Puffer fish poison blocks voltage-gated sodium channels like a cork. What effect would this neurotoxin have on the function of neurons?
A) Neurons would depolarize more rapidly.
B) Action potentials would lack a repolarization phase.
C) The absolute refractory period would be shorter than normal.
D) The axon would be unable to generate action potentials.
E) None, because the chemically gated sodium channels would still function.
D
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An oncologist is reviewing a CT scan of a 74-year-old man with newly diagnosed hepatocellular carcinoma. He locates the affected quadrate lobe of the liver that:
(A) Lies between the IVC and ligamentum venosum (B) Receives blood from the right hepatic artery (C) Drains bile into the left hepatic duct (D) Is a medial superior segment (E) Is functionally a part of the right lobe
Which vitamin deficiency is the most common worldwide?
A) Vitamin A B) Vitamin D C) Vitamin E D) Vitamin B6 (pyridoxine) E) Vitamin C
The concentrations of substances in the plasma, in the glomerular filtrate, and in urine differ in what way?
A) Plasma contains the most water, glomerular filtrate contains less water, and urine contains the least. B) Plasma and glomerular filtrate are virtually identical, but urine contains proportionately more waste products. C) Plasma differs from glomerular filtrate and urine, which have virtually identical concentrations of substances. D) All three have the same concentrations of nutrients and waste materials, but differ in the amount of proteinaceous material they contain.
Found in the urinary bladder, ________ epithelium resembles ________ epithelium, but the apical cells are rounded, not flattened
A) transitional; simple cuboidal B) stratified squamous; pseudostratified C) simple columnar; pseudostratified D) stratified squamous; stratified columnar E) transitional; stratified squamous