Chapter 5 – Carbon Compounds in Cells

1. Chapter 5 – Carbon Compounds in Cells Mr. Martino College Prep Biology

2. 5.1 Carbon is the main ingredient of organic molecules • Other than water, carbon-containing compounds are the most common in cells • Organic compounds: carbon-containing compounds synthesized by cells (> 2 million known) • Inorganic compounds: non-carbon based molecules such as water, oxygen, ammonia

3. Properties of Org. Comps. – con’t • Carbon skeleton: (backbone) chain of C atoms in organic molecules • Properties of Carbon: • Can form 4 single covalent bonds • C- skeletons may vary in length • Skeletons may be branched • Skeletons may form rings • Skeletons may have double bonds • Hydrocarbon: organic molecules only composed of carbon and hydrogen

4. Properties of organic compounds also depend upon functional groups which are groups of atoms attached to C skeletons • Functional groups are usually involved in rxns. • All are polar (O or N present) • Polarity makes them Hydrophilic: “water loving” which is important for life • Many molecules have more than one functional group

5. Monomer: single molecular units that build larger units • Polymer: many monomers linked together making a large molecule

6. Dehydration Synthesis: the process of linking monomers to form polymers • All unlinked monomers have -H and -OH • Water is released Ex. Building of all macromolecules • Hydrolysis:breaking down of large molecules into smaller molecules • Add water • Reverse of dehydration synthesis Ex. digestion

7. 5.2 Carbohydrates • Carbohydrates: “watered carbon” – large class of polymers including sugars and starches • Contain C, H and O in a 1:2:1 ratio (CH2O) • Monosaccharide: carbohydrate monomer • Most are sweet • Polar • Have 5 or 6 carbon skeleton

9. Carbohydrates – con’t • Oligosaccharide: short chain of 2 or more monosaccharides • Disaccharide: 2 monosaccharides • Ex: lactose, sucrose, maltose • Sucrose is the main carbohydrate of plant sap – used to nourish plant parts (we use for table sugar) • Maltose is grain sugar – used to nourish germinating seeds (we use to make beer)

10. Polysaccharides: polymers • of hundreds to thousands • of monosaccharides • Starch: a storage • molecule in plant parts • All glucose • Coils (helix) and • may or may not • be branched • Used for E • Potatoes, corn, grains

11. Cellulose: polysaccharide that serves to protect cells and support organisms • Most abundant organic compound on Earth • polymer of glucose • Unbranched rods • Joined by H-bonds • Cannot be hydrolyzed by most animals • Fiber is necessary but not as a nutrient

12. Glycogen: storage polysaccharide found in liver and muscle cells of animals • Polymer of glucose • Helical shape • Identical to starch except more extensively branched • Contains more E than starch • Too much is converted to fat

13. 5.3 Lipids • Lipids: Diverse compounds consisting of mostly C and H linked by nonpolar, covalent bonds • All are greasy or oily to the touch • Nonpolar = hydrophobic “water fearing” • Include fats, phospholipids, waxes, and steroids

14. Fat: large lipid made of a glycerol and three fatty acids – triglyceride • Glycerol – an alcohol with 3 C’s that have OH’s • Fatty acid – carboxyl with a hydrocarbon chain • Stores more than twice as much E than starch • Unsaturated: double bonds • Kinky – can’t pack tight • Oils (from plants) • Saturated: maximum # H’s • Solids (from animals)

15. Phospholipids:major component of cell membranes, protect surfaces, regulate functions • Similar to fats • Have P group & 2 fatty acids attached to glycerol • Waxes: protect, lubricate and cover fruits, animals and insects • A fatty acid + alcohol • More hydrophobic than fats • Prevents desiccation

16. Sterols: lipids whose C skeleton is bent to form 4 fused rings • 3 6-sided rings & 1 5-sided ring • Cholesterol is present in animal cell membranes, form vitamin D, bile salts for digestion of fats & makes sex hormones • Also known as steroids Nope, not them , HIM !!!

18. 5.4 Amino Acids and Protein Structure • Proteins: macromolecules essential to the structure and function of cells • Polymers of amino acids • Most diverse of all organic compounds • Seven major classes: • Structural – spider silk, hair, and fibers of tendons & ligaments, feathers and cartilage • Contractile – control muscle movement • Storage – (nutritious) stores amino acids such as albumin, milk, many seeds • Defensive – antibodies of blood that fight infection • Transport – move molecules & ions across cell membranes - includes hemoglobin which carries oxygen in blood • Signal (hormones)– certain hormones that carry messages • Enzymes – chemical catalysts that promote and regulate most all chemical reactions

19. Amino Acids and Protein Structure – con’t • Amino acids: monomers of proteins • 20 different kinds that make all the proteins possible • Have four parts bonded to a central carbon atom: • Amino group • Carboxyl group (acid) • Single hydrogen ion • R group – the one group that varies between them all • Determines the properties of the amino acid

20. Amino Acids and Protein Structure – con’t • Peptide bond: covalent bond that forms by dehydration synthesis & is only found in proteins • Occurs between the carboxyl group of one A. A. and the amino group of another • Forms polypeptides which can range from a few A. A.’s to thousands

21. 5.5 Protein’s 3-D Structure • There are 4 levels of protein structure • Proteins are one or more polypeptide chains folded in a unique shape • Shape is extremely important for the enzyme to recognize and attach to its target • Denaturation: the process of changing a protein’s shape so it can no longer function properly • Ex. Cooking egg whites or meats • Caused by heat, pH change, salt concentration change, or chemical balance change

22. 5.7 Nucleotides and Nucleic Acids • Nucleotides: monomers that make up nucleic acids and ATP (adenosine triphosphate) • Consist of a 5-C sugar (deoxyribose in DNA, ribose in RNA and ATP), phosphate group, and a nitrogenous base • 5 nitrogenous bases: adenine (A), thymine (T – only in DNA), guanine (G), cytosine (C), and uracil (U – only in RNA)

23. 5.7 Nucleotides and Nucleic Acids • Nucleic Acids:blueprints for proteins (and life) • Two types: deoxyribonucleic acid (DNA) & ribonucleic acid (RNA) • DNA – the genetic information inherited from parents that controls the life of the cell and organism

24. Happy Halloween!!!!!!!

25. Yippee! It is time to study!