The Building Blocks of Life

Organic MoleculesChapter 6

Organic Molecules• All organisms are composed of

organic molecules which contain carbon.

• Organic molecules are made of smaller units that bond to form larger molecules.

• These bonds result in a variety of important organic compounds that can be in the shape of straight chains, branched chains, and rings.

Organic Molecules

• Monomers: small molecule that can bond or chemically combine with other monomers

• Polymers: molecules made from repeating units of monomers

Organic Molecules• Energy is stored in the bonds of

organic molecules.

• The amount of energy will vary from molecule to molecule, therefore not all organic molecules have the same amount of energy available for use.

• The energy stored in organic molecules determines its caloric value.

• Proteins

• Carbohydrates

• Fats and Lipids

• Nucleic Acids

Organic Molecules

Proteins• Made of small chains of amino acids.

• Amino acids are composed of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.

• There are 20 different amino acids.

• Proteins are made of different combinations of all 20 different amino acids.

• A protein’s primary structure is determined by the number and order of amino acids in a chain.

Proteins

http://www.gbiosciences.com/EducationalProducts/Protein-Structure-Analysis.aspx

Proteins• Make up about 15% of total body

mass

• Involved in nearly every function of your body.

• Cells contain proteins that provide structural support, transport substances, communicate signals, speed up chemical reactions, and control cell growth.

Proteins

• As a source of energy, proteins have the same caloric value per gram as carbohydrates.

• Proteins can function as a source of energy only if there is a shortage of carbohydrates or lipids.

Proteins

• Protein structure is related to its function.

• Structural Proteins: support

• Transport Proteins: transport substances

• Hormone Proteins: coordinate body activities

• Contractile Proteins: help control movement

• Enzymes: speed up chemical reactions

Carbohydrates• Composed of carbon, hydrogen, and

oxygen.

• Sugars and starches.

• Basic carbohydrates are monosaccharides (simple sugars).

• Monosaccharides can be linked to form disaccharides which can then be linked to form polysaccharides.

• Ex) Glucose, Sucrose, Glycogen

Carbohydrates

Glucose

SucroseGlycogen

Carbohydrates

• Main energy source for the cell.

• The caloric value of carbohydrates is dependent on the number of carbon-hydrogen bonds.

• Cellulose in plants is used as a structural material.

Lipids• Made mostly of carbon and hydrogen.

• Fats, oils, and waxes.

• Composed of fatty acids, glycerol, and other components.

• Saturated: fatty acid tails contain single bonds between carbon atoms

• Unsaturated: fatty acid tails have at least one double bond between carbon atoms

Lipids

http://www.chemistrypictures.org/v/lipids/1Lipids.jpg.html

Lipids

• Triglycerides: fat if solid at room temperature and oil is liquid at room temperature

• Phospholipids: structure and function of cell membrane

• Steroids: cholesterol and hormones

Lipids• Primary function is to store energy.

• Important when carbohydrates are scarce.

• Fats contain more energy per gram than carbohydrates and proteins therefore they have a greater caloric value.

• Provide long-term energy storage, cushion vital organs, and insulation for the body.

• Major component of cell membranes.

Nucleic Acids

• Complex macromolecules that store and transmit genetic information.

• Made of smaller repeating subunits called nucleotides.

• Composed of carbon, oxygen, phosphorus, and hydrogen.

Nucleic Acids