Amino acids are the basic monomers and building blocks of proteins (polymers). Their structure consists of three main groups as seen in Figure 1, namely the amino group or N terminus, carboxyl group or C terminus and the R group which contains the functional component of the amino acid. The R group gives the amino acid specific features according to its polarity and charge, which then affect the chemical and biological properties of the protein.
There are a total of 21 amino acid types based on their different R groups. 12 of these can be synthesized in the body, while the other 9 must be consumed in the diet, hence are termed essential amino acids.
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Required
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Question 2
2.
Label the diagram with the words in the word bank
Word Bank:
Amino group
R group (side chain)
Carboxyl group
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Question 3
3.
This is a monomer of a protein and is called...__________
Which portion of the amino acid gives the amino acid a specific feature like polarity or charge? __________
How many amino acids can our body's make? __________
According to the image, what main type of bond holds the amino acids in a protein together. __________
Required
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Question 4
4.
Proteins are _____________ . The monomers of proteins are called ________________
Other Answer Choices:
polymers
amino acids
fatty acids
Required
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Question 5
5.
YOU MUST USE THE SENTENCE STARTER:
I agree with __________, because from the diagram you can see...
According to the gif and the following students responses, how do amino acids bond together to make polymers (proteins)?
Silas - The carboxyl group becomes Hydrolyzed by the electrons leaving. Then the R group of the other amino acid gains an H2O. This allows a dimetric bond between two amino acids to occur, fusing the molecules to make a polymer.
Enoch - The Carboxyl group of one amino acid loses an OH, and the amino group of another amino acid loses an H. This allows the two amino acids to bond togther and make a polymer through dehydration synthesis.
Mclaine - The carboxyl group does a kickflip like Andrew Petersen straight into the diabolically whole we called primitive life. Film a video and sip on it, yoh.
Required
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Question 6
6.
The order by which this polymer is made is that _______________ monomers bond together in peptide bonds to make _____________ and then peptides fold to make _____________ .
Other Answer Choices:
amino acid
Proteins
peptides
Required
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Protein structure can be divided into four main categories depending on level of complexity.
* Primary structure: Peptide bonds between amino acids form a straight chain of peptides called a polypeptide, the primary structure.
* Secondary Structure: Formation of hydrogen bonds between this initial structure leads to the formation of the secondary protein structure. Amino acid sequences will commonly fold into two stable configurations of secondary structures
Alpha helices occur when the amino acid sequence folds into a coil / spiral arrangement
Beta-pleated sheets occur when the amino acid sequence adopts a directionally-oriented staggered strand conformation
* Tertiary Structure: Folding of this polypeptide chain into a 3D shape forms the tertiary structure.
* Quarternary Structure: The combination of multiple different polypeptide chain leads to formation of the quaternary structure.
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Question 10
10.
The primary structure of a protein...__________
The secondary structure of a protein.. __________
The tertiary structure of a protein...__________
The quaternary structure of a protein...__________
Required
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Question 11
11.
Find and place the proper lables on the protein structures
Lables:
Primary
Secondary
Tertiary
Quarternary
Required
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Question 12
12.
Catergorize the following structures into their proper categories
Primary Structure
Secondary Structure
Tertiary Structure
Quarternary Structure
Required
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Question 13
13.
Look at the diagram and then read the following:
Certain proteins possess a fourth level of structural organisation called a quaternary structure. Quaternary structures are found in proteins that consist of more than one polypeptide chain linked together. Alternatively, proteins may have a quaternary structure if they include inorganic prosthetic groups as part of their structure. Not all proteins will have a quaternary structure – many proteins consist of a single polypeptide chain. An example of a protein with a quaternary structure is haemoglobin (O2 carrying molecule in red blood cells). Haemoglobin is composed of four polypeptide chains (two alpha chains and two beta chains). It is also composed of iron-containing haeme groups (prosthetic groups responsible for binding oxygen).
In your own words, what is the difference between a tertiary and quarternary protein?
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Question 14
14.
Word Bank:
peptide
more
help
synthesis
pH
helix
side
chain
hydrogen
diseases
water
reversible
denature
substrates
ideal
outside
vary
folding
influence
monomer
function
roles
We all have things that challenge us- and for me- it is folding. Sheets, towels, shirts- let’s just say I invest in a lot of anti-wrinkle laundry spray. It was the actual folding part that I tended to get stuck on. You may think of folding as a convenience- of a way to take something and make it more organized or condensed so it doesn’t have to take up as much space.This is true.
In biology, folding can also have a lot to do with _______. Proteins can play so many _______ . They can make up channels, be a part of structure, serve as enzymes for important biological processes, be involved with protecting the body...just to name a few. You are making proteins, all the time, in a process known as protein _______ . But the conclusion of producing a long chain of amino acids doesn’t necessarily equal a functional protein. There are modifications to a protein that often need to happen in order for it to be functional. By modifications, we can mean many things. It might be adding certain chemical groups, such as phosphorylation. But another important event to make a functional protein is---believe it or not---_______ . But before we get into protein folding, let’s talk about shape and why shape is so important.
Shape and function, in biology, frequently go hand in hand.
In cell signaling, protein receptors and the signal molecules that bind them can fit together so perfectly to start some type of cellular response. Enzymes---which are frequently proteins---have a very specific shape for the _______ that they build up or break down. When we talk about the way proteins are folded, we need to understand the different levels of protein structure because there are different ways of folding that can happen in the different structural levels.
The first level of protein structure is primary structure. This is the sequence of amino acids that make up a protein. Amino acids are the _______---which means the building block---of a protein. They are held together by _______ bonds. In protein synthesis, amino acids are added to form a polypeptide _______ and proteins are made of 1 or more of these polypeptide chains. Genes, which are made of DNA, determine the order and number of these amino acids. That sequence is critical to the protein’s structure and function.
In mutations, one amino acid can be changed in sickle cell disease. Even a single change of an amino acid has the potential to affect a protein’s function. We do want to point out- each amino acid has a carboxyl group, an amino group, and a R group- an R group is also called a _______ chain.
Folding is really going to start to happen in the secondary structure. In secondary structure, the sequence of amino acids that we mentioned in primary structure, can fold in different ways. The most common ways are the alpha _______ and the beta pleated sheet and which one of these foldings the protein does depends on the amino acid arrangement it has. Both of these shapes are due largely in part to _______ bonds. Those hydrogen bonds can occur at specific areas of the protein’s amino acids. Specifically, these are hydrogen bonds involving the backbone of the amino acid structure-we’re not focusing on the R groups right now.
On to tertiary structure. This is looking at more folding that occurs in the 3D shape of a functional protein. And a lot of this is due to something we haven’t mentioned much…the R groups. Also called side chains. See, the amino group and the carboxyl group are generally standard parts of an amino acid, although the R group found in amino acids can _______ among different amino acids. That means, the R group can define the amino acid and can make amino acid behave a certain way. For example, some R groups are hydrophilic. They like _______ . Some R groups are hydrophobic. They don’t. And remember that proteins contain many amino acids which can contain different R groups and so different areas of the protein can therefore be impacted based on those R groups. When protein folding is going on, amino acids with hydrophilic R groups may hang out on the _______ while hydrophobic R groups. Where are they? They may hang out in the inside part of the protein. The 3D shape is due to other interactions besides hydrophobic interactions. Ionic bonds, Van der Waals interactions, disulfide bonds, and hydrogen bonds- all involving the R groups- also _______ the folding occurring in tertiary structure. We’ve been talking about a polypeptide chain that has been folded into a functional protein.
But proteins can be made of 1 or _______ polypeptide chains and in quaternary structure-- Each of these polypeptide chains can be a subunit and interactions between them such as hydrogen bonds or disulfide bonds can keep them together. Who is doing this folding anyway? Are the proteins just folding themselves? Well, the interactions mentioned like hydrogen bonds and R group interactions are occurring depending on the protein’s own amino acids. Folding is far more complex than that, and there can be intermediate steps involved when a protein is folding. In fact, there’s a phrase you can search called the protein-folding problem to learn more about the questions scientists continue to explore regarding protein folding. Research has shown that proteins often have help in the folding process. Chaperonins, for example, are proteins that can _______ with the folding process. They have almost a barrel shape. Proteins go into them, and the chaperonin tends to have an environment that is _______ for the proteins’ folding. This can help the protein to be folded correctly so it’s functional.
All of these interactions we mentioned in primary, secondary, tertiary, and quaternary structure are paramount for a mature protein to have its correct shape so it can carry out its function. And that’s very relevant! There are many _______ that are related to protein misfoldings.
One last thing we haven’t mentioned: each protein has an ideal environment for functioning which might include a certain temperature or _______ range. If the protein is exposed to something outside of its ideal temperature or pH range- exposed to high heat for example- you can disrupt the interactions that we have talked about taking place at the different structural levels. This can _______ the protein, which disrupts its shape. This prevents it from functioning correctly. And depending on what caused it to be denatured, sometimes you are interfering with many levels of protein structure. Sometimes, it’s just one or two levels. Sometimes denaturing a protein may be _______ . But in many other cases…it’s not. The environment that a protein is in definitely matters for its functioning.
