What is meant by the term osmoregulation?
Osmoregulation is a homeostatic mechanism that regulates the optimum concentration of water and salts in the tissues and body fluids. It maintains the internal environment of the body by water and ionic concentration.
Describe the role of liver, lungs and skin in excretion.
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 structure of the following with the help of labelled diagrams.
(i) Nucleus
(ii) Centrosome
Write the difference between:
(a) Actin and Myosin
(b) Red and White muscles
(c) Pectoral and Pelvic girdle