Question

RUNX2 mutations can limit the growth of these bones to their lateral ends, the lowest point of intramembranous ossification. These bones can indicate older ages than hand bones because, despite being the first to start ossifying, they only fuse past age 22. (-5[1])Troisier’s (“twahz-YAY’s”) sign is observed at the left of one of these bones by palpating above it to find a sentinel node. These long bones, which lack marrow, define the lines used to position the V3 and V4 leads in an (-5[1])EKG. (-5[4])Lymph enters the venous angle below the left of these bones (10[1])after passing (-5[1])through the thoracic duct. (-5[2])One of these bones is broken in half (-5[1])a percent (-5[1])of infants delivered vaginally. (10[2]-5[1])50 pounds of direct pressure will snap (10[1])these bones, (10[1]-5[1])which are often broken by falling with one’s arms out. (-5[1])For 10 points, name these curved bones (-5[1])that form the front of the shoulder girdle and connect at the sternum. (10[4])■END■ (10[7]0[4])

ANSWER: clavicles [or claviculae; accept collarbones or key bones; accept subclavian vein or supraclavicular lymph node]
<Biology>
= Average correct buzz position

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