Biological Molecules & Diet- topic 5

Question 1

What elements are present in carbohydrates, proteins, and lipids?

Answer 1

Carbon, hydrogen, and oxygen (proteins also contain nitrogen)

Question 2

What are the monomers and polymers of carbohydrates

Answer 2

Carbohydrates: glucose → starch/glycogen

Question 3

What are the monomers and polymers of proteins

Answer 3

Proteins: amino acids → protein

Question 4

What are the monomers and polymers of lipids?

Answer 4

Lipids: fatty acids and glycerol → fats/oils

Question 5

What is a balanced diet?

Answer 5

A diet containing appropriate proportions of carbohydrate, protein, lipid, vitamins, minerals, water, and dietary fibre

Question 6

What are the functions of nutrients in a balanced diet?

Answer 6

Carbohydrates – Quick release energy
Lipids – Energy storage, insulation
Proteins – Growth and repair
Fibre – Healthy digestion and peristalsis
Vitamins – A: vision/skin, C: healing, D: bones
Minerals – Calcium: bones, Iron: haemoglobin
Water – Maintains osmotic pressure

Question 7

What affects a person’s energy requirements?

Answer 7

Age, activity levels, metabolism, pregnancy

Question 8

What food test is used for starch and what result indicates a positive test?

Answer 8

Iodine – turns from orange-brown to blue-black

Question 9

What food test is used for glucose and what is a positive result?

Answer 9

Benedict’s solution – turns from blue to orange-red

Question 10

What food test is used for lipids and what is a positive result?

Answer 10

Ethanol – forms a cloudy emulsion

Question 11

What food test is used for protein and what is a positive result?

Answer 11

Biuret reagent – turns from blue to purple

Question 12

What is a monomer?

Answer 12

A small, individual molecule

Question 13

What is a polymer?

Answer 13

A long molecule made up of many monomers