In living organisms, the molecules that make us function are very large, they form macromolecules.
In order to build the necessary macromolecules, we need certain nutrients
Our bodies require six basic components: Carbohydrates, Proteins, Fats, Vitamins, Minerals, Water!
-Carbohydrate: Sugars-These are our primary source of energy
a) Monosaccharides
-single sugars, Ex. fructose, galactose, glucose
b) Polysaccharides
-complex: result of 3 or more monosaccharides linking together
-need to be digested before we can absorb them
- Some are used for energy storage, ex. glycogen, starch
-some are structural, ex. cellulose, chitin
Dietary sources of carbohydrates-We use carbs as our main source of energy, grains, potatoes, breads, cereals, fruits.
PROTEIN
The functional molecules
Help chemical reactions take place (ex. enzymes)
Repair and maintain the cell
Transport materials around the body
Ex. amylase, lipase, pepsin, hemoglobin, hair
-Amino acids: small molecules containing a central C atom and a side chain
There are 20 amino acids in human food
8 of those are essential: we do not produce them and therefore must EAT them
-Amino acids link together during protein synthesis
Most functional proteins will contain hunderds and thousands of amino acids linked together
-protein function depends on its 3-dimensional shape, its structure
protein function depends on its 3-dimensional shape, its structure
Dietary sources of proteins
Meat, beans, nuts, seeds, milk products
3. LIPIDS: the fats of life
Functions:
Energy: these are our long-term energy storing molecules!
Structural: cell membrane phospholipids, cholesterol