Running head: Hassan's Story- The Appendicular Skeleton

The Appendicular Skeleton

Hassan's Story

A- Which clue would tell Stefan which scapular surface was anterior and which was posterior? What is the name of the shallow, oval socket of the scapula that Stefan placed next to the humerus?

The clue that Stefan could use is that there is a prominent ridge called the spine that runs diagonally across the posterior surface of the scapula. Or he could use the medial border of the scapula, it's the longest of three borders and extends from the superior to the inferior angle. This border presents an anterior and posterior lip and an intermediate narrow area. Stefan would have also placed the glenoid cavity next to the humerus while aligning the scapula.

B- Which bone is Stefan referring to as the "collarbone"?

The bone that Stefan is referring to as the "collarbone" is the clavicle. It is a long bone that serves as a strut between the scapula and the sternum. C- Which surface markings could Stefan use to distinguish the right humerus from the left?

Stefan can hold the bone so that the capitulum and trochlea face him, which would indicate it was the anterior. This would help him distinguish between the right humerus from the left.

D- Why would Stefan think that an enlarged right deltoid tuberosity might indicate right-handedness?

The right deltoid tuberosity will grow larger and more defined on your dominant side. Since I am right handed, my right arm is slightly larger than my left. E- What is the location of the pubic symphysis Stefan refers to in the story?

The pubic symphysis that Stefan referred to is the joint between the two hip bones that is made up of fiberocartilage. F- Which adaptation would have taken place in the pubic symphysis of the female skeleton during the later stages of her pregnancy in preparation for the birthing process?

In the later stages of pregnancy the hormone relaxin increases the flexibility of the pubic symphysis to ease delivery of the baby. G- What clues could Stefan have used to identify the gender of the pelvis?

The clues he could use are male pelves are generally larger, heavier, and have more prominent markings. Female pelves are generally wider and shallower, looking more oval like to accommodate the passage of an infant's head at birth.

H- How would Stefan have distinguished between the right and the left hip bones?

Stefan would have distinguished between the right and left hip bones by looking at the false pelvis. He would've also used the alignment of the pelvic brim to make the true pelvis line up. I- Would the bones of each hip bone be fused in the female child's skeleton?

Throughout childhood the pelvis is made of many smaller bones that eventually fuse during adulthood to form a more rigid pelvis. So the answer would be no to the bones of each hip bone being fused in the female child's skeleton.

References

Jenkins, G, & Tortora, G. (2013). Anatomy and Physiology from Science to Life. The Appendicular Skeleton , 8, 220-243.