Food Flashcards
Why do organisms need food?
- for energy
- growth and repair
- to make chemicals for metabolic processes
How many elements are present in food?
14 elements
6 most common elements are
- carbon
-hydrogen
-oxygen
-nitrogen
-sulfur
-phosphorus
5 elements that are present in dissolved salts
- sodium
-magnesium
-chlorine
-potassium
-calcium
So Many Cats Can’t Pounce
Name the 3 trace elements
- iron
- copper
- zinc
What are biomolecules?
Biomolecules are chemicals that are made inside living things
What are the 4 major biomolecules in food?
- carbohydrates
-lipids
-minerals
-vitamins
What are the elements in carbohydrates
- carbon
-hydrogen
-oxygen
formula Cx(H2O)y- where x and y are the same value
example of monosaccharide?
Glucose and fructose C6H12O6
single sugar unit
3 types of carbohydrates
monosaccharides
disaccharides
polysaccharides
What are the sources of protein?
Meat, fish, yogurt, cheese, eggs and nuts
Example of disaccharides
Maltose and sucrose
Example of polysaccharides
Starch, cellulose and glycogen
What are the characteristics of starch?
- made of many glucose molecules joined
- easily digested
-carbohydrate stored by plants
Found in pasta and potatoes
Characteristics of cellulose
-made of many glucose molecules molecules joined together but with more cross bonding than starch
-very strong
-difficult to digest
Found in plant cell walls
Characteristics of glycogen
Complex polysaccharide
Large number of glucose molecules arranged in branches chains
Animals store it in their liver and muscles
What are the sources of carbohydrates?
Bread
Pasta
Rice
Potatoes
Cakes
What is the structural role of carbohydrates?
Cellulose is what forms the plant cell walls
Glycogen
What is the metabolic role of carbohydrates?
-glucose is made in photosynthesis
-glucose is broken down during respiration to carry out metabolic reactions
What are the elements present in lipids?
-carbon
-hydrogen
-oxygen
What is the difference between fats and oils at room temperatures?
Fats are solid at room temperature
Oils are liquid at room temperature
What does the structure of a triglyceride consist of?
Three fatty acid chains attached to a molecule of glycerol
What is the structure of a phospholipid?
One molecule of glycerol with one phosphate group and two fatty acid tails
What are the sources of lipids?
Butter, cream, oils and fat from meat
Structural role of lipids
Insulator for animals
Protection of organs
Important energy store for humans and plants
Phospholipid are an important structure in cell membranes
Metabolic role of lipids
Lipids can be broken down in respiration to release energy
Energy storage
Hormone production
Define phospholipid
Phospholipids are a fat like substance in which one fatty acid is replaced by a phosphate group
What are the elements of protein?
-carbon
-hydrogen
-oxygen
-nitrogen