Biological Molecules

Question 1

Definition of a monomer

Answer 1

Smaller repeating units; building blocks of polymers

Question 2

Macromolecules are:

Answer 2

large molecules with 3D structures and functions

Like proteins

Question 3

Monomers of proteins are:

Answer 3

Amino acids

Question 4

An amino acid is made up of:

Four things to mention

Answer 4

• An amine group -NH4
• A central carbon
• An ‘R’ group
• A carboxyl group -COOH

Question 5

A dipeptide is made up of what with what bond?

Answer 5

• Two amino acids
• A peptide bond

Question 6

Polypeptide are

Answer 6

Dipeptides joined together by a peptide bond

Question 7

Polypeptide are

Answer 7

Dipeptides joined together by a peptide bond

Question 8

What is the variable ‘R’ group?

Answer 8

It’s the part of the amino acid that determines how the amino acid will interact in the environment and with other amino acids

Question 9

Amino acids are linked together with what reaction to form what bond?

Answer 9

• Condensation reaction
• Peptide bond

Question 10

How many amino acids are there? How many are essential?

Answer 10

• 20 amino acids
• 9 essential

Question 11

How many stages of folding can a protein go through?

Answer 11

Four

Primary, secondary, tertiary and quaternary

Question 12

What happens in the primary structure?

Answer 12

The amino acids bond together with a peptide bond to form a polypeptide chain

Question 13

What happens in the secondary structure?

Answer 13

Hydrogen bonds form between neaby amino acids between the amine and the carboxyl groups within the chain

This folds the chain

Question 14

What happens in the tertiary structure?

Answer 14

More bonds occur such as:
- Disulphide bonds
- Ionic bonds
- More hydrogen bonds
- Polar interactions

This further folds the chain into a 3D shape

Question 14

What happens in the tertiary structure?

Answer 14

More bonds occur such as:
- Disulphide bonds
- Ionic bonds
- More hydrogen bonds
- Polar interactions

This further folds the chain into a 3D shape

Question 15

What happens in th quaternary structure?

Answer 15

Multiple polypeptide chains are bonded together to form something much more advanced and specific

Not all proteins have to have a quaternary structure

Question 16

What are the two types of proteins?

Answer 16

Globular and Fibrous

Question 17

What is the most abundant molecule?

Answer 17

Carbohydrates

Question 18

Monomers of polysaccharides are?

Answer 18

Monosaccharides

Question 19

Monosaccharides are bonded together through what reaction with which bond?

Answer 19

• Condensation reaction
• Glycosidic bond

Question 20

The monomers for sucrose are?

Answer 20

Glucose and fructose

Question 21

The monomers for lactose are?

Answer 21

Glucose and galactose

Question 22

Monomers for maltose are?

Answer 22

Glucose and Glucose

Glucose is classified as a monosaccharide

Question 23

Two isomers of glucose are?

Isomers are compounds with the same formula but different arrangement

Answer 23

A-glucose
B-glucose

Question 24

How is a-glucose structured?

Answer 24

As a coil

Question 25

How is b-glucose structured?

Answer 25

Like a zigzag

Question 26

Why are carbon-containing molecules classed as organic molecules?

Answer 26

They easily bond with eachother and create a strong backbone for other molecules to add on

Question 27

Test for proteins and result?

Answer 27

* Biuret test * Blue to violet

Question 28

Test for reducing sugars and result? | All monosaccharides and some disaccharides are reducing sugars

Answer 28

- Benedict's test - Blue to brick red

Question 29

Test for polysaccharides and result? | Basically the Benedict's test with extra steps ## Footnote Polysaccharides aren't reducing sugars, so we have to break them down into them for the test to work

Answer 29

1. Put small amount of sample in test tube 2. Add HCL and boil for 1 minute- to hydrolyse(split up the saccharide) 3. Add sodium hydrogen carbonate (to neutralise) 4. Put into water bath for 5 minutes 5. Positive test = brick red solution

Question 30

Why is glucose stored as glycogen in humans?

Answer 30

- Glucose is very reactive on its own - can interfere in reactions - Will also affect water potential

Question 31

How is glucose stored in humans and plants?

Answer 31

- Glucagon in humans - Starch in plants

Question 32

Lipids aren't solube in water but are soluble in?

Answer 32

organic ssolutions such as acetone or alcohols

Question 33

Can lipids dissolve in water?

Answer 33

No - they are hydrophobic

Question 34

What is a fatty acid?

Answer 34

A chain of 4-24 hydrocarbons and a carboxyl group

Question 35

Lipids are held together using what bonds?

Answer 35

Ester bonds

Question 36

What do catabolic reactions do?

Answer 36

Break larger molecules into smaller ones

Question 37

What do anabolic reactions do?

Answer 37

Build larger molecules from smaller ones

Question 38

Monomers of lipids

Answer 38

Fatty acids and glycerol | Found most commonly in the form of triglycerides