Protein and Amino acid Flashcards
protein accounts for how much of our total body mass?
15-16%
structural proteins:
keratin in skin and hair
protein enzymes:
glycolysis, citric acid cycle
transport proteins:
glucose transporter, GLUT4, lipoprotein
protective proteins:
antibodies
Functional proteins:
actin and myosin in muscles
signalling proteins:
hormones, insulin and glucagon
what are all proteins composed of?
individual amino acids building blocks
Amino acids are nitrogen containing compounds. T or F
T
The 4th group is unique for each amino acid, why?
has implications for protein structure and function
how many amino acids are commonly found in proteins?
20
how are amino acids connected?
connected enzymatically through a peptide bond
how are proteins created through DNA?
DNA is converted to RNA, read by a ribosome that connects amino acids together to form the protein
what can happen to the protein if there is a change in the sequence of DNA?
dramatic changes on the proteins function
ex. altered polypeptide shape in red blood cells causes sicle cell disease
what three ways are proteins broken down?
- Mechanical (chewing)
- Chemically (HCL in the stomach)
- Enzymatically (stomach and pancreatic enzymes)
what are single amino acids and small peptides absorbed by?
mucosal cells of the small intestine
once the amino acids and peptides are absorbed by the mucosal cells, what happens next?
peptides are broken down further and amino acids are transported to the liver
how does the body recognize allergies?
Dietary proteins may be absorbed without being completely digested
The immune system may recognize these dietary proteins as a foreign antigen and mount an immune response
what are the 3 steps in the body for an allergic reaction?
- First time, immune system is stimulated (sensitization)
- recognition as a foreign substance
- An immune response is mounted and an allergic reaction occurs
what is the avg half life of a protein
~ 7 hours
essential amino acids:
histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine
non essential amino acids:
arginine, cysteine (cystine), glutamine, glycine, proline, tyrosine, alanine, asparagine, aspartic acid (aspartate), serine