Which of these pairs shows the correct combination of bones and types of joints present in them? a. elbow – hinge joint b. elbow – ball and socket c. elbow – pivot joint.

b. the carbon cycle ensures living things have a source of hydrogen

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.