Obtaining Nutrients from Food

Question 1

What are the main nutrient groups?

Answer 1

carbohydrates, proteins, fats, vitamins, minerals and trace elements, and water

Question 2

What are the 3 classifications of carbohydrates?

Answer 2

Monosaccharides - glucose, fructose, galactose. Cannot be further broken down.
Disaccharides - maltose (2 glucose molecules), sucrose (one glucose and one fructose), lactose (one galactose and one glucose). Two monosaccharides
polysaccharides - glycogen, starch, cellulose. Complex molecules from large numbers of monosaccharides

Question 3

What are some functions of carbohydrates?

Answer 3

• provision of heat and energy
• energy storage. Glycogen stored in liver and skeletal muscle. Fat stored under skin

Question 4

What digestive enzymes are used in the breakdown of carbohydrates?

Answer 4

starch to maltose uses amylase
maltose to glucose used maltase

Question 5

What are the two main types of fats?

Answer 5

Triglycerides - made up of fatty acids and glycerol. Known as saturated fats or unsaturated fats
cholesterol - obtained from dietary saturated fats. Used in manufacture of cell membranes and steroid hormones.

Question 6

What are the two types of cholesterol?

Answer 6

Low density lipoprotein (LDL) - bad cholesterol, can increase risk of CVD.
High density cholesterol (HDL) - good cholesterol

Question 7

What are some functions of fats?

Answer 7

• provision of heat and energy
• absorption, transport, and storage of fat-soluble vitamins
• used in manufacture of myelin sheath
• insulation
• to protect some organs

Question 8

What digestive enzymes are used in fats?

Answer 8

lipase - fat to fatty acids and glycerol

Question 9

What are essential and non-essential amino acids?

Answer 9

essential amino acids - cannot be synthesised by body an dmust be included in diet. Such as leucine, phenylalanine, tryptophan.
non-essential amino acids - can be synthesised by body. Such as alanine, cytesine, glutamine and tyrosine.

Question 10

What are amino acids used for?

Answer 10

• for growth and repair of body cells and tissues
• build new proteins
• to provide energy when carbohydrate and fat stores are depleted.

Question 11

What digestive enzymes are used in the breakdown of proteins?

Answer 11

pepsin - proteins to peptides
protease - peptides to amino acids

Question 12

What are water soluble vitamins?

Answer 12

Any excess amounts taken in that are not used by the body excreted in urine. Lack of storage capacity means food containing these need to be consumed daily.

Question 13

What are fat soluble vitamins?

Answer 13

Excess amounts stored in liver and fatty tissue until needed. Body does not excrete excess, vitamins more likely to cause toxicity if too much is ingested

Question 14

What are mineral and trace elements?

Answer 14

Minerals needed in small amounts for cells to function normally. Some minerals are needed in larger amounts than others.

Question 15

What are the functions of water?

Answer 15

• moistening food for swallowing
• regulating body temperature
• as major constituent of blood and tissue fluid, transporting substance around the body
• diluting waste products and toxins in the body
• supporting excretion of waste products in urine and faeces.