WGU Biochemistry OA RATED A+ (latest 2023)

WGU Biochemistry OA 2023 Bohr Effect chart (low pH) - correct answer C- High CO2 H- High H+ A- Acidic R-Release of O2(rt. Shift) T- tense state (in tissues) Primary structure - correct answer Sequence of amino acids that make up a protein Secondary Structure - correct answer Sequence of amino acids fold. Tertiary Structure - correct answer -more folding in a 3D shape. -R groups (side chains) Quaternary Structure - correct answer Protein has more than 1 polypeptide chain. Chemical reaction - correct answer -absorb and release energy -activation energy -energy is released (heat & light) when bonds are broken. Exothermic reaction - correct answer Exo=to release Thermo=heat -chemical reaction that releases more energy than it absorbs (as heat & light) Example of exothermic reaction - correct answer Cellular respiration- breaks down glucose to make cellular energy Endothermic reaction - correct answer Endo=absorb Thermos=heat -absorbs more energy than it releases Example of endothermic reaction - correct answer Photosynthesis- takes in light to break down to create glucose Catalyst - correct answer Substance that will decrease the activation energy needed to start a chemical reaction Enzymes - correct answer -catalysts used by cells -increase the rate of chemical reaction -specific to substrates Enzyme structure - correct answer -they are proteins -twist, fold, bend to final shape -shape attracts specific molecules Substrate - correct answer Molecules that bind to the enzyme Active site - correct answer -location on enzyme where substrate binds Function of DNA polymerase in process of PCR. - correct answer -increase expression -2 genes -SIRT1 & SIRT2 Function of a molecule - correct answer Structural component of the lipid bilayer How would lipid production in a cell change in order to maintain fluidity of its cell membrane as it adapts to lower temperatures? - correct answer Produce lipids with shorter fatty acid chains Function of cholesterol - correct answer Maintains membrane fluidity Lipid (fat) soluble vitamins - correct answer A, D, E, K What stimulates beta-oxidation of fatty acids? - correct answer An increase in NAD+ concentration in the mitochondrial matrix What occurs in an otherwise healthy person whose diet has very few carbs and high levels of fats? - correct answer Acetone is produced in the blood Amino acids - correct answer -Non-polar (hydrophobic) -Polar charged -Polar uncharged Which type of mammalian DNA damage repair requires the presence of the chromosome that is homologous to the damaged chromosome? - correct answer Recombination Xeroxerma Pigmentosum (XP) - correct answer A recessive genetic disease that occurs when one or more of the genes that perform nucleotide excision repair are nonfunctional Why do XP patients have a much higher incidence of skin cancer than the general population? - correct answer The mutation of all other genes is higher due to failure to repair. Assuming 100% reaction efficiency, how many DNA copies are created after the completion of 4 complete PCR cycles? - correct answer 16 What is the function of DNA polymerase in the process of PCR? - correct answer It recognizes the primers and uses the available dNTPs to replicate the template DNA sequence. What difference in the regions of the SIRT1 & SIRT2 genes in people addicted to cocaine increases their expression? - correct answer The nucleosomes become more widely spaced. What occurs during the process of alternative splicing of RNA? - correct answer Alternate combinations of Exons within the same gene are linked together. Polypeptides - correct answer -functional proteins -made of folded up polymers Elements - correct answer Substance that cannot be broken down into another substance by chemical reaction. Ionic bond - correct answer Actions share + & - charge Covalent bond - correct answer When atoms share electrons Hydrogen bond - correct answer Forms when portion of a polar molecule that is partially positive interacts with portion of a polar molecule that is partially negative Van der Waals interactions - correct answer Occur due to random, transient movements of electrons that at any given instant, give molecules regions of + & - charges. Amino acid - correct answer -has amino group (-NH2) -& a carbonyl group (-COOH) -cx. Based on side chains Elevated levels of AST & ALT - correct answer -indicates liver damage (When damaged, their protein contents can spill into blood stream) Which level of protein structure is disrupted through the hydrolysis of peptide bonds? - correct answer Primary Sickle cell disease - correct answer Caused by mutation in the Hgb-beta gene. (Causes cells to become rigid, sticky, misshapen.) Which force is most influential in determining the secondary structure of a protein? - correct answer Hydrogen bonding Hydrophobic effect - correct answer Tendency of non polar substances to aggregate in an aqueous solution & exclude water molecules. Hydrophobic interaction - correct answer Mutation of gene for protein that leads to substitution of no polar amino acid with charged amino acid Dopamine - correct answer -neurotransmitter -variety of functions (including motor control) Parkinson's = decreases dopamine. Sinemet helps by increasing dopamine levels. Lactose breaks down into : - correct answer Glucose and galactose Frameshift mutation - correct answer -insertion or deletion of 1 or 2 nucleotides Missense mutation - correct answer -substitution of one amino acid for another -results in 10 different amino acids or 10 missense mutations Nonsense mutation - correct answer -premature stop codon incorporated into the sequence -leads to a shorter protein Carbohydrates - correct answer -linear -CH2O formula -energy=glucose -structure=cellulose