What is the role of radula in molluscs?
Buccal cavity contains a rasping organ that helps in feeding, the radula with transverse rows of teeth. Radula helps in scratching and scraping the food.
Which of the following is not correct?
(a) Robert Brown discovered the cell.
(b) Schleiden and Schwann formulated the cell theory.
(c) Virchow explained that cells are formed from pre-existing cells.
(d) A unicellular organism carries out its life activities within a single cell.
Describe the role of liver, lungs and skin in excretion.