Bloody or tarry stools refer to a stool sample thatâs either dark red or black in color. Bloody or tarry stools can indicate bleeding or other injuries in your gastrointestinal tract. You may also have dark, discolored bowel movements after eating dark-colored foods.
The longest vein in the body is the great saphenous vein, a superficial vein found in the leg.he deep veins are essenti â¦ ally a column of blood running from your head to you feet and so when one is standing are under high pressure. In order to keep this pressure away from the frail superficial veins the penetrating veins have valves.
The blood from the upper limb is returned to the heart by two sets of veins, superficial and deep. Both sets have valves, and both drain ultimately into the axillary vein. Superficial Veins (fig. 7-1).The superficial veins are highly variable, lie mostly in the subcutaneous tissue, and return almost all of the blood.Digital veins drain into a dorsal venous network in the hand, which leads to two prominent veins, the cephalic and the basilic.oth sets have valves, and both drain ultimately into the axillary vein. Superficial Veins (fig. 7-1). The superficial veins are highly variable, lie mostly in the subcutaneous tissue, and return almost all of the blood.