Human Nutrition/digestive system

Question 1

What is the function of fats in a balanced diet?

Answer 1

Energy storage; electrical insulation around the nerves; thermal insulation; protects organs

Question 2

What is the function of carbs in a balanced diet?

Answer 2

Sugars used in respiration to release energy; starch and glycogen are insoluble and store glucose without affecting water potential of cells

Question 3

Deficient disease of vitamin A?

Answer 3

Night blindness

Question 4

Which Enzyme digests starch to maltose?

Answer 4

Amylase

Question 5

How is the ileum specialised for absorption?

Answer 5

Villi on the ileum wall - increase surface area
Microvilli on the surface of the villi - increase surface area
Villi wall once cell thick - short diffusion distance
Capillaries in villi maintain a high concentration gradient.
Lacteal in villi - absorption of fats

Question 6

Which enzyme digests proteins to amino acids?

Answer 6

Proteases eg pepsin and trypsin

Question 7

How do you test the energy content of a food sample?

Answer 7

Measure out 25cm3 of water into a boiling tube.
Measure mass of food.
Measure starting temperature of food.
Set light to food using a Bunsen burner and hold under a boiling tube of water until it goes out.
Relight and repeat until it wont catch on fire.
Measure finishing temperature of water and calculate temperature change.
Energy content= volume of water X temperature change X 4.2 divided/ mass of food

Question 8

Function of pancreas in digestive system?

Answer 8

Produces the enzymes trypsin (protease), lipase and amylase

Question 9

What is the function of the oesophagus in the digestive system?

Answer 9

Moves food from mouth to stomach using waves of muscular contraction (peristalsis)

Question 10

Function of rectum in digestive system?

Answer 10

Stores the faces before egestion

Question 11

Function of vitamin A in a balanced diet?

Answer 11

Used to make rod cells in the retina

Question 12

Deficiency disease caused by lack of calcium?

Answer 12

Osteoporosis

Question 13

Function of stomach in digestive system?

Answer 13

Produces protease (pepsin) which digests protein. Produces hydrochloric acid which provides optimum conditions for the enzyme to kill bacteria

Question 14

Deficiency disease caused by lack of vitamin C?

Answer 14

Scurvy

Question 15

What enzyme digests maltose to glucose?

Answer 15

Maltase

Question 16

Function of protein in a balanced diet?

Answer 16

Enzymes; antibodies in immune system; hormones; transport proteins e.g. haemoglobin; muscle

Question 17

Function of calcium in a balanced diet?

Answer 17

Used to make bones (as calcium phosphate)

Question 18

Deficient disease caused by lack of iron?

Answer 18

Anaemia

Question 19

Function of bile?

Answer 19

emulsifys fats - breaks large droplets into smaller droplets, increasing surface area and rate of digestion by lipase. Neutralises stomach acid

Question 20

Function of vitamin D in a balanced diet?

Answer 20

Helps with absorption of calcium

Question 21

Function of duodenum in digestive system?

Answer 21

Final site of digestion of carbs, fats, proteins - produces the enzyme maltase

Question 22

Where is maltase produced?

Answer 22

Ileum

Question 23

Which enzymes digest fats to fatty acids and glycerol?

Answer 23

Lipase

Question 24

Function of vitamin C?

Answer 24

Helps form connective tissue, holding organs together

Question 25

Where is amylase produced?

Answer 25

Pancreas and salivary glands

Question 26

Where is protease produced

Answer 26

Stomach lining and pancreas

Question 27

Function of mouth?

Answer 27

Chews food to break it into smaller pieces. Produces saliva which makes it easier to swallow food. Saliva contains amylase

Question 28

Where is lipase produced?

Answer 28

Pancreas

Question 29

What is digestion?

Answer 29

Breakdown of large, insoluble molecules into small, soluble molecules

Question 30

Function of ileum?

Answer 30

Absorption of small, soluble molecules from the small intestine into the blood

Question 31

Egestion?

Answer 31

Removal of undigested food via the anus

Question 32

Function of iron?

Answer 32

Used to make haemoglobin

Question 33

Function of dietary fibre?

Answer 33

Keeps food moving through digestive system and prevents constipation

Question 34

Deficiency disease caused by lack of vitamin D?

Answer 34

Ricketts

Question 35

Function of colon?

Answer 35

Absorbs water into the blood

Question 36

Whee is bile made and stored?

Answer 36

Made in liver and stored in the gall bladder