UWorld_1.14

Question 1

Morphine: MOA

Answer 1

• agonist @ Mu opioid receptors
• Mu opoid receptors = GPCR ==>
  
  • activation of K channels ==> increased K efflux
  • ==> hyperpolarization ==> termination of pain signaling from nerves

Question 2

uteric bud (embryonic structure) ==>

Answer 2

• collecting system of kindey:
  
  • collecting tubules and ducts
  • major and minor calyces
  • renal pelvis
  • ureters
• mesoderm ==> urogenital ridge ==> nephrogenic cord ==> mesonephros ==> metanephros (begins w/uteric bud) ==> kidney structures

Question 3

metanephric mesoderm (embryonic) ==> ?

Answer 3

• formation induced by penetration of uteric bud into mesoderm
• forms: glomerulus, bowman’s capsule, proximal tuble, LOH, distal convoluted tubule
  ​

Question 4

“Maternally-inherited” =

Answer 4

• mitochondiral inheritance
• passed only from mother ==> offspring

Question 5

Important mitochondrial-inherited diseases

Answer 5

• leber hereditary optic neuropathy = bilateral vision loss
• myoclonic epilepsy w/ragged-red fibers
  
  • myoclonic seizures
  • myopathy w/exercise
• mitochondrial encephalopathy w/lactic acidosis and stroke-like episodes (MELAS)

Question 6

heteroplasmy definition

Answer 6

• mixing of genetic material
• commonly occurs in mitochondrial-inheritance ==> random distribution of mitochondria in daughter cells; some w/damaged mtDNA and some w/normal mtDNA ==>
• clinic variability of disease expression

Question 7

General characteristics of meningiomas

Answer 7

• most common brain tumor in adults
• occur adjacent to cerebral surface
• arise from arachnoid villi
• benign and slow-growing
• characteristics finding: psammoma body

Question 8

Common locations and neuro impacts of meningiomas

Answer 8

• near parasaggital cortex (near falx cerebri) ==> contralateral leg spasticity and paralysis
• near olfactory groove ==> H/A and anosmia
• lateral convexity of hemisphere ==> hand/face motor issues