State the functions of carbohydrates, proteins and fats

Explain why most food must be digested

Explain what is meant by digestion

Explain what are enzymes and why enzymes are needed in digestion

Briefly state the function of the enzymes amylase, protease and lipase

Describe the digestive system and how it helps in the digestion of food

Briefly state the importance and function of the liver and the pancreas in digestion

Describe how the digested food is absorbed into the bloodstream

Define excretion as the removal of toxic materials and the waste products of metabolism from organisms

Describe the removal of carbon dioxide from the lungs

Identify on diagrams and name :

	kidneys
	ureters
	bladder
	urethra

state the function of each (the function of the kidney should be described simply as removing urea and excess water from the blood)