Unit 2 - Nature's Chemistry (Proteins) Flashcards
(10 cards)
What are fibrous proteins?
Fibrous protein molecules are long, spiral chains that are folded to form strong structures such as hair, fingernails and muscle tissue. They are strong and generally insoluble in water.
What are globular proteins?
Globular proteins have the spiral chains folded into spherical shapes and are responsible for substances in the human body such as haemoglobin,
enzymes and certain hormones like insulin. They are generally soluble in water.
What are proteins?
Proteins are natural condensation polymers formed by joining together thousands of
amino acid molecules.
Which functional groups do amino acids contain?
- Amine group (-NH2)
- Carboxyl group (-COOH)
How are proteins formed?
Proteins are formed in a condensation reaction when amino acid molecules join together and a water molecule is removed. The new bond formed in protein molecules where amino acids have joined (-CONH) is called an amide link or a peptide link.
What are essential amino acids?
Proteins we must acquire through our diet, as our bodies are not able to make up these specific amino acids.
How are esters broken?
Similar to esters, protein molecules can be broken down by hydrolysis (the opposite of condensation). Water molecules break apart the peptide links of the protein molecule, leaving separate amino acid molecules. Breaking each peptide link leaves amine and carboxyl groups.
How are proteins digested?
During digestion, enzymes in our bodies break the proteins we eat down into amino acids (by hydrolysis). These amino acids are transported around the body by blood. In the bloodstream, condensation reactions build the amino acids up to produce proteins required by the body.
How are proteins held together?
However the protein chains are arranged (fibrous or globular), they are held in these shapes by intermolecular bonding between the side chains of the amino acids involved.
What happens when proteins are heated?
The molecules become agitated and move around causing the intermolecular bonds between molecules to be broken. This allows the protein to denature (change shape) which can change the texture of some foods.
