FREE BACE Chemistry and Biochemistry Flashcards
6 cards from real BACE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 FREE BACE Chemistry and Biochemistry flashcards as text
What is the chemical basis for enzyme catalysis?
Answer: Enzymes lower the activation energy of reactions increasing the reaction rate without being consumed
Enzymes lower the activation energy (Ea) of biochemical reactions by stabilizing the transition state, dramatically increasing the reaction rate without being permanently altered.
What is the difference between an agonist and an antagonist in the context of receptor pharmacology?
Answer: An agonist binds and activates a receptor; an antagonist binds but blocks receptor activation
Agonists bind receptors and trigger their biological response; antagonists bind receptors but block the response, often competing with natural agonists.
What is the Michaelis-Menten constant (Km) a measure of?
Answer: The substrate concentration at which the reaction rate is half of Vmax reflecting the affinity of the enzyme for its substrate
Km is the substrate concentration at which reaction rate = Vmax/2. A low Km indicates high affinity (enzyme is half-saturated at low substrate concentration); a high Km indicates low affinity.
What type of chemical bond holds the two strands of the DNA double helix together?
Answer: Hydrogen bonds between complementary base pairs
The two DNA strands are held together by hydrogen bonds between complementary base pairs (A-T: 2 hydrogen bonds; G-C: 3 hydrogen bonds).
What is the primary structure of a protein?
Answer: The linear sequence of amino acids linked by peptide bonds
Primary structure is the sequence of amino acids in the polypeptide chain, connected by peptide bonds — it is the most fundamental level of protein structure.
What is the function of NADH and FADH2 in cellular respiration?
Answer: They are electron carriers that donate electrons to the mitochondrial electron transport chain driving ATP synthesis
NADH and FADH2 are reduced electron carriers that transfer high-energy electrons to the mitochondrial electron transport chain, driving proton pumping and ATP synthesis.