Presentation on theme: "Chemistry & life Biology, 21-25 January 2011 Donald Winslow Readings: Sylvia S. Mader 2011 Inquiry into Life, 13th ed., McGraw-Hill, NY. Ch. 1 pp 1-9;"— Presentation transcript:
Chemistry & life Biology, January 2011 Donald Winslow Readings: Sylvia S. Mader 2011 Inquiry into Life, 13th ed., McGraw-Hill, NY. Ch. 1 pp 1-9; Ch. 2 pp 20-35, 37-41
Objectives for basic chemistry Define “atom” & “element” & give examples. Define “subatomic particle” & give examples. Describe different types of chemical bonds. Describe & give examples of acids & bases. Describe & give examples of important buffers.
Objective for biochemistry Define organic molecules & explain the importance of carbon. Describe the structure & function of carbohydrates, lipids, proteins, and nucleic acids. Give examples of carbohydrates, lipids, proteins, and nucleic acids. Describe dehydration synthesis & hydrolysis.
Matter & energy Matter –Composed of particles, has mass Energy –The ability to do work, involves forces that affect position & movement of particles. –Kinetic energy, potential energy, heat, light, electromagnetic radiation.
Subatomic particles Atomic nucleus composed of protons & neutrons; electrons orbit nucleus. Protons –Positive (+) charge, ~1 atomic mass unit Electrons –Electric (-) charge, ~0 atomic mass units –Potential energy of electron increases with increasing distance from nucleus. Neutrons –No charge, ~1 atomic mass unit
Elements & atoms Atomic symbols –C, H, N, O, P, S, etc. Atomic numbers –Number of protons in nucleus Periodic table of the elements Isotopes – 12 C & 14 C, radiation
Atoms can be combined to form molecules. Chemical reactions result in exchange of atoms between molecules, synthesis of large molecules from small molecules, or division of large molecules into small molecules.
Elements & compounds An element contains only one kind of atom. –Examples: Au, O 2 A compound contains multiple kinds of atoms. –Examples: H 2 O, CO 2
Chemical bonds Ionic bonds –Relation to salts Covalent bonds Polar covalent bonds –Hydrogen bonds
Properties of water High heat capacity, high heat of vaporization Solvent Cohesion & adhesion Ice is less dense than water Hydrogen ion concentration is measured by pH
Acids, bases, & buffers An acidic solution has a high H + concentration & therefore a low pH. –vinegar, citric acid, ascorbic acid, HCl, H 2 SO 4 A basic (alkaline) solution has a low H + concentration & therefore a high pH. –sodium bicarbonate (NaHCO 3 ), antacid, NaOH A buffer solution contains a compound that maintains the pH within a narrow range by binding excess H + and OH - ions. –Examples: carbonic acid (H 2 CO 3 ), NaHCO 3
Lipids Variable structure –Lots of H & C; not much O or N –Not water soluble Functions in energy storage, membranes, chemical messengers, etc. Fatty acids, phospholipids, steroids, cholesterol, waxes, oils
Carbohydrates Polysaccharides are polymers of monosaccharides (monomeric sugars). Function in energy storage & transfer, structural features such as plant cell walls Examples: glucose, fructose, sucrose (table sugar), lactose, starch, glycogen
Proteins Proteins are polypeptides, often modified to form complex shapes. –A polypeptide is a polymer of amino acids, connected by peptide bonds. Function as enzymes (catalyzing chemical reactions), structural proteins, hormones, antibodies, etc. Examples: amylase, keratin, insulin
Nucleic acids Nucleic acids are polymers of nucleotides. Function in heredity; direct cellular metabolism, development, etc. Examples: deoxyribonucleic acid (DNA), ribonucleic acid (RNA)
Molecular shape is important to biological function
Hydrolysis & dehydration synthesis Hydrolysis –Splits polymer into smaller molecules, using a water molecule. Dehydration synthesis –Builds polymer from two smaller molecules, releasing water.
Properties of living things Growth, development, reproduction Need energy & materials for metabolism Composed of cells Organized Communication of information Adaptation Genes direct development, etc.
Biological hierarchy Cell Tissue Organ Organ system Organism Population Community Nine-banded armadillo
Ecological hierarchy Organism Population Community Ecosystem Landscape Biome Biosphere Agricultural corridor within forested landscape in southern Indiana.
Taxonomic hierarchy Domain –Kingdom Phylum –Class »Order » Family » Genus » Species