key concepts ++ enzymes and nutrition

Question 1

what are enzymes ?

Answer 1

enzymes are proteins that act as biological catalysts

Question 2

give examples of enzymes and where they are found in the human body

Answer 2

• amylase breaks down starch and carbohydrates into sugars
• protease breaks down proteins into amino acids (pancreas + small intestine)
  lipase breaks down lipids (fats and oils) into glycerol and fatty acids (pancreas + small intestine)

Question 3

what are the subunits of lipids made from?

Answer 3

fatty acids, glycerol (and sometimes phosphate groups)

Question 4

what are the subunits of carbs called ?

Answer 4

monosaccharides (individual sugar molecules) e.g. glucose, fructose, galactose, lactose, etc.

Question 5

what are the subunits fo proteins ?

Answer 5

amino acids

Question 6

how do enzymes work ?

Answer 6

Enzymes are proteins that function as biological catalysts. So, they are molecules that speed up a chemical reaction without being changed by the reaction. Carbohydrates, proteins and lipids are large molecules that are needed by the body for growth, repair and metabolism. They are found in our food. These molecules are too large to pass from the intestine into the blood, so digestive enzymes break them down into smaller molecules. Once in the body, different enzymes use these raw materials to synthesise larger molecules and speed up the rate of reaction.

Question 7

why is catalysis by enzymes is important for life processes ?

Answer 7

because reactions happen much faster