Chapter 5 (Section A) Flashcards
Roles of protein in the diet (5)
providing structure and growth, catalyzing reactions, signaling, supporting immune activity, and transporting across cell membranes
Although proteins are not a primary source of energy, they can be used for energy (2):
during intense exercise or when nutrition is inadequate
Why is balancing protein intake important?
To avoid the formation of harmful waste products and to prevent loss of muscle mass
The body converts excess protein to _________ and increases the blood levels of which two metabolic waste products?
Fat; ammonia and uric acid
A toxic metabolic waste product produced from the metabolism of nitrogen containing compounds like protein and amino acids
ammonia
a toxic metabolic waste product filtered by the kidneys as a result of the metabolism of nitrogen containing compounds
uric acid
A protein is a macromolecule and a _____________ , a compound containing __ to over _____ molecular subunits. Each subunit is a small molecule known as an _________ which are linked together by a ____________.
polypeptide; 10 to 100; amino acid; peptide bond
an organic compound that is used as a precursor for other molecules in the body
amino acid
the bond that links amino acids together to form a protein
peptide bond
Four levels of structure in each protein. What makes the primary structure?
The unique sequence of amino acids in a polypeptide chain that is determined by genetics makes the primary structure.
What makes the secondary structure of a protein?
The local folding of the polypeptide chain.
What makes up the shapes of proteins?
Combinations of chains and sheets
What is the tertiary structure of proteins?
The 3-D shape of the polypeptide
What is the quaternary structure of proteins?
The quaternary structure is formed based on the interactions between subunits.
The _________ is the primary structure that creates the secondary helix. A series of helices creates a _____________ which, when combined with other polypeptide chains, creates the functional protein structure
amino acid, polypeptide chain
In terms of nutrition, it is important to consider the _________ __________ _________ rather than whole proteins
amino acid subunits
Metabolic process that converts ammonia to the waste product urea
urea cycle
the molecules that transmits a signal across the synapse between two neurons
neurotransmitters
each amino acid is made up of a central carbon atom known as the
alpha carbon
What is bonded to the alpha carbon (4)
an amino group, a carboxyl group, a hydrogen atom, and the R group.
a chemical grouping (functional group) made up of nitrogen and hydrogen atoms
amino group
a functional group containing carbon, oxygen, and hydrogen
carboxyl group
A unique functional group that varies depending on the type of amino acid
R group
Compounds consisting of two or more amino acids linked together by peptide bonds
peptides
