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Flashcards in Biomolecules Deck (119)
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1

What is the biological test for starch?

1. Add a few drops of iodine solution
2. Record any colour change

2

What is the colour change for the biological starch test?

Yellow to Dark Blue/ Black (for a positive result)

3

What is the biological test for reducing sugars?

1. Add 2cm' of Benedict's reagent to the solution
2. Place in a 90° - 100° water bath for 5 mins.
3. Record any colour change

4

What is the colour change for the biological test for reducing sugar?

Blue to Red (for a positive result)

5

What is the biological test for non-reducing sugars?

1. Add 1cm' of 1M of hydrochloric acid to solution
2. Place in a 90°-100° water bath for 2 mins
3. Neutralise with sodium hydrogen carbonate
4. Add 2cm' of Benedict's reagent
5. Place in a 90°- 100° water bath for 5 mins
6. Record any colour change

6

What is the colour change for the biological test for non-reducing sugar?

Blue to Red (for a positive result)

7

What is the biological test for a protein?

1. Add 2cm' of 0.4M sodium hydroxide to solution
2. Add 0.4M copper (II) sulphate drop by drop
3. Shake gently and record results

8

What is the colour change for the biological for a protein?

Blue to Purple (for a positive result)

9

What is the biological test for a lipid?

1. Shake solution with absolute ethanol for 1 min
2. Add 2cm' of water and shake well
3. Record observations

10

What is the colour change for the biological for a lipid?

Clear to a milky solution (for a positive result)

11

What are the three types of carbohydrates?

1. Monosaccharides
2. Disaccharides
3. Polysaccharides

12

Which two carbohydrates for crystals, are soluble, and ?

Monosaccharides and Disaccharides

13

What are the 4 functions of carbohydrates? (In humans and plants)

1. Instant energy source
2. Transportable form of energy
3. Stored as glucose
4. Structural material ( in plants)

14

What is the formula for Glucose?

C6H12O6

15

What is the definition of a disaccharide?

Two monomers joined together by a condensation reaction

16

What is the definition of a condensation reaction?

A reaction between two hydroxyl groups where water is lost and a glycosidic bond is formed.

17

What type of bond is C-O-C?

A glycosidic bond

18

What is made from Glucose + Glucose?

Maltose

19

What is made from Glucose + Galactose?

Lactose

20

What is made from Glucose + Fructose?

Sucrose

21

What is the definition of a hydrolysis reaction?

Splitting a glycosidic bond using a molecule of water

22

What is the general formula of a monosaccharide?

C(H2O)n

23

What is a ring with 6 carbon atoms called?

A Hexose

24

Why is glucose a suitable sugar? (4 reasons)

1. Its very soluble so its easily transported in plasma
2. A polar molecule (uneven charge within the molecule)
3. Small so easily crosses membranes
4. Major respiratory substrate is readily broken down in respiration and energy release to make ATP

25

Why is chitin good for animal/insects' exoskeleten?

1. Its waterproof which prevents water loss
2.Its strong for support
3.Its light weight for flight

26

What is the structure of Glycogen? (3 points)

.Alpha glucose
.More Branched
.1-4 and 1-6 glycosidic bonds

27

What is the function of starch?

Storage in plants

28

What are the two types of starch?

Amylose and Amylopectin

29

What is the structure of amylose?

Straight chain

30

What is the structure of amylopectin?

Curved/ Coiled chain