Question

When the cuff pressure is high enough to keep the brachial artery closed, no blood flows through it and no sound is heard. When cuff pressure decreases and is no longer able to keep the artery closed, blood is pushed through, producing turbulent blood flow and a sound. Systolic pressure is the pressure at which the first korotkoff sound is heard. At first, the artery is closed during systole but as cuff pressure continues to decrease, the artery partially opens. Turbulent blood flow during systole produces pulse sounds, although the pitch of the sounds changes as the artery becomes more open?

Answer 1

Answer:

Memory-based acquired immunity evolved in higher vertebrates based

on the ability to differentiate foreign organisms (e.g., pathogens) from self-

cells. While we still do not understand the basis of this, two corollaries of

this ability have to be understood. One, higher vertebrates can distinguish

foreign molecules as well as foreign organisms. Most of the experimental

immunology deals with this aspect. Two, sometimes, due to genetic and

other unknown reasons, the body attacks self-cells. This results in damage

to the body and is called auto-immune disease. Rheumatoid arthritis

which affects many people