Revision 3

Complete the sentences about air.

Use the words from the list. Each word may be used once, more than once or not at all.

compound, methane, mixture, nitrogen, oxygen

1) Air is a ........................................ .

2) The gas with the largest percentage in clean air is ........................................ .

3) 21% of clean air is ........................................

Water is a raw material for photosynthesis.

Complete these sentences about the movement of water in a plant.

1) Water enters the roots through root ........................................ cells.

2) Water is transported from the roots to the leaves in ........................................ vessels.

3) Water is then lost from the leaves through pores (holes) called ........................................ .

Complete the sentences to describe the pathway taken by water through the leaf.

Choose words from the list. Each word may be used only once.

diffusion, evaporation, osmosis, transmission, transpiration

1) Water moves from the xylem to the air spaces in the leaf by ……………………………………………… from the surface of mesophyll cells.

2) The water vapour then passes out of the stomata by the process of ……………………………………………… .

3) This loss of water vapour from the leaves is called ……………………………………………… .

Complete these sentences about blood vessels from the circulatory system.

1) The artery has a much ............................................. wall compared to the vein.

2) This is because the artery transports blood away from the ............................................. at high pressure

The bus uses batteries to supply energy to the electric motors that drive the wheels of the bus.

Complete the sentence by identifying the energy transfers that happen when the bus is moving.

Energy is transferred from ..................................... potential energy in the batteries to ..................................... energy in

the motors and then to ..................................... energy of the motors and the moving bus.

Complete these sentences about the digestion of food in the alimentary canal.

Choose words from the list. Each word may be used once, more than once or not at all.

absorption, egestion, ingestion, insoluble, osmosis, soluble

1) Food is taken into the mouth by the process of .......................................... .

2) Digestion breaks down large .......................................... food molecules into small water .......................................... food molecules.

3) The small molecules then move through the wall of the intestine by the process of .......................................... .