Q4. Assertion: in haemodialysis, nitrogenous wastes move freely out of the blood. Reason: the dialysing fluid has no nitrogenous wastes, and the porous cellophane membrane passes molecules down their concentration gradient. Are both true, and does the reason explain the assertion?
Both are true, and the reason explains the assertion (NCERT pages 213–214).
Q5. Through which vessel is the cleared blood returned to the body in haemodialysis?
A vein, after anti-heparin is added (NCERT page 214). Beyond the NCERT text: in practice the blood leaves and returns through a vascular access, an AV fistula, an AV graft or a catheter (NIDDK, Hemodialysis; public domain).
Q6. What is glomerulonephritis?
Inflammation of the glomeruli of the kidney (NCERT page 214).