1. The Nature of Life Section 2-4: The Chemistry of Living Things

2. Elements vs. Compounds Element – a pure substance that cannot be broken down into any simpler substances by ordinary means Element – a pure substance that cannot be broken down into any simpler substances by ordinary means Examples: Helium, Copper, Zinc, Sulfur, Lead, etc. (everything on the Periodic Table) Examples: Helium, Copper, Zinc, Sulfur, Lead, etc. (everything on the Periodic Table) Compound – two or more different elements chemically joined (water, sugar, salt, carbon dioxide, rust, etc.) Compound – two or more different elements chemically joined (water, sugar, salt, carbon dioxide, rust, etc.)

3. Elements vs. Compounds The properties of compounds are often totally different from those of the elements that make them up The properties of compounds are often totally different from those of the elements that make them up For Example – C 6 H 12 O 6 is a molecule of sugar (glucose). It is nothing like pure carbon (carbon rods or diamonds), pure hydrogen (an explosive gas) or oxygen (another gas) For Example – C 6 H 12 O 6 is a molecule of sugar (glucose). It is nothing like pure carbon (carbon rods or diamonds), pure hydrogen (an explosive gas) or oxygen (another gas)

4. Inorganic Compounds Compounds that do not contain carbon Compounds that do not contain carbon The exception is carbon dioxide (CO 2 ) which is considered inorganic The exception is carbon dioxide (CO 2 ) which is considered inorganic Examples include: Ammonia (NH 3 ) Salt (NaCl) Water (H 2 O) Steel/rust Glass Metallics Minerals Plant Fertilizer (N,P,K)

5. Organic Compounds Compounds containing carbon Compounds containing carbon Those basic to life include: Those basic to life include: Carbohydrates Carbohydrates Lipids (fats and oils) Lipids (fats and oils) Proteins Proteins Nucleic Acids Nucleic Acids

6. Carbohydrates Composed of carbon, hydrogen and oxygen Composed of carbon, hydrogen and oxygen Includes sugars, starches, and cellulose Includes sugars, starches, and cellulose The product of photosynthesis; all carbohydrates originate from photosynthesis whose end product is the simple sugar glucose The product of photosynthesis; all carbohydrates originate from photosynthesis whose end product is the simple sugar glucose

7. Carbohydrates Glucose molecules can be joined together to form: Glucose molecules can be joined together to form: starch molecules - plants store energy in the form of starch starch molecules - plants store energy in the form of starch Cellulose molecules – the primary construction material of plants Cellulose molecules – the primary construction material of plants Glucose can also be broken down during respiration to release energy to fuel other cellular processes Glucose can also be broken down during respiration to release energy to fuel other cellular processes

8. Carbohydrates - Glucose

9. Carbohydrates - Starch

10. Carbohydrate - Cellulose

11. Lipids: Fats and Oils Composed of carbon, hydrogen and oxygen (the same as carbohydrates) Composed of carbon, hydrogen and oxygen (the same as carbohydrates) Essential to life because they are part of all cell membranes Essential to life because they are part of all cell membranes Used to store energy in animals Used to store energy in animals At room temperature fats are solid while oils are liquid At room temperature fats are solid while oils are liquid

12. Lipids

13. Proteins Composed of carbon, hydrogen, oxygen and nitrogen and sometimes sulfur Composed of carbon, hydrogen, oxygen and nitrogen and sometimes sulfur All made of the same 20 building blocks called amino acids All made of the same 20 building blocks called amino acids Humans have an estimated 30,000 different proteins Humans have an estimated 30,000 different proteins Each protein has a unique number and sequence of amino acids; a change in one amino acid creates a different protein that may not function Each protein has a unique number and sequence of amino acids; a change in one amino acid creates a different protein that may not function

14. Proteins An essential part of all living cells An essential part of all living cells Proteins are part of all cell membranes, regulating transport of substances through the membrane Proteins are part of all cell membranes, regulating transport of substances through the membrane As enzymes proteins regulate all metabolic activities of cells As enzymes proteins regulate all metabolic activities of cells Enzymes act as catalysts – substances that speed up or slow down chemical reactions without being changed themselves. Enzymes act as catalysts – substances that speed up or slow down chemical reactions without being changed themselves.

15. Proteins in Animals Make up 50% of the body’s dry matter Make up 50% of the body’s dry matter Collagen (in skin, bones, tendons, and cartilage) muscle fibers, hair, and nails, are all protein Collagen (in skin, bones, tendons, and cartilage) muscle fibers, hair, and nails, are all protein Protein is a vital part of blood (hemoglobin) Protein is a vital part of blood (hemoglobin) Antibodies of the immune system are protein Antibodies of the immune system are protein

16. Protein

17. Nucleic Acids Composed of carbon, hydrogen, oxygen and nitrogen Composed of carbon, hydrogen, oxygen and nitrogen The “Blueprints” of life The “Blueprints” of life Very large molecules/compounds that store information that helps the body make the proteins it needs Very large molecules/compounds that store information that helps the body make the proteins it needs Controls the assembly of amino acids into proteins Controls the assembly of amino acids into proteins

18. Nucleic Acids DNA – Deoxyribonucleic acid DNA – Deoxyribonucleic acid Stores the information/code Stores the information/code Transmits it from parent to offspring Transmits it from parent to offspring RNA – Ribonucleic acid RNA – Ribonucleic acid Translates the message of DNA into proteins Translates the message of DNA into proteins

19. DNA

20. The End