The circulatory pattern,in which blood pumped by the heart passes through large vessels into open spaces or body cavities called sinuses,is called $.......$ and it is found in $........$

Identify whether the given statements are true or false for double circulation.
$I$. It prevents the mixing of oxygenated and deoxygenated blood in the heart.
$II$. It circulates only oxygenated blood through the heart.
Choose the correct option accordingly.

What is the circulatory system called that begins and ends in capillaries?

Hepatic portal system is present in

Mammals are said to have a "double circulatory system". This means

Which alphabet indicates the dorsal aorta in the given diagram?