Regents Biology The Chemistry of Life What are living creatures made of? Why do we have to eat?

Regents Biology  96% of living organisms is made of: carbon (C) oxygen (O) hydrogen (H) nitrogen (N) Elements of Life

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  to make ATP ATP

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  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 How do we make these molecules? We build them!

Regents Biology Building large molecules of life  Chain together smaller molecules  building block molecules = monomers  Big molecules built from little molecules  polymers

Regents Biology  Small molecules = building blocks  Bond them together = polymers Building large organic molecules

Regents Biology How to build large molecules  Synthesis  building bigger molecules from smaller molecules  building cells & bodies  repair  growth  reproduction + ATP

Regents Biology Building important polymers sugar – sugar – sugar – sugar – sugar – sugar nucleotide – nucleotide – nucleotide – nucleotide Carbohydrates = built from sugars Proteins = built from amino acids Nucleic acids (DNA) = built from nucleotides amino acid amino acid – amino acid – amino acid – amino acid – amino acid –

Regents Biology How to take large molecules apart  Digestion  taking big molecules apart  getting raw materials  for synthesis & growth  making energy (ATP)  for synthesis, growth & everyday functions + ATP

Regents Biology Example of digestion starchglucose ATP  Starch is digested to glucose

Regents Biology Example of synthesis amino acidsprotein amino acids = building block protein = polymer  Proteins are synthesized by bonding amino acids

Regents Biology Carbohydrates

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 Proteins

Regents Biology Proteins: Multipurpose molecules

Regents Biology collagen (skin) Proteins insulin Examples  muscle  skin, hair, fingernails, claws  collagen, keratin  pepsin  digestive enzyme in stomach  insulin  hormone that controls blood sugar levels pepsin

Regents Biology Proteins  Function:  many, many functions  hormones  signals from one body system to another  insulin  movement  muscle  immune system  protect against germs  enzymes  help chemical reactions

Regents Biology Proteins  Building block = amino acid amino acid – amino acid – amino acid – amino acid – —N——N— H H H | —C— | C—OH || O variable group amino acids  20 different amino acids There’s 20 of us… like 20 different letters in an alphabet! Can make lots of different words

Regents Biology Lipids: Fats & Oils

Regents Biology Lipids Concentrated energy molecules

Regents Biology Lipids  Examples  fats  oils  waxes  hormones  sex hormones  testosterone (male)  estrogen (female)

Regents Biology Lipids  Function:  energy storage  very concentrated  twice the energy as carbohydrates!  cell membrane  cushions organs  insulates body  think whale blubber!

Regents Biology Structure of Fat not a chain (polymer) = just a “big fat molecule”

Regents Biology Saturated vs. unsaturated saturatedunsaturated

Regents Biology Other lipids in biology  Cell membranes are made out of lipids  phospholipids  heads are on the outside touching water  “like” water  tails are on inside away from water  “scared” of water  forms a barrier between the cell & the outside

Regents Biology Penguins gone bad! Any Questions?

Regents Biology Old Food Pyramid

Regents Biology New Food Pyramid