ch. 16.4-5

Question 1

starch hydrolysis

Answer 1

polysaccharide in food, mouth amylase.
disaccharide, small intestine maltase.
monosaccharide, absorbed into bloodstream from small intestine

Question 2

can humans digest cellulose?

Answer 2

no, don’t have cellulase

Question 3

lactose

Answer 3

sweet tasting disaccharide present in milk of mammals

Question 4

lactase

Answer 4

hydrolyses lactose to glucose and galactose.

found in small intestine.

Question 5

lactose intolerant

Answer 5

inability of body to digest lactose, a disaccharide in milk.

usually due to deficiency of lactase

Question 6

glycaemic index

Answer 6

scale that ranks food according to its effect on blood sugar levels overtime.
measure rate of hydrolyses of carbohydrates in food

Question 7

low GI

Answer 7

slow hydrolysis.
prolonged digestion.
slow rise in blood sugar

Question 8

high GI

Answer 8

fast hydrolysis.
rapid digestion.
rapid rise in blood sugar

Question 9

normal range for blood sugar

Answer 9

4-8 moll-1

Question 10

type 2 diabetes

Answer 10

resistant to insulin or do not produce enough insulin to keep up with glucose release

Question 11

type 1 diabetes

Answer 11

dependent on insulin to control their blood sugar levels within safe range

Question 12

bile

Answer 12

greenish-brown alkaline fluid that aids digestion.

secreted by liver and stored in gallbladder

Question 13

where is bile secreted to?

Answer 13

passes through bile duct into duodenum to emulsify triglyceride

Question 14

emulsion

Answer 14

suspension of small droplets of one liquid in another

Question 15

rancid

Answer 15

describes a lipid that has broken to produce smaller molecules with noxious odours and flavours

Question 16

oxidative rancidity

Answer 16

process by which lipids deteriorate and become rancid.

leads to formation of unpleasant smelling and potentially harmful short chain aldehydes and ketones

Question 17

process of rancidity

Answer 17

c-c double bonds in unsaturated fats can be reactive with enzymes, water, oxygen and light.
hydrocarbon chain can break into smaller molecules with unpleasant odours / flavours

Question 18

autoxidation

Answer 18

reaction with oxygen that occurs in the open air or in the presence of oxygen and forms peroxides or hydroperoxides.
involve free radicals

Question 19

free radical

Answer 19

molecules of atoms with unpaired outer-shell electrons.

unstable and highly reactive

Question 20

antioxidant

Answer 20

substance that slows rate, or delays oxidation of another substance

Question 21

process of antioxidants

Answer 21

donating a hydrogen atom to peroxide radicals, preventing them from reacting with nearby molecules