Download Protein structure - Manning`s Science

Answer all questions fully in your exercise books
1)What causes the colour change seen in the
reducing sugars test?
2)Why is vitamin K2 important and how is it
obtained?
3)What bond is formed when monosaccharide's
join?
4)What is an isomer?
5)What does a semi-quantitative result mean?
6)Why do people with diabetes have slow
healing of wounds?
7)What is glycemic response
AS Human Biology:
Unit 1 Biology & Disease
In pairs write down everything you can about proteins.
STUCK?
Think about:
How they are made,
Where they are used,
Why we need them,
And anything else you can.
The basic units



A protein is a special
type of polymer called
a POLYPEPTIDE.
The monomers that
join together to make
the polymer are the
amino acids.
Proteins are known as
polypeptides because
the bonds that join the
amino acids together
are called PEPTIDE
bonds.
One Man or A monomer
Lots of Men or a Polymer
Amino Acid Structure
Every Amino Acid has
a central carbon and
 An amino group
( NH2)
 A Carboxyl Group
( COOH)
 A hydrogen atom
( H)
 An R Group –
chemical group
different to each
amino acid
Polypeptides

A polypeptide is a chain of amino acids.

Amino acids are covalently linked by peptide bonds.

Each polypeptide can be made from a variety of
different amino acids

Every polypeptide has a free amino end and a free
carboxyl end.
The formation
of a peptide
bond
In this CONDENSATION
reaction one hydrogen
from the amino group
joins with the OH from the
carboxyl group. This
forms a water molecule.
The Nitrogen atom them
combines with the carbon
atom forming a peptide
bond.
The PEPTIDE bond between
the C of the 1st amino acid
and the N of the second
amino acid creates a new
molecule.
As there are now two amino
acids joined together we
have a DIPEPTIDE. “Di”
meaning two.
More amino acids joining on
in the same way would make
the POLYPEPTIDE chain.
The whole process is called
POLYMERISATION.
A HYDROLYSIS Reaction


A hydrolysis reaction
is the reverse. A
polypeptide can be
split up by the
addition of a water
molecule.
This can also
happen to a
dipeptide giving us
back the two amino
acids molecules we
began with.
What type of bond links amino acids together?
2. What is the reaction which links amino acids
together called?
3. What are the four main components of a basic
amino acid?
4. What is specific about the “R” group?
5. Where do you obtain amino acids from?
6. Where can amino acids be made within the body?
7. Which two atoms bond together in polypeptide?
8. What is the difference between a dipeptide and a
polypeptide?
9. What is a hydrolysis reaction?
10. What is a protein?
1.
A peptide bond
2. Condensation reaction
3. Carboxyl group, amino group, hydrogen and the r
group
4. It is different for every amino acid
5. Diet, meat, fish and pulses.
6. Liver by transamination
7. Nitrogen and Carbon
8. A “di” contains only two and a “poly” contains
more than two
9. Where molecules are split up by the addition of
water.
10. A polymer made from amino acids
1.