The Chemistry of Life

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

2. Chemistry in Biology Chapter 6 6.1 Atoms, Elements, and Compounds 1. Atoms • Chemistry is the study of matter. A. Atoms are the building blocks of matter. • Neutrons and protons are located at the center of the atom. 1. Protons are positively charged particles. 2. Neutrons are particles that have no charge.

3. Chemistry in Biology Chapter 6 6.1 Atoms, Elements, and Compounds 3. Electrons are negatively charged particles that are located outside the nucleus.

4. Chemistry in Biology 6.1 Atoms, Elements, and Compounds 2. Elements • An element is a pure substance that cannot be broken down into other substances by physical or chemical means. • There are over 100 known elements, 92 of which occur naturally. • Each element has a unique name and symbol.

5. Chemistry in Biology 6.1 Atoms, Elements, and Compounds The Periodic Table of Elements • Horizontal rows are called periods. • Vertical columns are called groups.

6. 3. Elements of Life • 96% of living organisms is made of: • carbon (C) • oxygen (O) • hydrogen (H) • nitrogen (N)

7. What is a Molecule Covalent bonds hold 2 or more atoms together to form a molecule. A. Important Molecules • H2O Water • O2 Oxygen • CO2 Carbon Dioxide • C6H12O6 Glucose

8. Why do elements form molecules. • To fill their outer shell with electrons. • This is called bonding. • Two types of bonding a. covalent = Sharing b. ionic = Transferring 4. Molecules are formed by covalent bonding.

9. 4. Macro-molecules of Life A. Put C, H, O, N together in different ways to build living organisms B. What are bodies made of? 1. carbohydrates • sugars & starches 2. proteins 3. fats (lipids) 4. nucleic acids • DNA, RNA

10. How do we make these molecules? We build them!

11. 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

12. 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

13. What do all macromolecules have in common? C. They all contain Carbon • Has 4 valence electrons • Forms many types of covalent bonds. • Forms the backbone of all macromolecules

15. What do all macromolecules have in common? 2. They are all polymers • A polymer is a long molecule consisting of many similar building blocks called monomers What is a polymer? What is a monomer? 3. They are all assembled by a Dehydration reaction (Condensation).

16. 1 HO H 3 2 H HO Unlinked monomer Short polymer Dehydration removes a watermolecule, forming a new bond H2O 1 2 3 4 HO H Longer polymer (a) Dehydration reaction in the synthesis of a polymer Figure5.2A How are polymers assembled? Dehydration Reaction (Condensation) Water Making

17. 1 3 HO 4 2 H Hydrolysis adds a watermolecule, breaking a bond H2O 1 2 H HO 3 H HO (b) Hydrolysis of a polymer Figure 5.2B How are polymers taken apart? • Polymers are disassembled by • Hydrolysis (water Breaking)

18. Building large molecules of life • Chain together smaller molecules • building block molecules = monomers • Big molecules built from little molecules • polymers

19. Building large organic molecules • Small molecules = building blocks (Monomers) • Bond them together =polymers

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

21. How to build large molecules • Synthesis (Dehydration) • building bigger molecules from smaller molecules • building cells & bodies • repair • growth • reproduction + ATP

22. Example of synthesis amino acids = building block protein = polymer amino acids protein • Proteins are synthesized by bonding amino acids

23. How to take large molecules apart • Digestion (Hydrolysis) • taking big molecules apart • getting raw materials • for synthesis & growth • making energy (ATP) • for synthesis, growth & everyday functions + ATP

24. Example of digestion ATP • Starch is digested to glucose ATP ATP ATP ATP ATP starch glucose ATP

25. AnyQuestions? Penguins gone bad!

26. Old Food Pyramid

27. New Food Pyramid

28. 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