Break Up And Make Up Of Macromolecules Flashcards
Macromolecules - polymers & monomers
Macromolecules are also known as polymers. Polymers are made up of long chains/networks of smaller molecules called monomers. These macromolecules can have molecular weights ranging from a few thousand to millions of gmol-1. Polymers can occur naturally or be manufactured (hair, proteins, carbohydrates, lipids, and DNA).
gmol-1
g (grams), mol (quantity of atoms), -1 (per second)
Protein - break up and make up
The peptide bonds in proteins can be broken down in the body to release amino acids. Amino acids can join together to form proteins.
Building chains
Once the chain of amino acids join together, the polymer (protein) can fold over, depending on what it is needed for.
Primary protein structure
Sequence of a chain of amino acids.
Secondary protein structure
Local folding of the polypeptide chain into helices or sheets: alpha (a) helix, beta (b) pleated sheet.
Tertiary protein structure
3D folding pattern of a protein, due to side chain interactions (B-pleated sheets & a-helices together).
Quaternary protein structure
Protein consisting of more than one amino acid chain (e.g. haemoglobin).
Rebuilding proteins
Proteins can be broken down and reformed by combining the amino acids in a different combination.
Condensation reaction - forming disaccharides and polysaccharides
Polysaccharides are formed by combining three or more monosaccharides through a condensation reaction. During this process, the hydrogen atom (H) from one monosaccharide and the hydroxyl group (OH) from another combine to form a water molecule (H2O) - it loses water. This process creates a covalent bond and creates a disaccharide. Adding more monosaccharides to the chain forms a polysaccharide. Each time a monosaccharide is added, H2O is produced (condensation).
Joining monosaccharides to form a disaccharide
If two glucose molecules react, then the (H) of one molecule, and (OH) of another are released (H2O). The individual molecules are held together by a glycosidic bond.
Condensation reaction - forming starch
Starch is formed when lots of glucose molecules undergo condensation reactions to bond with one another - forming long chains (glucose molecule chains).
Hydrolysis reaction
Polysaccharides can be broken down into disaccharides or constituent monosaccharides through a hydrolysis reaction (adding water) and by using enzymes.
Examples of a polysaccharide, disaccharide, and monosaccharide
Starch (polysaccharide) made up of long chains of glucose. Maltose (disaccharide) made up of two glucose molecules, and fructose (monosaccharide) a single sugar molecule.
Lipids - ester bonds
Made from from fatty acids and glycerol joined through a condensation reaction. This forms an ester bond.
Triglycerides
The form in which fat energy is stored in the adipose tissue. In the formation of triglycerides, 1 glycerol molecule is joined to 3 fatty acid molecules. Each fatty acid attaches to 1 of the glycerol’s 3 carbons through the oxygen atom (O) in the ester bond. The R-group of the fatty acid can be saturated/unsaturated. The process releases 3 water molecules (H2O).
Formation of a triglyceride
3 fatty acids + 1 glycerol molecule —> 1 triglyceride molecule + 3 water molecules.
3 ester bonds formed
Phospholipids - structure compared to triglycerides
1 glycerol, 2 fatty acids, and a phosphate group. Similar to triglycerides - 1 glycerol and 2 fatty acids connected to the glycerol via ester bonds. However, the 3rd fatty acid chain (in triglycerides), is replaced in phospholipids with a phosphate group covalently bonded to the glycerol.
Lipids - enzymes
Lipids, in particular triglycerides, are the most common fat in the body. They are broken down using enzymes (lipases) to form fatty acids and glycerol.
