What are living creatures made of?
Why do we have to eat?
Regents Biology
2006-2007
ELEMENTS OF LIFE
▪96% of living organisms is made of: ■carbon
(C)
■oxygen (O)
■hydrogen (H)
■nitrogen (N)
Regents Biology
MOLECULES OF LIFE
▪Put C, H, O, N together in different ways to build living organisms
▪What are bodies made of? carbohydrates ◆
▪sugars & starches
proteins
◆fats (lipids)
◆nucleic acids
◆
▪DNA, RNA
Regents Biology
WHY DO WE EAT?
▪We eat to take in more of these chemicals
Food for building materials
◆
▪to make more of us (cells)
▪for growth
▪for repair
Food to make energy
◆
▪calories
▪to make ATP
Regents Biology
ATP
WHAT DO WE NEED TO EAT?
▪Foods to give you more building blocks
& more energy
▪for building & running bodies
carbohydrates
◆proteins
◆fats
◆nucleic acids
◆vitamins
◆minerals, salts
◆water
◆
Regents Biology
DON’T FORGET WATER
▪Water
65% of your body is H2O
◆water is inorganic
◆
▪doesn’t contain carbon
▪Rest of you is made of carbon molecules organic molecules
◆
▪carbohydrates
▪proteins
▪fats
▪nucleic acids
Regents Biology
How do we make these molecules?
We build them!
Regents Biology
2006-2007
BUILDING LARGE MOLECULES OF LIFE
▪Chain together smaller molecules building block molecules = monomers
◆
▪Big molecules built from little molecules polymers ◆
Regents Biology
BUILDING LARGE ORGANIC MOLECULES
▪Small molecules = building blocks
▪Bond them together = polymers
Regents Biology
BUILDING IMPORTANT POLYMERS
Carbohydrates = built from sugars sugar – sugar – sugar – sugar – sugar – sugar
Proteins = built from amino acids amino – amino – amino – amino – amino – amino acid acid acid acid
acid