Identify the structure indicated by arrow labeled “B”

Label “A” in the diagram below.  

Give the function of the histological structure bound by the yellow arrow.

Identify the blood vessel indicated by the arrow labeled “B”.

Identify the blood vessel at the tip of the arrow labeled “B”.                                      

The structures at the arrows play a role in what process?  

Name the valve labeled “C” and be very specific.

What does the electrical signal labeled “A” on the ECG lead to in the cardiac cycle?  

Identify the blood vessel indicated by the arrow labeled “C”.

What can you find in the section of the tube labeled “B”.