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 ATP

Regents Biology Do Now:  Hand in your pH lab.

Regents Biology 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 The New Food Pyramid

Regents Biology  Water  65% of your body is H 2 O  water is inorganic  doesn’t contain carbon  Rest of you is made of carbon molecules  organic molecules  carbohydrates  proteins  fats  nucleic acids Don’t forget water

Regents Biology Carbohydrates: OH H H HO CH 2 OH H H H OH O Energy molecules

Regents Biology Carbohydrates  Building block molecules = sugar sugar - sugar - sugar - sugar - sugar sugars

Regents Biology sucrose Carbohydrates  Function:  quick energy  energy storage  structure  cell wall in plants  Examples  sugars  starches  cellulose (cell wall) glucose C 6 H 12 O 6 starch

Regents Biology Sugars = building blocks  Names for sugars usually end in  glucose  fructose  sucrose  maltose OH H H HO CH 2 OH H H H OH O glucose C 6 H 12 O 6 sucrose fructose -ose maltose

Regents Biology Building carbohydrates  Synthesis | glucose | glucose 1 sugar = monosaccharide 2 sugars = disaccharide | maltose mono = one saccharide = sugar di = two

Regents Biology Building carbohydrates  Synthesis | fructose | glucose 1 sugar = monosaccharide | sucrose (table sugar) 2 sugars = disaccharide How sweet it is!

Regents Biology BIG carbohydrates  Polysaccharides  large carbohydrates  starch  energy storage in plants potatoes  glycogen  energy storage in animals in liver & muscles  cellulose  structure in plants cell walls  chitin  structure in arthropods & fungi exoskeleton poly = many

Regents Biology Building BIG carbohydrates glucose + glucose + glucose… = starch (plant) glycogen (animal) energy storage polysaccharide

Regents Biology Digesting starch vs. cellulose starch easy to digest cellulose hard to digest enzyme

Regents Biology Cellulose  Cell walls in plants  herbivores can digest cellulose well  most carnivores cannot digest cellulose  that’s why they eat meat to get their energy & nutrients  cellulose = roughage  stays undigested  keeps material moving in your intestines

Regents Biology Helpful bacteria  How can cows digest cellulose so well?  BACTERIA live in their stomachs & help digest cellulose-rich (grass) meals Eeeew… Chewing cud?

Regents Biology Let’s build some Carbohydrates! EAT X

Regents Biology Activities  building starch by bonding together paper glucose molecules  eat carrots, celery, cookies