Main Nutrirents Groups

Question 1

A nutrient is a component of the diet needed to sustain life

Answer 1

Carbohydrates 
Lipids 
Proteins 
Minerals 
Vitamins 
Water 
Fibre

Question 2

What nutrients need digesting?

Answer 2

Proteins, fats and carbs from the diet need to be digested before they can be absorbed

Question 3

Physical digestion

Answer 3

Is produced by the mechanical activity of the gut - food retains its chemical structure but it’s surface area is increased to expose more sites to enzyme action

Question 4

Chemical digestion

Answer 4

By digestive enzymes

Enzymes in the lumen (secreted) or on the surface of cells lining the lumen

Question 5

Protein digestion

Answer 5

(Macromolecules is broken into amino acids in a series of stages

Protein - polymer ( many molecules - many unit )
Amino acids - monomers (single unit - molecules)

The enzymes which digest proteins are called proteases - pepsin, trypsin, chymotrypsin

Each enzyme has an optimum PH, temperature in which it works best

Question 6

Carb digestion

Answer 6

Starch must be broken down by glucose via a series of steps

Amylase is an important enzyme in starch digestion

Disaccharides to their constituents monacchardies e.g lactase, Maltase

Question 7

Triglyceride digestion

Answer 7

Fats and oils are neutral fats made up from molecules called triglycerides
These are digested by lipases into glycerol and 3 fatty acid molecules