The contraction of the diaphragm and the external intercostal muscles begins inspiration. Explain exactly what happens, in terms of volume and pressure changes in the lungs, when these muscles contract
What will be an ideal response
With contraction of the diaphragm, the height of the thoracic cavity increases. Contraction of the external intercostal muscles expands the diameter of the thorax. With an increase in volume of the thorax, the intrapulmonary volume increases, causing a drop in pressure relative to atmospheric pressure. Air rushes into the lungs along this pressure gradient until intrapulmonary and atmospheric pressures are equal.
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Central adaptation refers to
A) the decline in activity of peripheral receptors when stimulated. B) a characteristic of phasic receptors. C) inhibition of nuclei located along a sensory pathway. D) increases in conscious perception of a sensory stimulus. E) a change in motor receptivity of a neuron.
Which of the following is not considered a factor in influencing a reaction?
A) temperature B) concentration C) particle size D) time
This figure shows the bones of the ankle and foot. Which bone does the number 1 indicate?
A. Middle phalanx of the hallux B. Distal phalanx of the hallux C. Distal phalanx of the pollex D. Proximal phalanx of the pollex E. Proximal phalanx of the hallux
Define oocyte
A) Oocyte is an immature female gamete. B) Oocyte is a mature female gamete. C) Oocyte is the nest a gamete develops in. D) Oocyte is the stage of a female gamete during ovulation. E) Oocyte is the empty follicle after ovulation.