Down syndrome is due to an extra
A. X chromosome.
B. autosome.
C. Y chromosome.
D. X chromosome or an extra Y chromosome.
Answer: B
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What kind of heat loss occurs continually from the linings of the respiratory airways and from the surface of the skin?
a. radiation b. conduction c. evaporation d. dissipation e. convection
The Drug Enforcement Agency requires separate inventory and use records to be kept for a. all oral medications
b. all injectable medications. c. schedule I and II controlled substances. d. all controlled substances.
When an impulse arrives at the knob of the motor neuron, calcium
A. enters through active transport pumps and triggers the release of transmitter. B. enters through voltage-gated channels and triggers the release of transmitter. C. is released from synaptic vesicles. D. exits through voltage-gated channels and triggers transmitter release. E. exits through active transport pumps and brings transmitter with it.
Which type of cell makes up about 90% of the alveolar surface?
A. Type II pneumocytes B. Type I pneumocytes C. Macrophages D. Ciliated simple squamous epithelial cells