2.2 Carbohydrates Flashcards Preview

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Flashcards in 2.2 Carbohydrates Deck (38)
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1
Q

why do we need carbohydrates?

A

for energy

2
Q

what are carbohydrates made up of?

A

hydrogen, oxygen and carbon

3
Q

what type of compounds are carbohydrates?

A

organic compounds

4
Q

what are the three types of carbohydrate?

A

monosaccharides, disaccharides and polysaccharides

5
Q

what are the three types of monosaccharides?

A

glucose, fructose and galactose

6
Q

what type of monosaccharide is glucose?

A

a hexose monosaccharide

7
Q

what are monosaccharides?

A

the simplest single sugars

8
Q

what happens when monosaccharides react with water?

A

they dissolve to form sweet tasting solutions

9
Q

what are alpha glucose and beta glucose?

A

isomers

10
Q

what type of monosaccharide is ribose?

A

a pentose monosaccharide

11
Q

where is deoxyribose found?

A

DNA

12
Q

where is ribose found?

A

RNA

13
Q

what is formed when two monosaccharides join?

A

a disaccharide

14
Q

what bond is formed when two monosaccharides join to form a disaccharide?

A

a glycosidic bond, for example when two glucose join to form maltose this is a 1-4 glycosidic bond as carbon 1 is bonded to carbon 4

15
Q

What reaction occurs when a monosaccharide forms a disaccharide?

A

A condensation reaction, H2O is lost and as a result water is formed as a product

16
Q

What happens to a disaccharide to go back to monosaccharides?

A

They hydrolyse (water is added)

17
Q

What is a polysaccharide formed from?

A

Many monosaccharides

18
Q

What are three types of polysaccharide?

A

Starch, glycogen and cellulose

19
Q

What is starch used for?

A

It is the main storage polysaccharide in plants

20
Q

What type of glucose is starch made of?

A

Alpha glucose

21
Q

What are the two polymers of alpha glucose?

A

Amylose and amylopectin

22
Q

What is the structure of amylose?

A

chain of glucose molecules, form a helix structure by hydrogen bonding

23
Q

What is the function of the structure of amylose?

A

helix forms a compact shape good for packaging making it a good storage molecule

24
Q

What is the structure of amylopectin?

A

Chains of glucose molecules, after every 25 glucose molecules adjacent chains are connected by alpha 1-6 glycosidic bonds, giving it a BRANCHED STRUCTURE

25
Q

What is the function of the structure of amylopectin?

A

The branched ends can be hydrolysed rapidly allowing the rapid release of glucose for energy

26
Q

What makes starch a good storage polysaccharide?

A

It is insoluble in water

27
Q

What is glycogen used for?

A

It is the main storage polysaccharide of animal and fungi cells

28
Q

What is the structure of glycogen?

A

Similar to amylopectin, but it has more branches which are shorter, making it more compact

29
Q

What is the function of the structure of glycogen?

A

can be quickly broken down to release glucose for energy

structure allows faster hydrolysis important as animals may need emergency glucose faster than plants

30
Q

What is cellulose used for?

A

It is the structural polysaccharide in plants

31
Q

What is the structure of cellulose?

A

Long unbranched chains of glucose, linked to each other by hydrogen bonds, which are formed into strong microfibrils

32
Q

What bonds are the glucose chains in cellulose linked by?

A

Beta 1-4 glycosidic bonds

33
Q

What type of glucose is cellulose made of?

A

Beta glucose

34
Q

What is the function of the structure of cellulose?

A

Hydrogen bonding prevents water entering the molecule making it resistant to enzyme hydrolysis, makes it a good structural polysaccharide.
Cellulose in plant cell walls provides protection

35
Q

What are the three types of disaccharide?

A

Maltose, sucrose and lactose

36
Q

What is maltose the product of?

A

Glucose + Glucose

37
Q

What is sucrose the product of?

A

Fructose + Glucose

38
Q

What is lactose the product of?

A

Galactose + Glucose

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