Answer:
Superior vena cava
Explanation:
Of the two vena cava, the superior vena cava is the large vein without valves that is responsible for conveying de-oxygenated blood from the upper extremities and body (neck, chest, arm and head) above the diaphragm to the right artrium.
Although the superior vena cava is a large vein, it also short; it is about 2 cm wide and 7 cm long.
When there is an obstruction of the superior vena cava, it can result to the enlargement of the veins and could lead to chest pain and breathlessness.
Answer:
An active transport requires energy, a passive transport does not.
That's all! Hope that helps :)
Answer:
The answer is single replacement :)
A swamp involves the biosphere and the hydrosphere
a farm involves the biosphere and the atomosphere
