Venous ulcers are typically caused by chronic venous insufficiency, so they tend to be shallow with an irregular, poorly defined edge. The wound bed often has granulation tissue and there is usually significant drainage due to edema and venous stasis in the surrounding skin. This shallow, irregular pattern reflects the way venous hypertension causes tissue breakdown around the ankle, rather than the deep, punched-out appearance and pale base seen with arterial ulcers or the necrotic, gangrenous look that can accompany severe infection or ischemia.

The key idea is how fats are absorbed after a meal. Fats in the intestinal lining are reassembled into triglycerides and packaged into chylomicrons, which enter the lacteals—special lymphatic vessels in the intestinal villi. From there, these lipid-containing particles travel through the lymphatic system before entering the bloodstream. This is why lipids are the correct answer: the lymphatic system is the route for absorbing dietary fats. In contrast, water and most proteins move into blood capillaries for transport via the portal circulation, and vitamins follow their own routes, often with fats, but the primary absorber among the options is lipids.

An abnormal extra heart sound can come from valve mechanics, and the ejection click is a classic example. It’s a brief, high-pitched sound heard early in systole, right after S1, produced when a semilunar valve (usually the aortic or pulmonary valve) opens abruptly against a stiff or edematous opening. This sound points to valvular abnormality, such as a bicuspid aortic valve or residual stenosis, and it has a characteristic timing that helps distinguish it from normal S1/S2 sounds. Other options describe sounds that are not normal: a normal heart sound would not be an extra sound, and a systolic murmur is also abnormal, though of a different type. A friction rub is indeed abnormal, signaling pericarditis, but the ejection click is the prototypical discrete abnormal systolic sound associated with valve opening, which is why it’s identified as the abnormal heart sound in this context.

Arteries are the high‑pressure conduit of the circulatory system. When the heart contracts, it ejects blood into the arteries with strong force, creating high pressures that push blood forward. The arterial walls are thick and elastic, so they recoil between heartbeats and help sustain that pressure, keeping the arterial system much higher in pressure than the venous side. In contrast, veins operate under low pressure and rely on valves and surrounding muscles to help return blood to the heart. While arterial pressure does fluctuate with each heartbeat (peaking during systole and dipping during diastole), the overall system is best described as high pressure.