1A - biological molecules Flashcards Preview

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Flashcards in 1A - biological molecules Deck (21)
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1
Q

what are polymers?

A

large, complex molecules composed of long chains of monomers joined together.

2
Q

what are monomers?

A

small, basic molecular units that form a polymer.

3
Q

what are some examples of monomers?

A

monosaccharides, amino acids and nucleotides.

4
Q

how are polymers formed?

A

condensation reactions between two or more monomers.

5
Q

what is a condensation reaction?

A

a reaction that forms a chemical bond between monomers, releasing a molecule of water.

6
Q

how can you break down polymers?

A

hydrolysis reaction.

7
Q

what is a hydrolysis reaction?

A

a reaction that breaks down the chemical bond between monomers using a water molecule.

8
Q

what are monosaccharides?

A

monomers of carbohydrates.

9
Q

give three examples of monosaccharides.

A

glucose, fructose and galactose.

10
Q

what type of sugar is glucose?

A

hexose sugar (a monosaccharide with six carbon atoms in each molecule).

11
Q

what are the two types of glucose?

A

alpha and beta.

12
Q

what are isomers?

A

molecules with the same molecular formula but with the atoms connected in a different way.

13
Q

what is a disaccharide?

A

where two monosaccharides join together.

14
Q

what bond is formed between two monosaccharides?

A

a glycosidic bond.

15
Q

give three examples of disaccharides.

A

maltose, lactose and sucrose.

16
Q

what test is used for finding reducing and non-sugars?

A

the benedicts test.

17
Q

how do you use the benedicts test for finding reducing sugars?

A

heat the sample with benedicts reagent. if the sample forms a green, yellow, orange or brick red precipitate then reducing sugar is present.

18
Q

what colour is benedicts reagent?

A

blue.

19
Q

how do you use the benedicts test to find non-reducing sugars?

A

if there’s no reducing sugar present, get a new sample and add dilute hydrochloride acid and then add sodium hydrogen carbonate to neutralise the solution. if the sample remains blue, no non-reducing sugar is present.

20
Q

what is a polysaccharide?

A

two or more monosaccharides joined together.

21
Q

give three examples of polysaccharides.

A

starch, glycogen and cellulose.