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Lab: Proteins
Biology
A. Introduction:
1. List 3 foods that have protein
a.
b.
c.
2. List 3 ways that proteins are used in your body
a.
b.
c.
B. Amino Acids – The Building Blocks of Proteins
1. What are the common elements found in amino acids?
(Refer to the model sheet)
2. An amino acid has a central carbon which always has the
following 3 groups always attached: (Refer to p. 101 in text)
Group Name
Formula
3. The central carbon atom also has a side group which is
different in every amino acid. What is the side group of:
a. leucine –
b. serine –
c. valine –
d. theronine (Show formula of side group)
4. How many different amino acids are there to build
proteins?
B. Constructing a Protein
1. Cut out 2 of the amino acid models
2. Remove an “OH” from one model, then remove an “H”
from the other model.
3. Do NOT throw these groups away
4. EQUATION WRITING(Use the white drawing paper)
a. Write the names of the reactants to the left side of
the drawing paper. Place a plus sign between the
names.
b. Draw an arrow following the reactant names
toward the right of your paper
c. Glue the amino acids together so that they fit like
pieces of a puzzle. Place a name beneath the model.
d. Follow the model with a plus sign.
e. Glue the “OH” and the “H” groups together to
form a new compound. Bond the “OH” and “H”
together. Name the new compound below the
model.
5. Place an appropriate title on your drawing paper
6. Is the reaction an example of hydrolysis or dehydration?
Explain:
7. The protein that you just made is an example of a
dipeptide. Now, use 3 of your amino acids to form a
tripeptide. Follow the same basic instructions as you
did to make the dipeptide. Complete an equation on
your drawing paper.
8. Explain how 2 different proteins could be made from the
same 3 amino acids.
9. Proteins usually consist of a long chain of amino acids.
The chain is ____________, _____________, or
___________ into a unique shape(refer to page 102 of
your textbook). This unique shape enables the protein to
function correctly.
10.Sometimes proteins lose their shape due to various
reasons. What is the process called when proteins lose
there shape?
11.What can happen to a protein that would lose its shape?
a.
b.
c.
12.You have models of a dipeptide and a tripeptide. If you
were assigned a polypeptide to construct, how many
amino acids could you use?
SUMMARY
1. What are the building blocks of all proteins?
2. There are thousands of different types of proteins, but
there are only _______ monomers that are used to
build proteins. How can thousands of different
proteins be made from just a few building blocks?
3. What other product is made in addition to the
protein?
4. Building proteins from monomers is an example of
what type of chemical reaction?(hydrolysis or
dehydration)