NS3: BBCF Flashcards
restriction enzymes
Restriction enzymes cut near or at their recognition sequences. However, if the gene is methylated, this cutting cannot occur.
Sex linked traits
- specifically X linked recessive
X-linked recessive conditions affect males more often. This is because females inherit one X chromosome from their mother and one from their father, while males only get their single X chromosome from their mother.
Thus, females have a chance to obtain a dominant X chromosome, such that the recessive mutation won’t manifest. Since males only have one X chromosome, having a single mutated allele will suffice to manifest a recessive mutation.
carrier properties of ETC
mobile and hydrophobic
mobile bc carriers travel inside the inner mitochondrial membrane, passing electrons from one to another and pumping protons across the inner mitochondrial membrane
hydrophobic bc they need to be able to travel inside the hydrophobic interior of the membrane ;; remember, like interacts w like
However, cytochrome c is a highly water-soluble protein, unlike other cytochromes.
where in the body does glucagon act in a high concentration
Glucagon is released by the pancreas as a response to low blood glucose levels. Its main purpose is to increase glycogenolysis to increase blood glucose. The glycogen stored in the liver is broken down to create glucose that is released into the bloodstream; therefore, most of glucagon’s action occurs in the liver.
what is an organic compound
- also, what is an organic acid
An organic compound must contain carbon and hydrogen in its formula. Furthermore, there must be a covalent bond between a carbon and hydrogen atom in the molecular structure.
Organic acids are weak acids, generally having formulas of R-CO2H, with the acidic hydrogen bonded to an oxygen atom.
Viruses
obligate intracellular parasites, thus must hijack host cells to replicate
The genetic material of viruses can be in the form of either single-stranded or double-stranded DNA or RNA
Single-stranded RNA viruses are further subdivided into positive-sense and negative-sense viruses. Positive-sense RNA viruses contain mRNA that can immediately be translated by the cell.
Negative-sense RNA viruses contain RNA that is complementary to mRNA, meaning that mRNA must be synthesized by an enzyme known as RNA replicase that is carried in the virion.
define the following:
- bacteriophage
- retrovirus
Bacteriophages: viruses whose host cells are bacteria → Instead of entering the cell completely, they inject their genetic material into their host through a syringe-like structure known as a tail sheath
– Two distinct life cycles: lytic and lysogenic
Retroviruses: distinct class of single-stranded RNA viruses that use an enzyme known as reverse transcriptase to synthesize DNA from their RNA genome → eg. HIV
post transcriptional modifications
vs post TRANSLATIONAL
Post-transcriptional modifications: occur in mRNA, specifically in nucleus→ addition of the 5’ cap, poly A tail and splicing
Post-translational modifications: occur after protein has been formed from mRNA, can happen in many areas of the cell → groups being added to the protein by covalent bonds or cleavage of protein
Lifecycle of bacteriophages
During the lytic cycle, the bacteriophage essentially works to replicate at full speed, making full use of the host cell’s machinery. Eventually, the host cell is filled with virions to the point that it bursts or lyses, and a tremendous number of new virions spill out into the environment.
Alternately, in the lysogenic cycle, bacteriophages can integrate themselves into the host genome, at which point they are referred to as a prophage or a provirus. In response to environmental signals, the prophage can re-emerge from the host genome and resume a lytic cycle.
define the following:
- transduction
- transformation
- conjugation
Transduction is a form of horizontal gene transfer in bacteria in which bacteriophages (viruses that infect bacteria) transmit genomic material.
Vs. Transformation involves direct uptake of genetic material from the environment and is not mediated by viruses.
Vs. Conjugation is a horizontal gene transfer process in bacteria in which plasmid DNA is transferred from one bacterium to another through a pilus. Viruses are not involved.
reaction rate
+ order of reactions
Reaction rate itself has units of M/s or mol/L∙s. [A] and [B] are concentrations of the reactants in units of M or mol/L. The exponents x and y must be experimentally determined; they do not correspond to the stoichiometric coefficients a and b in the reaction formula.
The order of a reaction is defined by the sum of the exponents (x + y) in the rate law. If the exponents sum to zero, the reaction is zero-order. If the reactants sum to 1, the reaction is first-order. If they sum to 2, it is second-order, and so on.
Note that at low substrate concentrations, the reaction approximates first-order kinetics, as described above. In contrast, at very high substrate concentrations (where the enzyme is nearly or entirely saturated), the reaction approximates zero-order kinetics, since reaction rate ceases to depend on substrate concentration.
are viruses living??
Viruses are unique in that they occupy a gray area between living and non-living. They have been described as non-living. Prions, or pathogenic misfolded proteins, are also non-living biological substances that are pathogens, but they are not considered organisms.
triglycerides
saponificiation
Triglycerides are composed of 1 glycerol molecule and 3 fatty acid molecules. So, if we start with 3000 triglyceride molecules, we would expect to have 9000 molecules of fatty acids and 3000 molecules of glycerol after hydrolysis.
Saponification: carboxylic acids are deprotonated and their conjugate bases form salts, according to the following template: RCOOH + Na+ + OH− → RCOO−Na+ + H2O
– the process can be combined with the base-catalyzed hydrolysis of a triglyceride containing three fatty acid chains
malonyl coA
Malonyl-CoA, an indicator of ongoing fatty acid synthesis, inhibits β-oxidation by preventing the movement of long-chain acyl groups into the mitochondrial matrix, thereby preventing a futile cycle of fatty acid synthesis followed by immediate β-oxidative catabolism of those newly synthesized fatty acids.
can a purine turn into a pyrmidine?
no, not even by methylation or deamination bc purines and pyrimidines differ based on whether they have a 1-ring structure (pyrimidines) or a 2-ring structure (purines), and the loss or addition of a single functional group (as in (de)methylation or (de)amination) is insufficient to convert between these very different structures.
BUT you should know that purines are likely to mutate into other purines
