Why do knuckles crack when you bend them

The noise of cracking or popping in our joints is actually nitrogen bubbles bursting in our synovial fluid

Explanation:

It is because synovial fluid lubricates your joints like motor oil in a car's engine, reducing friction and preserving our cartilage.

PLS MARK BRAINLIEST :D

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.