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Flashcards in 1A Biological Molecules Deck (50):
1

What are carbohydrates made from?

Monosaccharides such as glucose, fructose and galactose

2

Carbohydrate condensation reaction products?

(Glycosidic Bond ) and water released

3

Examples of carbohydrate condensation reactions

Glucose + fructose -> sucrose

Glucose + galactose -> lactose

2 monosaccharides-> disaccharide

4

Alpha vs Beta glucose

H
OH



OH
H

5

Hydrolysis reaction in carbohydrates

Break glycosidic bond by adding water

Polymers into monomers

6

Reducing sugars test

Heat with Benedicts
Turns brick red



B-r

7

Non reducing sugars test

Add dilute hcl
Heat
Neutralise with sodium hydrogen carbonate
Heat with Benedicts
Turns brick red


B- r

8

Starch test

Add iodine dissolved in potassium iodide solution


Borneo orange - blues black

9

What is formed when 2 monosaccharides join by a condensation reaction?

Polysaccharides

10

Purpose of starch in plants

- main energy store in plants
- stores excess glucose so when the plant is low the stored starch can get to the glucose . Starch is a mixture of 2 alpha glucose polysaccharides - amylose and amylopectin

11

Amylose

Long unbranched coiled and compact alpha helix

12

Amylopectin

Long unbranched side branches allow enzymes to get at glycosidic bonds easier so glucose can be released quicker

13

Advantages of starch being insoluble

Doesn’t affect WO so doesn’t cause water to enter by osmosis which would make them swell- so good for storage

14

Purpose of glycogen in animal cells

(Main energy store in animals)
-stores excess glucose as glycogen ( alpha)


-similar structure to amylopectin except it has more branches so stored glucose can be released more quickly
- compact - good for storage
- rapid hydrolysis

15

Cellulose

Long unbranched chains of beta glucose

Bonded molecules of B forms straight chains

Cellulose chains linked together by hydrogen bonds to form strong fibres called microfibrils

- strong fibres mean cellulose provides structural support for cells

16

What is a triglycerides

A lipid

17

Structure of a triglyceride



G
L —fatty acid
Y
C
E — fatty acid
R
O — fatty acid
L

18

What’s a fatty acid

Hydrocarbon chain - hydrophobic so insoluble in water

19

How is a triglyceride formed

Condensation reaction when 3 fatty acids join to a glycerol when water is released


Ester bonds

20

Saturated HC

NO double bonds between carbon atoms in the HC chain

21

Unsaturated HC

At least ONE double bond between carbon atoms in the HC chain

22

Phospholipid

Similar to triglyceride




G
L —- fatty acid
Y
C
E —- fatty acid
R
O
Phosphate —— L
Group

23

Phospholipid description

Found in cell membranes

Fatty acid replaced by phosphate group

Phosphate group is hydrophilic ( attracts water)

Tails are hydrophobic repel water

24

Triglycerides functions

Energy store molecules


1. Long HC tails contain lots of energy which is released when they’ve broken down

2. Insoluble - doesn’t affect WP and cause water to enter the cell by osmosis making them swell- clump together as insolvable droplets in cells are hydrophobic so face I waters shielding from water with glycerol heads

25

Phospholipid function

- make up bilateral of cell membranes
- hydrophilic heads and hydrophobic tails- forming a double layer
- centre is hydrophobic so water soluble substances can’t pass through easily

26

Emulsion test for lipids

- Shake with ethanol
- pour into water

-> milky emulsion

27

Proteins are made from long gains of amino acids

Monomers = amino acids

Two amino acids joining together = dipeptide

Polypeptide = more than two amino acids

Proteins = more than one polypeptide

28

Amino acid


R
|
H2N—C—COOH
|
H




20 amino acids

29

Polypeptide bonds formation

Formed by condensation reactions of amino acids


- water released
- peptide bond formed

30

Primary structure

Sequence of amino acids in the polypeptide chains

31

Secondary Structure

Polypeptide chain doesn’t remain flat and straight
- hydrogen bonds form between amino acids in the chain
- coils in a helix
Or
- fold into b pleated sheet

32

Tertiary structure

Coiled and folded further .
- more bonds form:
- hydrogen
-ionic bonds
- disulphides bridges

- final 3D structure

33

Quaternary Structure

- made of several different polypeptide chains held together by bonds
- it’s the way they are assembled together

- final 3D Structure

34

Protein functions

1. Enzymes - spherical due to tight folding of the polypeptide chains. Soluble. Metabolise and synthesise.

2. Antibodies - are involved in the immune response - 2 light and 2 heavy polypeptide chains. Variable regions.

3. Transport proteins - channel proteins

4. Structural proteins - strong - long polypeptide chains lying parallel with cross links - keratin and collagen

35

Biuret test for proteins

Add sodium hydroxide
Add copper surface solution

Protein = purple
No protein = blue

36

Enzymes

-Catalysts
- can affect structures in an organism
- can be intracellular
- are proteins
- have an active site
- highly specific due to tertiary structure

37

Activation energy

Amount of energy that needs to be supplied to the chemicals before the reaction will start

38

Enzymes lowering AE

- make the reaction happen at a lower temp => speeds up ROR

....

39

Lock and key

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40

Induced fit

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Enzymes and tertiary structure

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42

Temp and enzymes

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43

pH and enzymes

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44

Conc and enzymes

...

45

Substrate conc and enzyme

...

46

Competetive inhibition


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Non competitive inhibition

...

48

Enzyme controlled reactions

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