A ten-year-old boy falls from a tree, but manages to slow his descent somewhat by grabbing onto limbs he passes on the way to the ground. When he finally lands, he experiences some soreness on the buttocks, but otherwise does not think he is hurt until he discovers that he cannot move his fingers easily or accurately. What structures have been damaged?
What will be an ideal response?
The paralysis of the hand has occurred because of damage to the lower trunk of the brachial plexus, which was stretched when the boy grabbed onto branches to slow his fall from the tree. This trunk gives rise to C8 and T1, the nerves that control the intrinsic muscles of the hands.
You might also like to view...
Thymic hormones
A. stimulate T-lymphocyte maturation and differentiation. B. are produced by the cortical lymphocytes. C. stimulate the activity of nurse cells. D. are secreted in response to stimulation by activating hormones from the pituitary gland. E. are stored in thymic corpuscles prior to release.
Effects of hypokalemia include
A) diabetes. B) muscle weakness. C) sweating. D) acne.
One advantage of signaling pathways involving the generation of second messengers has compared to a signaling pathway that utilizes the influx of ions is
a. the former are much faster in terms of generating cellular responses to first messengers. b. the former are slower in terms of generating cellular responses, allowing cells to be more circumspect in their response to chemical signals. c. the former require less first messenger to elicit a response, since they allow for signal amplification. d. the former require more first messenger to elicit a response, allowing for more rapid termination of the signaling event. e. none of these.
Precise spelling is important in anatomy because ________
A) there are many different ways to spell certain terms B) there are many similar terms in anatomy that refer to different structures C) it's easier to remember acronyms when spelled correctly D) it's important to practice language skills E) eponyms are difficult to memorize