Week 3

Question 1

what are the two types of carbohydrates?

Answer 1

simple and complex

Question 2

what are simple carbohydrates

Answer 2

monosaccharides (1 polymer)
disaccharide (2 polymers)

Question 3

what are complex carbohydrates

Answer 3

oligosaccharides (3-10 polymers)
polysaccharides (>10 polymers)

Question 4

what are three monosaccharides

Answer 4

glucose, fructose, galactose

Question 5

what is glucose

Answer 5

• blood sugar (dextrose)
• essential CHO- main source of energy for brain and nerves
• travels through our bloodstream
• what we break down into Krebs cycle to create ATP

Question 6

what is fructose

Answer 6

fruit sugar
sweeter than glucose or galactose

Question 7

what is galactose

Answer 7

• part of lactose (milk sugar)
• freed during digestion

Question 8

what are three disaccharides?

Answer 8

sucrose, lactose, maltose

Question 9

what is sucrose?

Answer 9

• fructose+glucose= sucrose
• table sugar

Question 10

what is lactose?

Answer 10

• galactose+glucose=lactose
• sugar in milk
• poorly digested in some (lactose intolerance)

Question 11

what is maltose?

Answer 11

• glucose+glucose = maltose
• produced when starch is broken down
• occurs during the fermentation process that yields alcohol

Question 12

what is hydrolysis

Answer 12

breaking a bond of two molecules using water

Question 13

how do you create a disaccharide?

Answer 13

using a condensation reaction- the removal of water can bind two polymers together

Question 14

what are three polysaccharides?

Answer 14

starch, fibre and glycogen

Question 15

what is starch?

Answer 15

source of glucose
storage form of glucose in plants

Question 16

what do we do with fibre

Answer 16

indigestible: can’t be broken down by enzymes
- send to colon
- softens stool
- slows digestion of glucose

Question 17

what is glycogen

Answer 17

storage form of CHO in the liver and muscles in humans and animals

Question 18

what are the two types of fibre?

Answer 18

soluble (viscous)
insoluble (non-viscous)

Question 19

what is soluble fibre?

Answer 19

-dissolves in water
- add thickness to food
- helps stool formation
- helps regulate blood glucose
- forms gel

Question 20

what is butyrate

Answer 20

• bacterial fermentation of soluble fibres produces small fat-like molecules such as butyrate
• butyrate provides energy to colon cells and improves microbiota

Question 21

what is insoluble fibre?

Answer 21

• do not dissolve in water
• helps move stool through the large intestine
• do not form gel

Question 22

what are 5 benefits of fibre?

Answer 22

1. lower blood cholesterol
2. blood glucose control
3. healthy weight management
4. lower rates of colon cancer
5. maintenance of gut health

Question 23

what are the two ways fibre lowers blood cholesterol, and how

Answer 23

1. vacuum-like action: foods rich in soluble fibres bind with cholesterol-containing bile in the intestine and then are carried out in faces
2. prevention: bacterial fermentation of fibre releases short-chain fatty acids (e.g butyrate) that help reduce cholesterol synthesis in liver

Question 24

how does fibre help blood glucose control?

Answer 24

• reduced risk of diabetes
• glucose absorption slowed down when fibre traps nutrients and delays transit
• prevents surges in blood glucose, less insulin release, improves insulin sensitivity over time

Question 25

how does fibre help healthy weight management?

Answer 25

- foods rich in complex CHO are often low in fats and added sugars - promote feeling of fullness and satiety

Question 26

how does fibre lower rates of colon cancer?

Answer 26

- assumed that it's related to the fermentation of short-chain fatty acids that have anti-carcinogenic properties by speeding the removal of harmful carcinogenic agents

Question 27

how does fibre maintain gut health?

Answer 27

- cellulose enlarges and softens the stool to help prevent constipation

Question 28

how does fibre prevent hemorrhoids?

Answer 28

- less likely to occur when stools are soft and pass through easily

Question 29

how does fibre prevent appendicitis?

Answer 29

prevented intestinal contents from moving through and not permitting bacterial growth

Question 30

how does fibre prevent diverticula

Answer 30

fibre stimulates GIT muscles to retain their strength

Question 31

where does digestion start and what is it initiated by?

Answer 31

digestion starts in the mouth and is initiated by salivary amylase

Question 32

what happens to starch in the mouth

Answer 32

split starch into maltose

Question 33

what happens in the small intestine?

Answer 33

- the majority of CHO digestion occurs here - pancreatic amylase: digestion of starch into shorter glucose chains and maltose - The outer membrane of intestinal cells secrete enzymes: lactase, sucrase, maltase - fibre is not digested here

Question 34

what happens in the large intestine?

Answer 34

- fibre and resistant starch travel unchanged to the colon - fibre attracts water to soften stool - bacterial fermentation may occur and odorous gases may be produced

Question 35

what is absorption

Answer 35

- occurs in the small intestine - enter cells (glucose/galactose) of the lining of the intestine via active transport - may also be absorbed via facilitated transport

Question 36

what does the liver do with galactose and fructose?

Answer 36

converts galactose and fructose to glucose

Question 37

what is glucose regulated by?

Answer 37

regulated by the pancreas via insulin and glucagon (hormones)