Before DNA replication can occur, the double-stranded DNA must first –

Before replication can occur, the length of the DNA double helix about to be copied must be unwound.

the answer is c.) there is a warm front in region a and a stationary front in region b.

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.