Chapter 5: Protein Flashcards
Define what a protein is.
Proteins are macromolecules and polypeptides. Polypeptides are compounds that have 10
– 100 or even more molecular subunits. Every subunit is a small molecule that we call an amino acid, which we have linked together by peptide bonds. Proteins fill vital roles in the body that no other macronutrient can fill.
List the four levels in a protein’s structure.
The protein’s shape is going to determine its role and function within the body. We have four total levels in every protein.
i. The unique sequence of amino acids in a polypeptide chain that is determined through genetics makes the primary structure of the protein.
ii. Next, the local folding of the polypeptide chain makes the secondary structure. The more common structures are the alpha-helix chain and the beta-pleated sheet.
iii. Third, the combinations of chains and sheets make up the shapes of the proteins. The tertiary structure is the 3-d shape of the polypeptide. The interactions of the R groups between the individual amino acids creates the 3-d structure.
iv. Some proteins are made up of many polypeptides-known as subunits. The quaternary structure is formed based on the interactions between these subunits.
What is each amino acid made out of? (Know the bonded parts)
Amino acids are the building blocks of protein. Every single amino acid is going to be made up of five things.
1. A central carbon that may also be called the alpha carbon.
2. An amino group that is made up of a nitrogen and some hydrogen
atoms.
3. A carboxyl group which is a functional group that has carbon,
oxygen, and hydrogen.
4. A hydrogen atom.
5. The R group, which is a unique functional group that varies
depending on the type of amino acid.
What roles do the proteins take in the body? List a lot of the main proteins we see and the sources that they are often found in.
Roles are among the most diverse molecules in the body and have several very unique properties and roles they take on. These roles are:
a. Contractile
b. Hormonal
c. Structural
d. Transporter
e. Enzymes
f. Receptors
What are the names Branched-Chain Amino Acids? And what do they do? Are these often used as supplements?
Branched-chain amino acids are essential amino acids.
The three amino acids are isoleucine, leucine, and valine.
Together, these three amino acids make up around 35 percent of the amino acid content of our muscle tissues and is used by the body for energy. In times of stress, injury, or exercise, the body will use a high amount of these BCAAs to keep the nitrogen balance. These amino acids have a long history of being used as both medicine and supplements. They have often helped people in stressed states to help with the stimulus of protein synthesis and maintenance of the nitrogen balance.
Determine what is meant by calling a protein complete, incomplete, and complementary.
(search online for information on complementary proteins)
Complete proteins:
-have the essential amino acids in sufficient levels for the maintenance of normal growth rate and body weight.
- have a high biological value.
- mostly see animal proteins as complete, and the plant proteins as lacking some essential amino acids.
Explain the digestion process and its main steps, as it goes for the amino acids/proteins
Protein digestion can have many factors that change the shape and chemistry of the protein itself. Things like changing temperature, high salt levels, alcohol, mechanical agitation, and chemical exposure will alter the shape of the protein. The mouth has mechanical breakdown where large chunks of protein are split into smaller pieces of protein. There are no enzymes in saliva that break down the proteins, but the saliva does help to move the bolus. The gastric juices made up of hydrochloric and pepsin work to break down the protein. The acidic environment unfolds the proteins and denatures them further. Most of the digestion of proteins will happen in the small intestine with the use of protease. When chyme enters, the pancreas releases chymotrypsin and trypsin. Transport proteins take the amino acids to the liver for them to then be able to be sent out to the bloodstream.
what is growth hormone?
a hormonal protein released from the pituitary gland to stimulate growth, cell regeneration and repair, and cell reproduction. GH also acts homeostatically to increase blood glucose levels.
what’s the difference between essential, non-essential, and conditional amino acids?
Essential amino acids must be included from the diet bc they are not made in the body.
Non-essential amino acids can be produced in the body when needed.
Conditional aminos acids are necessary in the diet for special circumstances, such as illness or intense athletic training.
What are the three BCAAs?
leucine, isoleucine, valine
when might muscle release amino acids to be used as energy?
when under severe calorie restriction
Of the BCAAs, which amino acids is the most used by the body?
Leucine
What role does the pancreas play in the digestion of protein?
produces protease and releases trypsin
Most protein digestion happens after chyme moves into the
small intestine
