food Flashcards
Nutrition
Nutrition is the way an organism gains and
uses food
Food (nutrition) is needed for:
Energy
Growth of new cells and repair of existing
cells, tissues, organs, etc.
To make the chemicals needed for
metabolic reactions
how many common elements in food
six
How many trace elements in food
three
how many dissolved salts
five
chemical elements
C, H, O, N, P, S
Dissolved Salts
Na, Mg, Cl, K, Ca
trace elements
Fe, Cu, Zn
There are 4 main types of biomolecules
found in food;
Carbohydrates
Lipids (fats & oils)
Proteins
Vitamins
Carbohydrates contain the elements
Carbon
Hydrogen
Oxygen
The general formula for a carbohydrate is
Cx(H2O)y
There are 3 types of carbohydrate;
Monosaccharides
Disaccharides
Polysaccharides
monosaccharides
single sugar molecules
simple sugars
soluble in water
sweet to taste
smallest carbohydrate unit
example of monosachhrides
glucose, fructose
where are monosaccharides found
fruit
Disaccharides
Made of two sugar units joined together –
known as double sugar molecules
soluble in water
sweet to taste
example of Disaccharides
sucrose, lactose, maltose
Disaccharides are Found in:
table sugar, milk
Polysaccharides
Many sugar molecules joined together
Not soluble in water
Do not taste sweet
Example of Polysaccharides
starch, cellulose
Polysaccharides are found in
bread, pasta, cereals
Sources of Carbohydrates
Bread
Pasta
Rice
Potatoes
Fruits
Sweets
Baked goods
structural role of carbohydrates
Cellulose forms
plant cell walls
metabolic role of carbohydrates
Glucose is broken
down during
respiration to
release energy
Glucose is made
during
photosynthesis
Lipids include
fats, oils, steroids, waxes
lipids are made up of the elements
carbon
hydrogen
oxygen
Difference between carbohydrates and lipids in their chemical structure
lipids have very little oxygen compared to carbohydrates