Principles Flashcards
Describe the four types of protein structure.
I: amino acid chain
II: hydrogen bonds etc
III: R group interactions
IV: Co-operativity between subunits
Define the terms endergonic/exergonic and endothermic/exothermic, and catabolism/anabolism.
Exothermic - releases energy Endothermic - takes in energy Exergonic - spontaneous Endergonic - not spontaneous Catabolism - breakdown, exothermic Anabolism - buildup (Adding), endothermic
Give the Henderson-Hasselbach equation.
pH = pKa + log([A]/[HA])
What are the main enzymes of DNA replication? How is DNA typically stored?
Helicase - unzips; Primase - forms primers; DNA Polymerase - adds bases; Ligase - glues fragments; topoisomerase - zips DNA back together.
-ve DNA stored wrapped around +ve histone proteins and chromosomes.
Describe the key aspects of the central dogma.
Define degenerate and unambiguous.
TFIID recognizes TATA box 15-20 proteins upstream of beginning site. RNA pol II synthesises RNA. T bases are replaced by U. C-G hairpin and poly U-site cleave new RNA strand. Introns are removed and G cap with poly A tail is added.
mRNA goes through ribosomes (EPA sites) until stop codon binds release factor (not tRNA!!!) causing dissociation.
Degenerate: amino acids have multiple codons.
Unambiguous: each codon codes only one amino acid.
Define the terms cofactor, coenzyme, apoenzyme, holoenzyme, and the Michealis constant.
Cofactor - a metallic accessory to an enzyme
Coenzyme - an organic accessory to an enzyme
Holoenzyme - enzyme with cofactor
Apoenzyme - enzyme without cofactor
Michaelis - [S] at which velocity of the reaction is exactly 50%.
Considering the Lineweaver-Burke plot, describe the difference between competitive and non-competitive inhibitors.
(X axis = 1/[S], y axis = 1/V; so x-intercept = 1/Km and y-int (c) = 1/Vmax)
Non-inhib and competitive have same Vmax but different Km.
Non-comp has same Km but lower Vmax.
Name the rate-limiting enzymes of glycolysis, glycogenesis, glycogenolysis, lipogenesis, lipolysis, and the urea cycle.
PFK, glycogen synthase, glycogen phosphorylase, acetyl-coa carboxylase, HMG-CoA reductase, and carbamoyl phosphate synthase I
Name the final electron acceptor of respiration. Name also the quantity of electron transporters and ATP produced by each stage.
Oxygen (forming water). Glycolysis - 2xNADH
Krebs - 8xNADH, 2xFADH2
ATP - between 30-32
Define polymorphism and name the main nucleotide and chromosomal mutations.
Polymorphism - a prevalent (>1% population) genetic variant that does not necessarily cause disease.
Bases - nonsense, missense, silent, frameshift
Chromosomal - deletion, duplication (together this is aneuploidy), translocation, inversion
Name the five most common chromosomal disorders.
t13 - Patau's t18 - Edward's t21 - Down's 45X - Turner's 47XXY - Klinefelter's
Which cancers are associated with the oncogenes ABL, c-myc, n-myc, BCL-2, and RAS?
Chronic myeloid leukemia, Burkitt lymphoma, neuroblastoma, follicular lymphoma, pancreatic cancer
Name the genetic tests best used for smaller, then larger, genetic defects.
Smaller (bases) - Sanger and NGS (NGS > Sang)
Larger - PCR, aCGH (first line), FISH
Name the main side effects of each type of antibiotic.
Sulfonamides - SJS
Penicillin - hypersensitivity
Cephalosporins - c. diff
Glycopeptides and aminoglycosides (both -mycin) - ototoxicity and nephrotoxicity
Tetracyclines - grey staining, phototoxicity, hepatotoxicity. Do not use in < 16 years
Macrolides - P450 inhibition, QT lengthening
Quinolones - C. diff, prolongs QT
Name the gram negative and positive cocci and bacilli.
+ve cocci: strep, staph, and enterococci
-ve cocci: Neisseria sp., Moraxella sp.
+ve bacilli: ABCDL (actinomyces, bacillus anthracis, clostridium, diptheria, listeria)
-ve bacilli: everything else!
Describe the difference between endo- and exotoxin. Describe the three types of haemolysis and the main strep sp. which cause these.
Endotoxin is LPS released from -ve sp., while exotoxin is released from +ve.
Alpha (partial - green: pneumoniae + viridans sp.)
Beta (complete - yellow: pyogenes + agalactiae)
Gamma (no haemolysis - enterococci)
Think: yellow is further from dark red than green, so is more destruction.
Name the two main types of virus activation. Name the two techniques which are most used to discover viral aetiologies.
Lytic pathway and lysogenic pathway (replication vs quiescent).
PCR and electron microscopy (not light; too small)
Describe the three types of muscle, and how they work to contract.
Skeletal - striated, many nuclei, voluntary
Smooth - non-striated, one nucleus, non-voluntary
Cardiac - branched, striated, one nucleus
Gap (communicating) junctions allow electrolyte transfer. Actin (covered by tropomyosin, nailed down by troponin) is activated when Ca2+ causes troponin conformational change
Name the major event or name change that occurs in embryology at the following times: 0 hrs, 4 days, 5D, 7D, 10D, 16D, 3W, 4W, 7W, 8W.
0H - fertilization 4D - morula 5D - blastocyst (cytotrophoblast and embryoblast) 7D - implantation (usually posterior) 10D - bilaminar disc develops 3W - gastrulation (bi to tri) 4W - neurulation 7W - cloacal and oral membranes rupture 8W - embryo is now considered a foetus
State the time after fertilization at which these embryonic events occur:
morula, blastocyst, bilaminar disc formation, gastrulation, neurulation, rupture of cloaca and oropharynx, end of embryonic stage.
4D, 5D, 7D, 10D, 3W, 4W, 7W, 8W.
What are the three types of joint? Give examples of each.
Fibrous - skull sutures, teeth gomphoses, interosseous membrane of radius and ulna (syndesmoses)
Cartilaginous - 1ry: rib and sternum. 2ry: intervertebral and pubic symphesis
Synovial - everything else!
Name the peritoneal pouches, where ascitic fluid may collect.
Vesicouterine, rectouterine (Douglas), vesicorectal, and hepatorenal (Morrison).
Name the twelve cranial nerves and their functions (i.e. are they sensory, motor, or both?).
Which CNs transmit parasympathetic fibres to the body?
Oh oh oh, to touch and feel a girl’s vagina, ah heaven:
olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, (v)estibulcochlear, glossopharyngeal, vagus, accessory, hypoglossal.
Some say money matters but my brother says big brains matter more: SSMMBMBSBBMM.
CNs III, VII, IX, X (1973 - same as warfarin clotting factors +1).
Name the neurotransmitters of the ANS and their receptor categories, then give their subcategories with functions.
ACh - nicotinic and muscarinic NA - cholinergic M1 (Gq) - gastric acid M2 (Gi) - cardiac inhib M3 (Gq) - bronchoconstriction a1 - vessel smooth muscle a2 - neuronal b1 - cardiac excitation b2 - bronchodilation b3 - adipose breakdown Cholinergic is generally Gs
