Fill in the blanks. Blue green algae fix …………….directly from air and enhance fertility of soil.

Blue-green algae belong to

Fill in the blanks. Burning of wood and coal causes…………….. Of air.

Fill in the blanks. The planet which is farthest from the sun is ………………….

Fill in the blanks: Plant fibres are obtained from____and ____.

Red algae differs from green and brown algae in

Fill in the blanks Calculate the length of tangent from a point 15cm away from the centre of a circle of radius 9cm .

Fill in the blanks using the words from the list appended with each statement Viscosity of glass…….with temperature,whereas viscosity of liquids…..with temperature (increases/decreases)

Cell division in blue green algae is similar to that in