Q4. Assertion: the liver helps in excretion. Reason: bile carries substances such as bilirubin, biliverdin and degraded steroid hormones, which mostly pass out with the digestive wastes. Are both true, and does the reason explain the assertion?
Both are true, and the reason explains the assertion (NCERT page 213).
Q5. Name three substances found in sweat.
NaCl, small amounts of urea, and lactic acid, in a watery fluid (NCERT page 213).
Q6. Besides the kidneys, lungs, liver and skin, which body fluid can carry small amounts of nitrogenous wastes?
Saliva (NCERT page 213).