Carbohydrates

Question 1

What are simple carbohydrates?

Answer 1

Sugars composed of a single sugar molecule (a monosaccharide) or two joined sugar molecules (a disaccharide)

Simple carbohydrates are the most basic form of carbohydrates.

Question 2

Define monosaccharides.

Answer 2

Sugars that are not broken down further during digestion with the general formula CnH2nO, where n = 3 to 7

Common monosaccharides include glucose, fructose, and galactose.

Question 3

What are disaccharides?

Answer 3

Carbohydrates composed of two monosaccharide units linked by a glycosidic bond

Examples include sucrose, lactose, and maltose.

Question 4

What is glucose?

Answer 4

A common monosaccharide containing six carbons, also known as dextrose or blood sugar

It is a component of sucrose, lactose, and maltose.

Question 5

What is fructose?

Answer 5

A common monosaccharide containing six carbons, naturally present in honey and many fruits

Also referred to as levulose or fruit sugar.

Question 6

What is galactose?

Answer 6

A monosaccharide containing six carbons that can be converted into glucose in the body

It usually joins with other monosaccharides in foods and living systems.

Question 7

What are pentoses?

Answer 7

Sugar molecules containing five carbon atoms.

Question 8

What are sugar alcohols?

Answer 8

Compounds formed from monosaccharides by replacing a hydrogen atom with a hydroxyl group (–OH)

Commonly used as nutritive sweeteners, also called polyols.

Question 9

Define condensation in chemistry.

Answer 9

A reaction in which a covalent bond is formed between two molecules by removal of a water molecule.

Question 10

What is sucrose?

Answer 10

A disaccharide composed of one molecule of glucose and one molecule of fructose

Commonly known as table sugar.

Question 11

What is lactose?

Answer 11

A disaccharide composed of glucose and galactose, also known as milk sugar.

Question 12

What is maltose?

Answer 12

A disaccharide composed of two glucose molecules, sometimes called malt sugar

Maltose is formed whenever long molecules of starch break down.

Question 13

Define complex carbohydrates.

Answer 13

Chains of more than two monosaccharides, which may be oligosaccharides or polysaccharides.

Question 14

What are oligosaccharides?

Answer 14

Short carbohydrate chains composed of 3 to 10 sugar molecules.

Question 15

What are prebiotics?

Answer 15

Group of compounds that promote growth and activity of beneficial bacteria in the host organism.

Question 16

Define microbiota.

Answer 16

Community of beneficial and pathogenic microorganisms that inhabit the body.

Question 17

What are polysaccharides?

Answer 17

Long carbohydrate chains composed of more than 10 sugar molecules

They can be straight or branched.

Question 18

What is starch?

Answer 18

The major storage form of carbohydrate in plants, composed of long chains of glucose molecules.

Question 19

Define amylose.

Answer 19

A straight-chain polysaccharide composed of glucose units.

Question 20

What is amylopectin?

Answer 20

A branched-chain polysaccharide composed of glucose units.

Question 21

What is resistant starch?

Answer 21

A starch that is not digested.

Question 22

Define glycogen.

Answer 22

A highly branched polysaccharide composed of multiple glucose units, the primary storage form of glucose in animals.

Question 23

What is dietary fibre?

Answer 23

Carbohydrates and lignins that are non-digestible and not absorbed in the human small intestine.

Question 24

What is functional fibre?

Answer 24

Isolated non-digestible carbohydrates with beneficial effects in humans.

Question 25

Define total fibre.

Answer 25

The sum of dietary fibre and functional fibre.

Question 26

What is soluble fibre?

Answer 26

Non-digestible carbohydrates that dissolve in water.

Question 27

What is insoluble fibre?

Answer 27

Non-digestible carbohydrates that do not dissolve in water.

Question 28

Define cellulose.

Answer 28

A straight-chain polysaccharide composed of hundreds of glucose units linked by beta bonds ## Footnote It is non-digestible by humans and a component of dietary fibre.

Question 29

What are hemicelluloses?

Answer 29

A group of large polysaccharides in dietary fibre that are fermented more easily than cellulose.

Question 30

What are pectins?

Answer 30

Type of dietary fibre found in fruits.

Question 31

What are gums?

Answer 31

Dietary fibres found between plant cell walls and contain galactose and other monosaccharides.

Question 32

What are mucilages?

Answer 32

Gelatinous soluble fibres found in seaweed.

Question 33

What is psyllium?

Answer 33

The dried husk of the psyllium seed.

Question 34

Define lignins.

Answer 34

Insoluble fibres composed of multi-ring alcohol units, the only noncarbohydrate component of dietary fibre.

Question 35

What are β-glucans?

Answer 35

Functional fibre consisting of branched polysaccharide chains of glucose, helping lower blood cholesterol levels.

Question 36

What is chitin?

Answer 36

A long-chain structural polysaccharide of slightly modified glucose found in the hard exterior skeletons of insects and fungi.

Question 37

What is chitosan?

Answer 37

Polysaccharide derived from chitin.

Question 38

What is pancreatic amylase?

Answer 38

Starch-digesting enzyme secreted by the pancreas.

Question 39

True or False: Alpha (α) bonds can be broken by human intestinal enzymes.

Answer 39

True.

Question 40

True or False: Beta (β) bonds can be broken by human intestinal enzymes.

Answer 40

False.

Question 41

Where does carbohydrate digestion primarily take place?

Answer 41

In the small intestine.

Question 42

What are ketone bodies?

Answer 42

Molecules formed when insufficient carbohydrate is available to completely metabolise fat.

Question 43

Define ketosis.

Answer 43

Abnormally high concentration of ketone bodies in body tissues and fluids.

Question 44

What is the function of insulin?

Answer 44

Stimulates the uptake of blood glucose into muscle and adipose cells and the synthesis of glycogen in the liver.

Question 45

What does glucagon do?

Answer 45

Promotes the breakdown of liver glycogen to glucose, increasing blood glucose levels.

Question 46

What is the glycemic index?

Answer 46

A measure of the effect of food on blood glucose levels.

Question 47

What is diabetes mellitus?

Answer 47

A chronic disease in which uptake of blood glucose by body cells is impaired, resulting in high glucose levels in the blood and urine.