Proteins

Question 1

What are proteins

Answer 1

Molecules that can be found in all living cells and within the human body

Question 2

How much of our body do they make up

Answer 2

One sixth of our body weight

Question 3

Proteins are the major what

Answer 3

Major structural component of animal tissue and give shape to our bodies forming our hair, nails and along with water and the major substances that make up our muscles organs, blood & skin

Question 4

What are proteins also responsible for

Answer 4

Forming collagen of the connective tissue that holds out bones together and they wrap out bodies in flesh

Question 5

Proteins are also vital for what

Answer 5

Repairing and regulating bodily processes

Question 6

Examples for repairing and regulating body processes

Answer 6

•Enzymes (catalysing chemical reactions)

•Hormones (insulin)

•Haemoglobin (oxygen carrying)

Question 7

Amino acids

Answer 7

Molecules that join together to form protein molecules

Question 8

How many amino acids are there?

Answer 8

Around 20 different amino acids used to synthesis proteins which can all be represented by the following general structure

Question 9

Amino acids have 2 functional groups attached to the same carbon atom

Answer 9

An amino group (-NH2)

And a carboxylic group (-COOH)

Question 10

Amino acids differ in the side chain that is

Answer 10

Attached to the carbon

Question 11

Essential amino acids are

Answer 11

Amino acids that animals cannot synthesis for themselves. About half the amino acids we need are essential amino acids

Question 12

Plants on the other hand are able to

Answer 12

Synthesis all of the amino acids needed to make proteins

Question 13

Animals including human obtain these amino acids by

Answer 13

Hydrolysing the plants they eat

Question 14

During digestion these proteins are hydrolysed and pass into our bloodstream to be

Answer 14

Carried to the various parts of our body were they are needed

Question 15

Proteins are made by joining together amino acids in a

Answer 15

Condensation reaction

Question 16

What allows them to be condense togther and form larger molecules

Answer 16

The 2 functional groups

Question 17

Whats the group that links the amino acids together called

Answer 17

An amid link

Question 18

What is an amid link called when present in a peptide

Answer 18

Peptide link

Question 19

Proteins are polypeptides and range in length from 40 amino acid

Answer 19

Units to over 400 amino acid units

Question 20

In these condensation reactions what does the amino acid group do

Answer 20

The amino acid group from one amino acid joins togther with the carboxylic group from another amino acid forming an amid or peptide link eliminating water in the process

Question 21

When amino acids are join together a molecule known as a

Answer 21

Peptide is formed

Question 22

Two amino acids joined together as known as

Answer 22

A dipetide

Question 23

Three amino acids joined are

Answer 23

Triptide

Question 24

When a large number of amino acids join together the molecule know is

Answer 24

Polypeptide

Question 25

Proteins present in our diets need to be broken down so our bodies can

Answer 25

Process them

Question 26

How is this done

Answer 26

It’s done during the digestion process where the proteins react with water molecules and undergo a hydrolysis reaction which is catalysed by enzymes

Question 27

In the hydrolysis reaction water molecules attack and break

Answer 27

The C-N bonds of the peptide links generating the individual amino acids molecules

Question 29

In a lab how is protien hydrolysed back to its constituent amino acids?

Answer 29

By refluxing with concentrated hydrochloric acid for many housv

Question 30

How can amino acids be identified

Answer 30

By the use of chromatography paper

Question 31

A piece of chromatography paper is spotted with some amino acids that are

Answer 31

Suspected as being present and also with the hydrolysed protein

Question 32

By comparing the position of the spots of the know amino acids with that of the hydrolysed protein

Answer 32

The amino acids with that of the hydrolysed protein, the amino acids in the protein can be identified

Question 33

Protein molecules contain polar peptide links which can form

Answer 33

Hydrogen bonds with others in the same chain reaction to form a spiral

Question 34

These spirals can be formed into what

Answer 34

More complicated structures classified as globular or fibrous

Question 35

Fibrorous proteins consist of interwoven chains forming a

Answer 35

Rope like structure

Question 36

In addition to the hydrogen bonds in the chain

Answer 36

The hydrogen bonds also operate between the chains

Question 37

When these proteins are heated tye hydrogen bonds are broken

Answer 37

Which causes the protein chain to unravel

Question 38

Globular proteins have irregular shapes due to

Answer 38

The protein chains colling and twisting

Question 39

When heated the hydrogen bonds that hold the protein in its globular shape break the protein uncoils forming

Answer 39

New hydrogen bonds

Question 40

In general when a protein is heated

Answer 40

IMF break down, and the shape of the protein shape is irreversibly changed

Question 41

The proteins is said to denature. The denaturing of food causes the

Answer 41

Texture to changed when it’s cooked

Question 42

Enzymes are

Answer 42

Biological catalyst

Question 43

What are enzymes like

Answer 43

Specific to a particular chemical reaction

Question 44

What do certain sequences of amino acids form

Answer 44

A region called the active site

Question 45

What does the shape of the active site allow

Answer 45

Specific reactants known as substrate to attach, like a lock and key

Question 46

Incorrect substances are unable to

Answer 46

Fit the substrate shape of the active site and aren’t changed

Question 47

Enzyme function is there for not related to

Answer 47

Molecular shape of proteins