cycle
How many/what reduced electron carriers are generated during the conversion of alpha-ketoglutarate to oxaloacetate during the CAC?
Glycolysis produces 2 ATP per molecule of glucose
How much ATP is directly produced from glycolysis?
Ksp = [Fe 3+][OH-]^3 = (x)(3x)^3 Here, x is the concentration of Fe 3+ and 3x is the concentration of OH- 2.64 e-39 = (x)(3x)^3 = 27x^4 x ~ 10^-10
How would you find the concentration of Fe^3+ in a saturated solution of Fe(OH)3 with a Ksp = 2.64 e-39 ?
H is a nonmetal (exception to the trend of nonmetals being on the left and metals being on the right of the periodic table)
Hydrogen is a (metal/transition metal/nonmetal)
For a spontaneous reaction, Keq > 1
If a reaction is spontaneous, what must be true of its K value?
This indicates that these are growing, developing long bones (not yet adult bones) because long bones grow via endochondral ossification, which requires cartilaginous growth plates at the end of long bones
If an X-ray shows cartilaginous areas in the long bones of an individual, what does this indicate?
Absolute poverty will decline, but relative poverty will remain constant
If everyone in a population's income increases and income distribution remains constant, absolute poverty will _________ and relative poverty will _________
towards
If the wavelength measured from an object (observed wavelength) is less than the wavelength of light emitted from the stationary detector (actual wavelength), then the object is moving _____________ the detector
homologous pairs of chromosomes are separated, each still consisting of two sister chromatids joined to each other at the centromere
In meiosis I, _________________ are separated into the two daughter cells
electron affinity (nonmetals like O or S)
In order to act as an electron acceptor, and element should have a high ________________
liver
In order to regulate blood glucose levels, glycogen is made, stored, and broken down in the __________
In myopia (nearsightedness) the focal length is too short (light converges in front of the retina). In hyperopia (farsightedness), the focal length is too long (light converges behind the retina).
In people with myopia, the focal length of the lens of the eye is too _______. In hyperopia, the focal length is too _______.
succinate to fumarate to malate to oxaloacetate
In the citric acid cycle, what is the intermediate compound between succinate and malate? what comes after malate?
alpha(1-4) linkage linearly and alpha(1-6) linkage at branch points
In the liver, glycogen is formed by glycosidic bonds between glucose molecules through _________ linkage linearly and __________ linkage at branch points
Glucose-6-phosphate dehydrogenase
In the pentose phosphate pathway, what enzyme catalyzes the production of 6-phosphogluconolactone from glucose 6-phosphate?
increase, increase Because the capacitor is connected to a voltage source V is constant, and the equation C = Q/V tells us that the increased capacitance must mean the stored charge increases too
Inserting a dielectric in between the plates of a capacitor that is connected to a voltage source will __________ capacitance and ________ the charge stored
Molecules with a C-OH group are more polar than those with a C=O group
Is C=O or C-OH a more polar group?
low
Light travels fastest in mediums with (low/high) indexes of refraction
pyruvate dehydrogenase
Lipoic acid is a cofactor for ____________, the enzyme that catalyzes the conversion of pyruvate to acetyl-CoA
H2O < NH3 < CH4 < CO2 This is because CO2 has an sp central atom (180 degree bond angle), CH4 has no non-bonding electrons, NH3 has one pair of non-bonding electrons, and H2O has two pairs.
List the following in order of increasing bond angle: CH4, H2O, CO2, NH3
skeletal and cardiac muscles contain striated muscle fibers (smooth muscles do not)
Muscles with striated fibers are the primary muscle type in ________________
connective tissue cells
Osteoclasts are __________ cells
epithelial cells
Ovarian cells are ___________ cells
Pyruvate kinase converts ADP to ATP; can be used to couple with a reaction that uses ATP so that ADP levels are kept low
Pyruvate kinase catalyzes the conversion of phosphoenolpyruvate to pyruvate and (uses/forms) ATP
Cooperative process (meaning the binding of the first molecule of B to A affects the binding affinity of the second B molecule to A), sigmoidal curve
Th unfolding of proteins is a _________ process and therefore would have a __________ curve (for the dependence of the fraction of folded protein upon denaturant concentration)
pumps protons from the mitochondrial matrix into the mitochondrial inter membrane space
The electron transport chain uses the free energy from redox reaction to pump __________ from the ________ to the ___________, thereby generating an electrochemical gradient across the inner mitochondrial membrane
This is indicative of starvation. It can also be induced by hormone changes such as low leptin levels.
The following physiological changes indicate _________: elevated plasma cortisol, inability to effectively undergo thermogenesis, decreased locomotor activity, unrestrained appetite, and resistance to insulin
weak base
The leaving group in an SN2 reaction must be a __________
peptidoglycan
The primary component of the bacterial cell wall is ___________
False Capacitors store energy in the electric field between their plates, but batteries also store energy as they are the source of energy for the circuit
True/false: Capacitors are the only circuit element that stores energy
False Though both cell types have ribosomes, prokaryotic and eukaryotic ribosomes are different enough that several types of antibodies are able to preferentially target prokaryotic ribosomes over eukaryotic ribosomes
True/false: Human and bacterial cells are alike in the chemical composition of their ribosomes
True
True/false: Human and bacterial cells are both able to produce ATP via ATP synthase
False Peptide hormones are hydrophilic and soluble in blood. Hormones that must bind transport proteins are steroid proteins, which are lipophilic
True/false: Peptide hormones require transport proteins to remain soluble in the bloodstream
True, because an ion is much more massive than an electron so it will not be able to respond as quickly due to inertia
True/false: Positive ions in a sea of mobile electrons can be considered to be fixed during the electrons' oscillations (movement back and forth to reach equilibrium)
False All of those are true except amino acids, which are not found in sphingolipid head groups
True/false: Sphingolipids can have many different head groups including phosphocholine, phosphoethanolamine, monosaccharides (cerebrosides), oligosaccharides (gangliosides), or amino acids
False The activation of the G proteins promotes the dissociation of bound GDP and its exchange for GTP on the alpha subunit. This is what leads to the activities of adenylate cycle and protein kinase A, and the level of cAMP being increased.
True/false: The activation of a G protein promotes the binding of GDP to the alpha subunit which increases adenylate cyclase activity, protein kinase A activity, and cAMP generation
False The transcript would be found in the cytoplasm and where ribosomes are located, not where the protein itself is functioning, so this would NOT be an effective way to determine localization
True/false: Using a fluorescent probe that hybridizes to the protein's transcript can be an effective way to determine localization of a protein in a cellthe
False In order to be excreted in the urine, a compound must be water-soluble. Water-insoluble compounds are either stored in the body, converted to water-soluble products, or eliminated in the feces. These are transported from the blood into the renal tubule via the glomerulus (only free salt ions can enter the nephron in other places for excretion)
True/false: Water insoluble compounds are excreted in urine
red litmus paper will turn blue when dipped in a basic solution
Used as an indicator, red litmus paper will turn _______ when dipped into a ________ solution
The *hypothalamus* exerts control over the pituitary hormones involved in menstruation by secreting hormone-releasing factors into the pituitary portal circulation. The gonadotropic hormones FSH and LH are produced by the *pituitary* and the ovarian hormones estrogen and progesterone, produced by the *ovaries*, all have a role in regulating the human menstrual cycle.
What 3 organs are involved in the hormones that regulate the events in the human menstrual cycle?
D is aspartate (E is glutamate)
What amino acid is "D"?
W is tryptophan (hydrophobic, aromatic amino acid)
What amino acid is W?
Dideoxynucleotides are chain-elongating inhibitors of DNA polymerase used in the Sanger (chain-termination) method for DNA sequencing. Without these, the DNA polymerase would replicate the entire template strand of DNA and thus produce complete copies, all of the same length. This would lead to only one band being shown on a gel electrophoresis.
What are dideoxynucleotides?
A subtype of diastereomers that differ in absolute configuration at exactly one chiral carbon
What are epimers?
Melanocyte cells are neural crest-derived cells that produce melanin that is responsible for the pigment of the epidermis and the iris (colored part) of the eye
What are melanocyte cells?
Alkane: 0-3 ppm Alkene: 4.5-6 ppm
What are the NMR peaks for protons attached to alkane and alkene carbons?
The acidic amino acids are aspartic acid and glutamic acid, which are negatively charged at pH = 7.4
What are the acidic amino acids?
The basic amino acids consist of arginine and lysine, which are positively charged at pH = 7.4
What are the basic amino acids?
The vasa recta
What are the capillaries that supply nutrients to the nephron known as?
PCR reactions require primers that are complementary to the DNA that flanks the region of interest. The primer must have high GC content to provide stability.
What are the characteristics of a PCR primer?
PE = m g h KE = 1/2 m v^2 PE and KE and potential and kinetic energy (J) m is mass (kg) g is acceleration due to gravity (m/s^2) h is the height above the ground (m) v is the velocity of the object (m/s)
What are the equations for kinetic and potential energy?
Affective: the emotional component of attitude (ex: disliking something) Behavioral: the component of attitude which results in a tendency to behave in a certain manner (ex: wanting to act to prevent something which the person does not like) Cognitive: the component that comprises thoughts and beliefs (ex: stereotypes)
What are the three components of attitude?
Cardiac output (stroke volume x heart rate) and the resistance to blood flow
What are the two factors that normally determine blood pressure?
Tosylate ions are generally used to make an alcohol into a better electrophile (tosylates are very good electrophiles and prefer to react with alcohols over carboxylic acids)
What are tosylate ions generally used for?
hypothalamus
What brain structure controls appetite?
A colored solution probably contains ions with unfilled / partially filled d orbitals. This is because the electrons in the lower energy d orbitals absorb visible light to move to the higher energy d orbitals.
What can color tell you about the electron configuration of ions in a solution?
Typical cells have organelles which have membranes and membrane proteins, meaning the plasma membrane is only a fraction of the cell's membranes. Erythrocytes are the one type of cell that lacks organelles, therefore using these cells would allow for studying only plasma membrane proteins.
What cells would a researcher wanting to study plasma membrane proteins choose to use for their study?
Any element is defined by its number of protons. If the number of protons of an atom changes then it is a new element. The atomic mass number can change though by changing the number of neutrons in the nucleus, creating isotopes
What defines an elements?
SDS-PAGE: separates proteins based on their mass Isoelectric focusing: separates proteins based on their isoelectric point (the pH at which the net charge of the protein is zero) Ion-exchange chromatography: separates proteins based on their net charge Affinity chromatography: separates proteins based on their interactions with specific ligands
What do the following separate proteins based on: SDS-PAGE, isoelectric focusing, ion-exchange chromatography, and affinity chromatography?
Isoelectric focusing is a mechanism of visualizing proteins and separating them based on isoelectric point. To do this, a stable pH gradient must be established in the gel.
What does isoelectric focusing entail?
Native gel electrophoresis will show the comparative size and shape of molecules based mostly on secondary structure, and more compact molecules will elute further
What does native gel electrophoresis show?
The focal length of a mirror depends only on the radius of curvature of the mirror f = r/2
What does the focal length of a mirror depend on?
The reaction order is the number of reactant molecules involved. For example, a reaction that involves second-order kinetics will only involve two reactant molecules. So, it could be a collision between A and B or A and A, but it could NOT be a collision between 2 A's and a B
What does the kinetics order of a specific step of a reaction mechanism tell you about that step?
strontium
What element is Sr?
mesoderm
What embryonic layer does dermal tissue derive from?
ectoderm
What embryonic layer does nervous tissue derive from?
Glycogen phosphorylase
What enzyme catalyzes the rate-limiting step in glycogen breakdown (glycogenolysis)?
Carbonate reacts with water to produce OH-, forming a basic solution If HCl is then added to the solution, carbonate (CO3 ^2-) will react with it to form CO2 (g)
What happens to carbonate molecules in aqueous solution? What happens if HCl is added?
luteinizing hormone (LH)
What hormone is directly involved in triggering ovulation?
6.02 x 10^23 ions/mol (or molecules/mol)
What is Avogadro's number?
A Hill coefficient is a measure of cooperativity. n > 1 = positive cooperativity (binding of one substrate increases affinity for binding of the next substrate) n = 1 = no cooperativity n < 1 = negative cooperatively (binding of one ligand makes it more difficult for subsequent ligands to bind) If an enzyme's Hill coefficient is barely above or below 1 (ex: 1.05) assume it does not exhibit cooperativity
What is a Hill coefficient?
A bomb calorimeter is a constant-volume device used to measure the energy released during a combustion reaction; it does this by being adiabatic (exchanges no heat with the environment); only efficient when the reactants are starting from their standard state (ie. not activated)
What is a bomb calorimeter?
one of a network of tubes running through compact bone that contains blood vessels and nerves
What is a haversian canal?
A molecule made up of multiple, identical monomer units (on any PAGE would come up as a single band)
What is a homopolymers (ex: homodimer)?
A longitudinal wave is a wave in which the oscillation of the material is parallel to the direction of propagation; looks like a coil around an axis on a diagram; sound is a classic example
What is a longitudinal wave?
A mediating variable is one that impacts and helps explain the relationship between two other variables (ex: social capital is hypothesized to mediate the relationship between family structure and function)
What is a mediating variable?
protein domains (ie. functional part of proteins) required for proteins that are directed toward secretory pathways; tags them for transport through the cell membrane and out of the cell
What is a signal sequence domain?
A ternary complex is formed when two substrates bind to an enzyme at the same time. This is an intermediate in a multi-substrate enzyme catalyzed reaction.
What is a ternary complex?
A transverse wave is a wave that propagates in a direction perpendicular to the direction of oscillation; diagram looks like typical wave; example would be waves created by wiggling a rope or the ripples in water
What is a transverse wave?
Asparagine (Asn)
What is amino acid N?
Glutamine (Gln)
What is amino acid Q?
An enol is a molecule that contains an alcohol adjacent to a double bond. An enolate is the anion formed when the alcohol in an enol undergoes deprotonation.
What is an enolate?
Transformation results from the integration of foreign genetic material into the prokaryote's genome. This genetic material usually comes from other bacteria that have been lysed.
What is bacterial transformation?
Conjugation is the bacterial form of mating. One bacterial cell produces a *sex pilus* which is used to transfer DNA to another bacterium. The formation of the pilus requires special genes present on a plasma, separate from the bacterium's own DNA. This plasma is referred to as the *fertility (F) factor* which is replicated and donated to the accepting cell through the pilus.
What is conjugation?
Denaturing gel electrophoresis separates molecules based on molecular mass (size); If you are using this to distinguish between DNA strands and they all elute the same distance, then they all have the same number of nucleotides (even though their secondary structures may differ)
What is denaturing gel electrophoresis?
Diamagnetism is a condition that arises when a substance has no unpaired electrons and is slightly repelled by a magnetic field
What is diamagnetism?
Ligand-gated channels open to allow the flow of ions after the binding of a specific binding substance (ligand), usually a hormone or neurotransmitter Ex: Influx of Na+ across the motor end plate in order to depolarize muscle fiber membranes occurs once the ion channels bind to the ligand acetylcholine
What is different about ligand-gated ion channels?
Hindsight bias is the tendency of people to overestimate their ability to have predicted an outcome that could not possibly have been predicted.
What is hindsight bias?
This indicates cooperatively and therefore that the enzyme must have more than one subunit
What is indicated by a graph on an enzyme's activity versus its substrate concentration that is sigmoidal?
Mass defect is the difference in mass between a nucleus and the protons and neutrons that form it
What is mass defect?
Tm is the temperature at which 50% of the molecules are denatured or the fraction unfolded is 0.5
What is melting temperature (Tm)?
Myoglobin is the substance that holds oxygen in muscles and organs
What is myoglobin?
Paramagnetism is a condition that arises when a substance has unpaired electrons and is slightly attracted to a magnetic field
What is paramagnetism?
Power is the rate at which energy is transferred or transformed. It is measured as the ratio of work (energy expenditure) to time (P = W/t). In a circuit, the power of a resistor can be found from P = IV = I^2*R = V^2/R The units of power in either case are J/s
What is power?
Random error is caused by unpredictable changes in the experiment and does not specifically push the results in one particular direction (ie. it does NOT affect the entire experiment in the same way) An example would be using a different column for each sample when using liquid chromatography because each column is prepared separately and one could potentially be defective (while using one column for all samples could lead to systematic error if the one column was defective)
What is random error?
Amplifies sequences corresponding to RNA. Reverse transcriptase is used to convert RNA into complementary DNA, which can then be amplified by the usual polymerase chain reaction
What is reverse transcription PCR?
Saponification is the process by which fats (esters of fatty acids and glycerol) are hydrolyzed under basic conditions (sodium or potassium hydroxide) to form an alcohol (typically glycerol) and a carboxylic salt (known as a soap) basically breaking the tails off of the fatty acid so all that's left is the glycerol backbone
What is saponification?
Self-selection bias is a bias that is introduced into a research project when participants choose whether or not to participate in the project, and the group that chooses to participate is not equivalent (in terms of the research criteria) to the group that opts out. This could also apply to a study in which participants can self-identify which group they are classified into. For example, in a study on the health of household diets people who live in households of unhealthy eaters may choose to not identify as the primary food purchasers of their household, even though in reality one member of each household must be the primary purchaser.
What is self-selection bias?
Serotonin is a neurotransmitter derived from the amino acid tryptophan which is associated with mood (increased serotonin increases happiness and reduces anxiety), sleep, eating, and dreaming
What is serotonin?
Systematic errors consistently bias results from an experiment in a particular manner (ie. in one direction); associated with faulty equipment or a flawed experimental design (ex: instrument being calibrated wrong)
What is systematic error?
pH = pKa + log([A-]/[HA])
What is the Kenderson-Hasselbach equation (finding pH from weak acid and conjugate base concentrations)?
Carboxylic acid group of amino acids: 2 -NH3+ group of amino acids: 9 R group of Histidine: 6 R group of aspartic/glutamic acid: 4
What is the approximate pKa (pH at which it deprotonates) of the following: Carboxylic acid group of amino acids -NH3+ group of amino acids R group of Histidine R group of aspartic/glutamic acid (very similar)
1 amino acid ~ 110 Da
What is the average molecular weight of an amino acid?
According to the common ion effect, when an ion is present in solution, it becomes harder to dissolve more of that ion in solution. For example, barium sulfate (BaSO4) would be less soluble or insoluble if dissolved in a solution of iron(III) sulfate [Fe2(SO4)3] because there would already be a concentration of SO4^2- in the solution.
What is the common ion effect?
A reducing sugar must have a hemiacetal end. So, all monosaccharides are reducing sugars and disaccharides that have an anomeric carbon with an -OH (ie. the glycosidic bond is not between a C1 and another C1) are reducing sugars.
What is the criteria for being a reducing sugar?
Alpha and beta monosaccharides are anomers, having opposite absolute configurations at their hemiacetal (anomeric) carbons. This configuration will determine whether the -OH group is axial or equatorial in a cyclic monosaccharide Beta would have an equatorial -OH group on the C1 (pointing up) Alpha would have an axial -OH on C1 (pointing down)
What is the difference between alpha-D-fructose and beta-D-fructose?
Atomic iron: [Ar]4s^2 3d^6 Iron (III) ion: [Ar]3d^5 This is because the first two electrons are always stripped away from the outermost orbital (the s orbital, and after that the electrons come from the d orbital, the next outermost orbital)
What is the electronic configuration of atomic iron and the iron(III) ion?
f' = f ( [V +/- V.detector] / [V +/- V.source] ) f' is the observed frequency detected (Hz) f is the actual frequency emitted by the device (Hz) V is the velocity of the sound wave in the medium in which it is traveling (m/s) V.detector is the velocity at which the detector is moving, which is typically 0 (m/s) V.source is the velocity at which the source is moving (it will be added if the source is moving away from the detector and it will be subtracted if the source is moving towards the detector, this is because frequency decreases when the source is moving away and increases when the source is moving towards)
What is the equation for the Doppler effect?
E = 1/2 x C x V^2 Where C is the capacitance and C is the voltage across the capacitor
What is the equation for the energy stores by a capacitor?
F = Eq F is the electric force acting on the charged particle E is the electric field that the particle is in q is the charge of the particle
What is the equation for the force acting on a charged particle in an electric field?
T = r F sinθ T is torque (N*m) r is the radius (ie. distance between the pivot and the acting point) (m) F is the applied force or weight (N) sinθ is the angle at which the force is applied
What is the equation for torque?
Bile is produced by the liver and facilitates fat absorption in the small intestine by breaking large fat droplets into smaller ones
What is the function of bile?
The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the circulatory system and the immune system. It is made up of a large network of lymphatic vessels, lymphatic or lymphoid organs, and lymphoid tissues. The vessels carry a clear fluid called lymph (which carries infection-fighting white blood cells) towards the heart.
What is the lymphatic system>?
The adrenal medulla controls hormones that are part of the fight or flight response; it secretes epinephrine (adrenaline) and norepinephrine (noradrenaline)
What is the main purpose of the adrenal medulla?
-CH2SH (cysteine) has a higher priority than -COOH
What is the only amino acid side chain that will have a higher priority than the carboxylic acid group when determining R/S configuration?
-2
What is the oxidation state (charge) of sulfate (SO4)?
Smooth muscle
What is the primary muscle type of the uterus, blood vessels, and small intestine?
Use of a reducing agent in gel electrophoresis will disrupt disulfide bonds
What is the purpose of using a reducing agent in gel electrophoresis?
Harmonics and frequency are directly proportional First harmonic = f1 Second harmonic = 2 x f1 Third harmonic = 3 x f1
What is the relationship between harmonics and frequency of a wave?
A1v1 = A2v2 Because the relationship is based on cross-sectional area, the the radius and linear velocity have an inverse squared relationship (ie. if the radius is halved, then the velocity will increase by a factor of 4)
What is the relationship between the radius of a tube and linear flow in a continuous tube such as an artery (ie. the continuity equation)?
The separation of the two liquids takes place in the fractionating column as the two liquids vaporize and condense. The more time the liquids spend in the column, the more theoretical plates there will be and the more times the liquids with vaporize and condense. Therefore, lengthening the fractionating column will enhance the degree of separation between the liquids.
What is the relevance of the length of the fractionating column in fractional distillation?
HO-CH2-CH-OH-CH2-OH
What is the structure of glycerol?
Transduction is the transfer of genetic material from one bacterium to another via a bacteriophage vector (virus that carries the genetic material from one bacterium it infects to the next)
What is transduction?
Vasoconstriction; As blood is lost from circulation, reduction in vessel size helps maintain the necessary pressure to keep the blood circulating to all body tissues; Typically, vasoconstriction, the narrowing of a blood vessel, restricts blood flow to an organ and can increase blood pressure
What maintains blood pressure during a hemorrhage?
Compounds with the greatest difference in electronegativities between their metal and nonmetal have the most ionic character
What makes an ionic compound have greater ionic character?
Gluconeogenesis
What metabolic pathway is used to increase glucose levels from non-carbohydrate sources including fatty acids and glucogenic amino acids?
The p-value must be less than 0.05 in order for data to be considered statistically significant
What must a p-value be in order for findings to be considered significant?
Guanosine
What nucleoside has the largest molecular weight?
Hydrochloric acid is produced by the parietal cells of the stomach
What organ produces hydrochloric acid?
Glucagon is secreted by the alpha cells of the pancreas
What organ secretes glucagon?
Succinyl-CoA synthetase plays a key role in the citric acid cycle. It catalyzes the conversion of succinyl-CoA and GDP to succinate and GTP
What reaction does succinyl-CoA synthetase catalyze?
An action potential that results in muscle contraction will cause t-tubule depolarization, followed by the sarcoplasmic reticulum releasing Ca 2+ into the systole where it binds to the troponin complex, thereby allowing tropomyosin to expose the myosin-binding sites on actin
What role does Ca 2+ play in inducing muscle contraction?
Metals are to the left, Non metals are to the right (Halogens are the last group to the right)
What sides of the periodic table are metals and non metals?
Muscle cells, because the number of mitochondria in a cell is dependent on the energy needs of the tissue
What type of autosomal cells have the highest content of mitochondria?
Uncompetitive inhibitors bind to the ES complex lower the value of both Km and Vmax, and do not alter the slope of the Lineweaver-Burk plot (ie. the Km/Vmax ratio) Uncompetitive inhibitors are most effective when both substrate and inhibitor concentrations are high
What type of inhibitor does NOT alter the Km/Vmax ratio of an enzyme?
This indicates that the inhibitor is a noncompetitive inhibitor and binds the enzyme and enzyme-substrate complex with the same affinity, Vmax is decreased but Km does not change
What type of inhibitor is shown on a Lineweaver-Burk plot in which the lines of E + S and E + S + I meet at the x-intercept but have different y-intercepts?
Noncompetitive, uncompetitive, and mixed (competitive inhibitors are the only inhibitors that do not affect the y-intercept on a Lineweaver-Burk plot)
What type of inhibitors alter Vmax?
Silica plates (the stationary phase) are very polar, so polar molecules will "stick" and have a lower Rf, while non polar molecules will have higher Rfs.
What type of molecule will have the highest Rf when doing thin-layer chromatography on silica plates?
Negative pressure pumping action The lungs stay in contact with the thoracic wall as it enlarges due to contraction of the diaphragm, and a pressure that is lower than atmospheric pressure (negative pressure) is generated that pulls air into the lungs. The opposite would be positive pressure pumping, which would occur when things like a bag valve mask force air into the lungs to expand them
What type of pressure pumping is used to inflate the lungs?
Sound waves are longitudinal waves
What type of waves are sound waves?
Anionic proteins (negatively charged) will bind to anion exchange columns. A larger negative charge means it will bind more tightly and therefore a higher concentration of NaCl would be required for elution.
What types of molecules will bind to an anion-exchange column? What will indicate how much NaCl will be needed for the elution of the molecule?
620-750 nm Oxygenated blood reflects bright red light, and red is the wavelength on the visible spectrum which the longest wavelength and lowest frequency
What wavelength would oxygenated blood show the least absorbance at?
Keq = [C3]^r [D] / [A2]^p [B]^q 1 D = r C3, so... (1/r)[C3] = [D]
What would be the equation to find the equilibrium constant (Keq) of the following reaction: p A2 + q B <--> r C3 + D What is the concentration of D with respect to C3?
If you had X moles of A2B3 to begin with, then you would have 2X moles of A and 3X moles of B. To solve in terms of solubility, the expression would be Ksp = (2 x)^2 (3 x)^3 = (4 x^2) (27 x^3) = 108 x^5
What would be the expression for finding Ksp of A2B3
decreases When insulin levels fall, glucose uptake decreases and the utilization of fatty acids as fuel and the conversion of glycogen into glucose increases in tissues (triggered by glucagon release in response to low insulin levels)
When insulin levels fall, the utilization of glucose as fuel ____________
The image will be real and inverted
When the object is at a distance outside the focal length, what type of image is formed by a *converging lens*?
These children are in the preoperational stage, in which they still lack the concept of conservation (principle that quantity remains the same despite changes in shape)
Which of Piaget's stages of cognitive development are children aged 2-7 in?
Acetyl-CoA is the only molecule listed here that is not used as a starting material in gluconeogenesis. Acetyl-CoA actually inhibits the pyruvate dehydrogenase complex which stimulates gluconeogenesis by acting pyruvate carboxylase (which converts pyruvate to oxaloacetate) Lactate and glycerol, as well as the amino acids alanine and glutamine, are common precursors in gluconeogenesis. Citric acid cycle intermediates such as oxaloacetate and alpha-keotglutarate can also be used.
Which of the following can be used as precursors for gluconeogenesis: lactate, glycerol, alanine, glutamine, acetyl-CoA, oxaloacetate, and alpha-ketoglutarate
In an SDS-PAGE run under non-reducing conditions, the smallest protein will have the greatest electrophoretic mobility. Here, proteins 1, 3, and 4 will run as monomers but 2 will run as a dimer because the disulfide bonds are not reduced. Thus there masses would be 32, 38, 25, and 38. Therefore 3 is the smallest protein and will have the highest electrophoretic mobility.
Which of the following has the highest electrophoretic mobility in SDS-PAGE under non-reducing conditions? Protein 1: 32 kDa monomer Protein 2: Disulfide-linked homodimer comprised of 19 kDa monomers Protein 3: Homotrimer comprised of 25 kDa monomers Protein 4: Homodimer comprised of 38 kDa monomers
The two plates of a capacitor collect charges of opposite sign. As more charge arrives it is harder and harder to fill the plates until finally an equilibrium occurs. Thus, successive charges brought to the plates are repelled by charges accumulated earlier.
Why can't a capacitor accumulate charge indefinitely?
A resistance to or lack of insulin would result in decreased availability of glucose for cells. The cells would switch to beta-oxidation of fatty acids for energy, producing acetyl-CoA which will undergo ketogenesis to produce ketone bodies such as acetone.
Why does decreased insulin result in sweet, acetone smelling breath?
This occurs because the light is absorbed and re-emitted by the atomic structure of the optically dense medium
Why does light travel more slowly through an optically dense medium than through a vacuum?
Antibodies may be denatured (destroyed) in the harsh (acidic) environment of the stomach
Why might antibodies be ineffective against bacterial infections in the stomach?
No; An aromatic ring must have 4n + 2 pi electrons (6, 10, 14, etc.)
Would an 8-membered carbon ring with alternating double and single bonds (so 4 double bonds and 8 pi electrons) be considered aromatic?
Zwitterions are neutral molecules that are polar due to having a separation of unlike charges. Molecules that contain strong electrons-withdrawing or electron-donating substituents, which is true of most zwitterions, tend to be highly polar and will have correspondingly high dipole moments. Example would be glycine existing as a dipolar ion in aqueous solution
Zwitterions tend to have _______ dipole moments
Southern
_________ blotting cannot be used to analyze gene expression
Leukocytes
___________ are white blood cells of the immune system, and one thing they do is gravitate towards areas of inflammation (caused by a potential pathogen)
vasodilation
____________ increases blood flow to the muscles during exercise and the skin during blushing
Glucose-6-phosphatase (hydrolyzes glucose-6 phosphate, releasing a phosphate group and a free glucose molecule)
________________ catalyzes the final step of both gluconeogenesis and glycogenolysis
