Drugs! Experiments! Buffers!
Which technique selectively amplifies a specific DNA sequence?
PCR
GnRH, oxytocin, and TRH receptors couple to which G protein?
Gq
Which syndrome results from deletion of 5p and produces a high-pitched cat-like cry?
Cri-du-chat syndrome
During prolonged fasting, RBCs cannot use ketone bodies. Why?
They lack mitochondria
PEPCK consumes which high-energy nucleotide when converting oxaloacetate to PEP?
GTP
A researcher wants to detect a specific chromosomal microdeletion using a fluorescent probe.
FISH
Erythropoietin signals through which pathway?
JAK/STAT
A short female has a webbed neck, widely spaced nipples, and coarctation of the aorta. What is the karyotype and diagnosis?
45,X — Turner syndrome
During prolonged starvation, which organ begins extensively using ketone bodies?
Brain
Phenylalanine hydroxylase requires which cofactor?
Tetrahydrobiopterin (BH4)
A patient with acute gout receives a drug that binds tubulin, prevents microtubule polymerization, and impairs neutrophil migration.
Colchicine
Insulin activates PI3K-AKT in skeletal muscle, causing membrane translocation of which transporter?
GLUT4
Intellectual disability, cheerful personality, hypercalcemia, and elfin facies result from a deletion involving elastin on chromosome 7.
Williams syndrome
What happens when glycogen synthase is phosphorylated?
Glycogenesis decreases
Hyperammonemia without elevated orotic acid due to failure of the first mitochondrial urea-cycle step indicates deficiency of what enzyme?
CPS-1
A patient with a urea-cycle disorder receives a nitrogen-scavenging drug providing an alternative route of nitrogen excretion. Name one.
Benzoate, phenylacetate, or phenylbutyrate
Pertussis toxin prevents Gi from inhibiting adenylyl cyclase. What happens to cAMP?
Increases
An X-linked carrier is unusually symptomatic because most cells inactivated her normal X chromosome.
Skewed X-inactivation / lyonization
High malonyl-CoA prevents simultaneous fatty-acid synthesis and β-oxidation by inhibiting which enzyme?
CPT-I
Developmental delay, downward lens subluxation, and recurrent thrombosis suggest deficiency of which B6-responsive enzyme?
Cystathionine synthase
Free heme binds CO much more strongly than intact hemoglobin. Which amino acid residue reduces CO affinity by forcing CO into a less favorable geometry?
Distal histidine (His E7)
A tumor loses the phosphatase that normally converts PIP3 back to PIP2, opposing PI3K signaling. Name it.
PTEN
Different proportions of normal and mutant mitochondrial DNA produce dramatically different disease severity among relatives. What phenomenon?
Heteroplasmy
During prolonged fasting, the liver makes ketones but cannot utilize them because it lacks which enzyme?
Thiophorase
α₁-antitrypsin deficiency causes premature emphysema through unopposed activity of which enzyme?
Elastase