PROTEIN SECTION LECTURE #2 Flashcards
What percentage of body weight do proteins typically account for?
Proteins typically account for about 15% of body weight.
Name two types of structural proteins.
Collagen and muscle are two types of structural proteins.
What type of protein is amylase?
Amylase is an enzyme protein.
Can you list two transport proteins
Albumin and hemoglobin are two transport proteins mentioned.
What is the role of protective proteins?
Protective proteins play roles in the immune system, such as antibodies, and in blood clotting.
What are contractile proteins, and where are they found?
Contractile proteins responsible for movement
found in muscle
What type of protein is insulin classified as?
Insulin is classified as a protein-derived hormone.
What function do proteins have in fluid balance?
Proteins help maintain fluid balance through osmosis.
Are proteins commonly used by the body for fuel?
No, proteins are generally not used for fuel.
What function do proteins serve in pH regulation?
Proteins act as buffers to help regulate pH levels in the body.
What are the basic building blocks for all proteins?
Amino acids are the basic building blocks for all proteins.
What common structural components do all amino acids have?
All amino acids have a central carbon atom, a hydrogen atom, an amino group, a carboxyl group, and a variable “R” side chain.
What determines the different properties of amino acids?
The different features of the “R” side chain determine the different properties of amino acids.
What is the difference between essential and nonessential amino acids?
Essential amino acids cannot be synthesized by the body and must be obtained from the diet, while nonessential amino acids can be synthesized by the body.
Can you name three essential amino acids?
Three essential amino acids are lysine, leucine, and valine.
What are conditionally essential amino acids and under what circumstances?
Conditionally essential amino acids, such as arginine and glutamine, are not normally required in the diet but must be supplied under special circumstances, like illness or stress.
Why might an amino acid be classified as conditionally essential for infants?
An amino acid might be classified as conditionally essential for infants because they have a higher requirement for certain amino acids that are necessary for growth and development, and their bodies may not be able to synthesize enough of them.
How do side chains affect amino acids?
Side chains affect the role of amino acids within the body and determine where they reside, such as in cell surfaces or within core structures, and whether they are polar/hydrophilic or non-polar/hydrophobic.
What is an aliphatic side chain in an amino acid?
An aliphatic side chain in an amino acid consists of straight or branched carbon chains.
Which amino acids have an aromatic side chain?
The amino acids with an aromatic side chain are tryptophan, tyrosine, and phenylalanine.
Why are aromatic amino acids unique compared to other types?
Aromatic amino acids are unique because they contain a ring structure in their side chain, which can absorb ultraviolet light and is involved in various chemical reactions due to the stability of the ring structure.
What does the net charge of an amino acid indicate?
The net charge of an amino acid indicates its ionic character, which can be neutral (as in zwitterions), acidic with a negative charge (dicarboxylic), or basic with a positive charge (dibasic).
What determines the polarity of an amino acid?
The polarity of an amino acid is determined by whether it can interact with water, electrolytes, and minerals, and whether it can accept or donate hydrogen ions.
What makes an amino acid polar?
An amino acid is considered polar if it has double bonded oxygen or hydroxyl (OH) groups that are able to donate or accept hydrogen ions.
What characterizes a nonpolar amino acid?
A nonpolar amino acid is characterized by having hydrophobic side chains, typically with CH groups.
Can you provide an example of how an amino acid’s side chain affects its function in the body?
For example, polar amino acids with hydroxyl groups can interact with water and are therefore more likely to be found on the outside of proteins, interacting with the aqueous cellular environment. Meanwhile, nonpolar amino acids are often found in the interior of proteins, away from water.
