Chapter 7 - Protein Flashcards
What are the three main groups of amino acids
- Nitrogen-containing amine group
- A carboxylic acids
- A side chain (rx)
What are the essential amino acids
- Histidine
- Isoleucine
- Leucine
- Lysine
- Methionine
- Phenylalanine
- Threonine
- Tryptophan
- Valine
What are the non-essential amino acids
- Alanine
- Asparagine
- Aspartate
- Glutamate
- Serine
- Selenocysteine
What are the conditionally essential amino acids
- Arginine
- Cysteine
- Glutamine
- Glycine
- Proline
- Tyrosine
What determines if an amino acid is non essential
If they can be converted into an essential amino acids through transamination
What determines if an amino acid is conditionally essential
They are non-essential until the body can’t make enough of them
What is a complete protein
foods that have all nine amino acids,, if they are missing one or more essential amino acid they are considered incomplete amino acids
Describe the primary structure of a protein
The first level of a protein structure arises from adjacent amino acids bonding to each other through peptide bonds to form a polypeptide chain
Describe the secondary structure of a protein
Hydrogen bonds between two adjacent amino acids lead to the formation of alpha helices and beta-pleated sheets
Describe the tertiary structure of a protein
Interactions between amino acid side chains leads to further folding of the polypeptide chain. This may result in a functional protein
Describe the quaternary structure of a protein
Several proteins with a tertiary structure bind together to form the final protein
What is protein denaturation
A protein is considered denatured when it loses its folded three-dimensional structure. Caused by acids, head, agitation and cannot be undone
Describe protein digestion
protein undergoes only mechanical digestion in the mouth. In the stomach the protein is denatured by hydrochloric acid and it is digested by pepsin. In the small intestine the protein is further digested by proteases including chymotrysin and trypsin. There is minimal digestion in the small intestine
What are the functions of proteins in the body
- Body structure
- Transport
- Enzymes
- Movement
- fluid balance
- protection from disease
- Energy
Describe proteins contribution to body structure
bones, muscles, skin and every body organ contains protein
- Collagen is the main structural protein
- Elastin is another key structural protein
Describe how protein is used for transportation
- Protein tracks in cells allow substances to all along them, permitting transport around cell
- Protein channels regulate movement into and out of the cell
- The blood protein hemoglobin transports oxygen around the body
Describe how protein is used for movement
The muscle contains two proteins called myosin and actin. When myosin proteins attach to actin proteins and kink their heads, muscle contraction occurs
Describe how proteins contribute to fluid balance
Water is attached to the positive and negative charges of the amino acids found in the blood proteins
- This draws water into the blood and out of the extracellular spaceW
What is edema
A build up of fluid that can result from having low blood proteins
Deserve the function of protein in the protection from diseases
- collagen in skin helps to restrict what can enter the body
- if infectious agents enter, proteins called antibodies stick to these agents, promoting their removal and limiting the harm they can cause on the body
Describe proteins contribution to energy
If there is a lack of carbohydrates in the body amino acids can be sed in the citric acid cycle
- Protein also provides 4 kcal/g of energy
What is marasmus
Wasting syndrome
- occurs when energy and protein are deficient
- Promotes anemia, dehydration, heart irregularities, body temperature dysregulation
What is kwashiorkor
- Believed to occur when protein is deficit but energy is still sufficient
- Evidenced by a distended swollen abdomen and an otherwise slim appearance
( eats one food repeatedly such as rice which is an incomplete protein)
How does protein promote a caloric deficit
- Promoting fullness
- Contributing to carbohydrate and lipid metabolism
- Requiring more energy to digest and absorb it ( higher thermic effect)
