Presentation on theme: "Organic Molecules * Organic molecules are found in living things (vs. Nonorganic) * Referred to as “macromolecules” -- Carbohydrates -- Lipids -- Proteins."— Presentation transcript:
1 The Macromolecules of Cells: Carbohydrates Lipids Proteins Nucleic Acid
2 Organic Molecules* Organic molecules are found in living things (vs. Nonorganic)* Referred to as “macromolecules”-- Carbohydrates-- Lipids-- Proteins-- Nucleic AcidsThe term “macromolecule” means large molecule.
3 Organic molecules are made of carbon and can form a huge variety of carbon backbone chains.
4 Macromolecules (polymers) are formed from smaller building blocks called monomers. Polymer Monomercarbohydrates monosaccharidesproteins amino acidsnucleic acids nucleotidesLipids “none”
5 Carbohydrates Carbohydrates (sugars) serve as 1) quick energy and short-termenergy storage2) they play a structural role inplants, bacteria, and insects3) many end in the suffix “ose”Carbohydrates also play a role in cell-to-cell recognition. Carbohydrates have the atomic grouping H-C-OH, in which the ratio of H to O atoms is close to 2:1.
6 MonosaccharidesMonosaccharides are sugars that are made up of only one sugar.There are only 3 monosaccharidesGlucose Fructose Galactose
7 Monosaccharide -- one sugar carbohydrate Glucose
8 DisaccharidesDisaccharides are made out of two simple sugars (monosaccharides)Sucrose (table sugar) -- glucose + fructoseMaltose (malt sugar) -- glucose + glucoseLactose (milk sugar) -- galactose + glucose
9 A disaccharide is made from linking two monosaccharides together.
10 ReactionsThe making or breaking of disaccharides uses a molecule of waterCondensation: reaction makes a disaccharide from two monosaccharides and removes a water molecule in the process.Hydrolysis: reaction breaks down a disaccharide by adding a water molecule to satisfy the exposed bonding sites on the two new monosaccharides.
11 Condensation Reaction Water is removed to allow the two sugars to bond together.
12 Hydrolysis ReactionWater is added so O- and OH+ can be added to exposed bonding sites.Satisfies bonds
13 PolysaccharidesLarger sugars are made from linking many glucose molecules Starch Glycogen Cellulose Chitin
14 Examples of Polysaccharides: starch -- (helical structure)energy storage in plantsglycogencellulose -- (unbranched) found in plants for structure. It is not available as an energy source because of structure.Chitin – found in the exoskeleton of insects andcrustaceans(highly branched)quick energy for animalsStarch and glycogen are the storage forms of glucose in plants and animals, respectively. Cellulose is found in plant cell walls. In cellulose, the glucose chains are joined differently than in glycogen or starch; human digestive enzymes cannot break these linkages in cellulose (thus humans derive no energy from eating cellulose).
15 StarchStarch is a storage molecule for plants. It is stored in structures called plastids.Starch is high in energy and is stored energy for the plant.
16 GlycogenGlycogen is a molecule that is used by animals for temporary storage of energy. If not utilized, energy will be stored as fat.
17 ChitinChitin is a polysaccharide found in exoskeletons of crustaceans and insects.
18 CellulosePolysaccharide found in the cell walls of plants. Strong molecule used for structure and support of the plant cell.
19 Lipids do not dissolve in water!!! *Lipids serve as long-term energy stores in cells, form membranes, and serve as hormones and insulation.Lipids do not dissolve in water!!!Main reason why lipids are classified together; all other molecules are soluble in water
20 Structure of Triglycerides Formed from a glycerol molecule andthree fatty acid molecules.
21 Fatty Acid ChainsFatty acids are long chains of carbons with many hydrogens attached. Full of energy since all bonds are potential energy for an organism.Fatty acids may be saturated fatty acids or unsaturated fatty acids.Saturated fatty acids are commonly from animal sources and are solid at room temperature. There are no double covalent bonds between carbons; these molecules are saturated with hydrogen atoms at every position. Saturated fatty acids are associated with increased incidence of cardiovascular disease. Unsaturated fatty acids come from plants sources and are liquid at room temperature. One or more double covalent bonds are found within the carbon chain; these molecules do not have hydrogen atoms at every position along the carbon chain.
22 Saturated vs. Unsaturated “bad for you” “good for you” Saturated Fats have no double bondsFound in tropical oils and animal fatsAll carbons are “saturated” with hydrogens.Straight chainsSolid at room temp.Unsaturated Fats have varying numbers of double bondsCommon in plantsAll carbons are not fully bonded with hydrogensChains are bent at double bondsLiquid at room temp.
23 Some lipids are phospholipids that form cell membranes Some lipids are phospholipids that form cell membranes. These only have two fatty acids chains.Glycerol head is hydrophilic -- loves waterFatty Acid tails are hydrophobic -- hate water
24 Other lipids are steroids -- no fatty acid chains.Examples:Steroids -- Cholesterol (thickens arteries and isimportant in cell membrane)Hormones (estrogen and testosterone)Waxes
25 Proteins Proteins: 1. Serve as structural proteins (cartilage, fingernails, hair, etc.)2. Act as enzymes to speed reactions3. Serve as transport carriers4. Act as antibodies5. Allow materials to cross membranes
26 Proteins are polymers of amino acids. Amino acids have an amino group (–NH2) and a carboxyl group (-COOH). The rest of the molecule is the R group for Remainder of the molecule. It is the R group that varies from one amino acid to the next.
28 Proteins have levels of organization. Primary structure refers to the sequence of amino acids joined by peptide bonds. Secondary structure is any folding or twisting of the chain in space. Tertiary structure comes about when proteins fold into globular shapes. Quaternary structure occurs in proteins that have more than one polypeptide chain twisted together.Extremes in temperature or pH, or chemicals, radiation, and so forth can cause proteins to unfold, thus denaturing them.
29 Protein OrganizationPrimary Structure (1°) -- linear chain of amino acids. Number and sequence of amino acids varies.Secondary Structure(2°) -- shortening of amino acid chain by coiling or pleatingTertiary Structure (3°) -- further folding of chain to create a more compact structureQuaternary Structure (4°) -- only some proteins have this structure which is two or more chains bonded together.
30 Nucleic Acids Nucleotides are monomers of nucleic acids. Examples include Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA).Deoxyribonucleic acid (DNA) serves as genetic material for cells. Ribonucleic acid (RNA) carries the information from DNA to the rest of the cell.