Proteins - 3 Flashcards
Function:
- carry out necessary cell functions like growth and repair
- form structures in your body like muscles, fingernails, hair, and fur
muscle structure
depends on protein - protein interactions
transport
across cell membranes involves proteins that control what goes in and out of the cell. This regulates ions, oxygen, and carbon dioxide.
Examples of proteins:
amino acid, polypeptide chain, enzyme
enzymes
almost all chemical reactions in a cell are catalyzed by this protein
how is information such as neurotransmitters transferred?
proteins transfer them through nerve cells and hormones in the blood
chemical formula
hydrogen, oxygen, carbon, nitrogen, and sometimes sulfur
monomer
20 amino acids
Amino acids have
amino group, carboxyl group, and a side group (R)
polypeptide chain
a chain of amino acids bonded together
carboxyl group + amino group –>(Dehydration)–> Peptide bond
Shape
3D shape, uniform backbones with differing side chains (R groups) that interact
primary structure
the sequence of amino acids in the polypeptide chain
secondary structure
proteins fold into one of two patterns: alpha helix and beta sheets
these patterns are a result of hydrogen bonding between R groups (side chains)
tertiary structure
the protein takes on its 3D shape as the amino acid folds back on itself when certain regions of the chain react with each other
- these interactions can be a result of the hydrophobic effect experienced wen proteins are in aqueous (water) environments.
quaternary structure
the result of two or more polypeptides interacting with each other to make a functional protein molecule.
- the different polypeptides are often called subunits which may be identical or different
