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CSIR NET Life Sciences Molecules And Their Interaction Relevant To Biology Flashcards
51 question-and-answer cards covering Molecules And Their Interaction Relevant To Biology as it is examined in CSIR NET Life Sciences. 24 of them are printed below, taken from across the deck — no signup, no paywall on the preview.
24 sample cards from the Molecules And Their Interaction Relevant To Biology deck
Sampled from the end of the deck, so these are different cards from the ones shown on the syllabus page.
Define reaction order and give the rate law for a first-order reaction.
Reaction order is the sum of exponents of concentration terms in the rate law. First order: rate = k[A], with units of k in s^-1 and an exponential decay of [A] over time.
What is the net ATP and NADH yield of glycolysis per glucose?
Net 2 ATP (4 produced, 2 consumed), 2 NADH, and 2 pyruvate per glucose molecule.
Name the three irreversible (regulatory) enzymes of glycolysis.
Hexokinase, phosphofructokinase-1 (PFK-1, the key control step), and pyruvate kinase.
Where does oxidative phosphorylation occur and what is its overall function?
It occurs at the inner mitochondrial membrane. Electrons from NADH/FADH2 pass through the electron transport chain, pumping protons to create an electrochemical gradient that ATP synthase uses to make ATP.
State the chemiosmotic theory (Mitchell's hypothesis).
Energy from electron transport is used to pump protons across the inner mitochondrial membrane, creating a proton-motive force (electrochemical gradient) that drives ATP synthesis as protons flow back through ATP synthase.
What is the approximate ATP yield from complete oxidation of one glucose molecule (modern estimate)?
About 30-32 ATP total (glycolysis + pyruvate oxidation + citric acid cycle + oxidative phosphorylation).
What is a coupled reaction in metabolism?
A thermodynamically unfavorable (endergonic) reaction is driven by linking it to a favorable (exergonic) reaction, typically ATP hydrolysis, so the combined deltaG is negative.
What is a group transfer reaction and give a biological example?
A reaction transferring a functional group from one molecule to another; e.g., kinases transfer a phosphoryl group from ATP to a substrate (phosphoryl group transfer).
What are biological energy transducers? Give examples.
Systems that convert one form of energy into another usable form, e.g., ATP synthase (proton gradient -> chemical energy in ATP), chloroplasts (light -> chemical energy), and muscle (chemical -> mechanical energy).
State the Michaelis-Menten equation and define Vmax and Km.
v = (Vmax[S]) / (Km + [S]). Vmax is the maximal rate at saturating substrate; Km is the substrate concentration at half Vmax and reflects enzyme-substrate affinity (lower Km = higher affinity).
How do competitive and noncompetitive inhibitors affect Km and Vmax?
Competitive: increases apparent Km, Vmax unchanged (relieved by excess substrate). Noncompetitive: Vmax decreases, Km unchanged.
What does a Lineweaver-Burk (double-reciprocal) plot show?
A plot of 1/v versus 1/[S] giving a straight line: y-intercept = 1/Vmax, x-intercept = -1/Km, slope = Km/Vmax. Used to determine kinetic constants and inhibition type.
Define allosteric regulation of enzymes.
Regulation in which an effector molecule binds at a site other than the active site, changing enzyme conformation and activity; allosteric enzymes typically show sigmoidal (cooperative) kinetics.
What is feedback (end-product) inhibition?
The final product of a metabolic pathway inhibits an early (often the first committed) enzyme, preventing overaccumulation of product and conserving resources.
Name four mechanisms enzymes use to catalyze reactions.
Acid-base catalysis, covalent catalysis, metal-ion catalysis, and catalysis by proximity and orientation (and transition-state stabilization).
Contrast the lock-and-key and induced-fit models of enzyme action.
Lock-and-key: the active site is a rigid, exact complement to the substrate. Induced-fit (Koshland): substrate binding induces a conformational change in the enzyme to optimally fit and catalyze the reaction.
What are isozymes (isoenzymes)? Give an example.
Different molecular forms of an enzyme that catalyze the same reaction but differ in structure, kinetics, or tissue distribution; e.g., lactate dehydrogenase (LDH) exists as five isozymes (combinations of H and M subunits).
What does a Ramachandran plot display, and which regions are favored?
It plots backbone dihedral angles phi (C-N rotation) versus psi (C-C rotation) for each residue. Favored (allowed) regions correspond to the right-handed alpha-helix and beta-sheet; most other combinations are sterically forbidden.
Give the defining hydrogen-bonding pattern and rise of the right-handed alpha-helix.
Each backbone C=O hydrogen bonds to the N-H four residues ahead (i to i+4); ~3.6 residues per turn, rise ~0.54 nm per turn (0.15 nm per residue).
Compare A-, B-, and Z-DNA helices.
B-DNA: right-handed, most common physiological form, ~10 bp/turn. A-DNA: right-handed, shorter/wider, found in dehydrated/RNA-DNA hybrids, ~11 bp/turn. Z-DNA: left-handed, zigzag backbone, occurs in GC-rich alternating sequences, ~12 bp/turn.
Define protein domains, motifs, and folds.
A motif (supersecondary structure) is a small recurring arrangement of secondary structures (e.g., helix-turn-helix, beta-hairpin). A domain is an independently folding, often functional unit. A fold is the overall 3D arrangement/topology of secondary structures.
Describe the cloverleaf secondary structure of tRNA and its key functional sites.
tRNA folds into a cloverleaf with the acceptor stem (3' CCA end that carries the amino acid), the D arm, the anticodon arm (anticodon reads the mRNA codon), and the TψC arm; it folds into an L-shaped 3D structure.
What is microRNA (miRNA) and how does it regulate gene expression?
miRNA is a small (~22 nucleotide) non-coding RNA that base-pairs with complementary sequences (usually in the 3' UTR) of target mRNAs, causing translational repression or mRNA degradation via the RISC complex.
Compare the antiparallel beta-sheet with the parallel beta-sheet.
In an antiparallel sheet, adjacent strands run in opposite directions giving straight, well-aligned (more stable) hydrogen bonds; in a parallel sheet, strands run the same direction giving bent, angled hydrogen bonds and it is typically less stable.
What this deck covers
The Molecules And Their Interaction Relevant To Biology deck follows the CSIR NET Life Sciences Molecules And Their Interaction Relevant To Biology syllabus — 10 chapters and 37 topics — so questions land on material that is genuinely examinable rather than trivia around it. That works out to roughly 5.1 cards per chapter.
Answers are written to be recallable, not just readable — averaging about 183 characters, which is long enough to carry the reasoning and short enough to say out loud.
A deck like this earns its keep on the second and third pass. Read the syllabus first so you know the shape of the subject, then use the cards to find the specific facts that have not stuck.
Molecules And Their Interaction Relevant To Biology flashcards FAQ
How many Molecules And Their Interaction Relevant To Biology flashcards are in this CSIR NET Life Sciences deck?
51 cards. This page previews 24 of them, sampled evenly across the deck so you can judge the difficulty before installing anything.
Are these CSIR NET Life Sciences flashcards free?
Yes. The preview here is free to read with no signup, and the full 51-card deck is free inside the Examius app.
What do the Molecules And Their Interaction Relevant To Biology cards cover?
They follow the CSIR NET Life Sciences Molecules And Their Interaction Relevant To Biology syllabus — 10 chapters and 37 topics — so the questions track what is actually examinable.
How should I use these flashcards?
Read the syllabus first so you know the shape of the subject, then drill the deck. Examius schedules each card with spaced repetition, so cards you keep missing come back sooner and ones you know drift further apart.