L.2 - proteins Flashcards
What determines what a cell looks like & how it functions?
- proteins
What is the function of the enzyme protein?
Catalyze specific chemical rxns
What is the function of the structural protein?
- strengthen and protect cells and tissues
What is the function of the storage protein?
Store nutrients
What is the function of the regulatory protein?
Control the activities of proteins, genes, cells, and tissues
What is the function of the motile proteins protein?
Generate movement in cells and tissues
What is the function of the protective protein?
Defend against foreign invaders
What are amino acids?
- the building blocks of protein
What is the main structure of amino acids??
- central carbon and hydrogen
- an amino functional group (NH2)
- a carboxylic acid/or carbonyls tree functional group (OH-C=O)
- a side chain known as the r group
How many different amino acids are there and what groups are they put in?
- 20 amino acids
- placed in either polar, nonpolar, or electrically charged groups
What are the 4 levels of protein organization?
- Primary - amino acid sequence
- Secondary - results from hydrogen bonding btw amino acids
- Tertiary - depends on interactions among side chains
- Quaternary - results from interactions among polypeptides
What is a peptide bond?
- a bond between the 2 amino acids.
How does a peptide form?
- form as a dehydration synthesis.
- create a peptide bond between the carboxylic acid group of 1 amino acid and the amino group of another.
- this will form a dipeptide bond
- the now free n-terminal and c-term old dipeptides are available to react with further amino acids to make larger polypeptides and eventually proteins
How strong are petite bonds?
- they are rigid but the adjacent R groups etc can rotate
What are the 2 structures of the ‘secondary structure’ of the formation of a protein?
- a-helix - hydrogen bonds hold the helix coils in shape
- b sheet - hydrogen bonds hold neighbouring strands of sheet together