General Biology 1 Chapters 1 14 Outlines CHAPTER 1 1 1 How to define life Protists unicellular eukaryotes larger more complex than bacteria ex Paramecium Atoms are the basic units of matter and cells are the basic units of structure and function of all living things Atom Molecule Tissue Organ Organ System Organism Species Species Population Community Ecosystem Biosphere Population all the members of one species in an area Energy is the capacity to do work metabolism all chemical reactions in a cell Homeostasis is maintained through chemicals behavior the nervous and endocrine systems 1 2 Evolution the unifying concept of biology Taxonomy system of identifying and grouping organisms Species Genus Family Order Class Phylum Kingdom Domain Species interbreeding individuals Domains Bacteria Archaea and Eukarya Bacteria variously adapted to living almost anywhere Archaea can live in aquatic environments that lack oxygen or poor conditions Eukarya protists unicellular and multicellular ex Algae protozoans and water molds plants multicellular photosynthetic organisms fungi help decompose dead organisms animals multicellular organisms that must ingest food Mutations introduce variation among the members of a population 1 3 How the biosphere is organized Ecosystems are characterized by chemical cycling and energy flow With the transfer of energy in the food chain some energy is lost to heat Ecosystems could not exist without constant input of solar energy The two most biologically diverse ecosystems are the tropical rain forests and the coral reefs Biodiversity is the total number and relative abundance of species the variability of their genes and the different ecosystems in which they live Extinction is the death of a species or larger classification category 1 4 The process of science The scientific method is a standard series of steps used in gaining new knowledge widely accepted among scientists Inductive reasoning occurs whenever a person uses creative thinking to combine isolated facts into a cohesive whole Deductive reasoning involves if then logic how to test a hypothesis Observation Hypothesis inductive reasoning Experiment deductive reasoning Data Conclusion Scientific theories are concepts that join together well supported and related hypotheses supported by a broad range of observations experiments and data principles laws The theory of evolution is a unifying concept in biology CHAPTER 2 2 1 Chemical Elements Matter refers to anything that takes up space and has mass An element cannot be broken down into simpler substances with difference properties There are only 92 naturally occurring elements 6 elements basic to life oxygen carbon hydrogen sulfur nitrogen and phosphorous An atom is the smallest part of an element that displays the properties of an element The mass number is the sum of the protons and neutrons because the electrons weigh so little it does not make sense to weigh them Mendeleev created the Periodic Table periods horizontal groups vertical Isotopes are atoms of the same element and number of protons but that differ in the number of neutrons and atomic mass The Geiger counter is an instrument that is commonly used to detect radiation which is used to date objects create images and trace the movement of substances Radioactive isotopes can be used as tracers to detect molecular changes Bohr model electron shells represent energy levels The octet rule states that the outer shell is most stable when it has eight electrons in it outer shell or valence shell atoms with eight electrons already are considered noble gases 2 2 Compounds and molecules Compound two or more elements bonded together Molecule smallest part of a compound that still has the properties of the compound Spontaneous reactions occur freely and always release energy Ions or charged particles form ionic bonds like in NaCl Salts are solid substances that usually separate and exist as individual ions in water Covalent bonds result when two atoms share electrons so each atom forms an octet When sharing of electrons between two atoms is equal it is a nonpolar covalent bond Electronegativity is dependent on the number of protons more proton more electronegativity If one atom is able to attract electrons to a greater degree than the other atom it is the more electronegative atom When electrons are not shared equally it is a polar covalent bond 2 3 Chemistry of water A hydrogen bond is the attraction of slightly positive hydrogen to a slightly negative atom close by Although a hydrogen bond is more easily broken than a covalent bond many hydrogen bonds together are quite strong 1 Water has a high heat capacity A calorie is the amount of heat energy needed to raise the temperature of 1g of water one degree C Water can absorb heat without a great change in temperature 2 Water has a high heat of evaporation Hydrogen bonds must be broken before water boils 3 Water is a universal solvent Molecules that attract water are hydrophilic Nonionized and nonpolar molecules that cannot attract water are said to be hydrophobic 4 Water molecules are cohesive and adhesive Cohesion refers to the ability of water molecules to cling to each other due to hydrogen bonding Adhesion refers to the ability of water molecules to cling to other polar surfaces 5 Water has a high surface tension 6 Frozen water is less dense than liquid water 2 4 Acids and bases Acids are substances that dissociate in water releasing H ions Bases are substances that either take up H ions or release OH ions A buffer is a chemical or a combination of chemicals that keeps pH within normal limits pH of blood 7 4 CHAPTER 3 3 1 Organic molecules Organic molecules are those that contain both carbon and hydrogen always have covalent bonding and are large Inorganic molecules usually contain positive and negative ions usually have ionic bonding and contain small numbers of atoms The carbon chain of an organic molecule is called its skeleton or backbone Functional groups Hydroxyl R OH alcohol ex Ethanol polar present in sugars and amino acids Carbonyl R C H O aldehyde ex Formaldehyde polar present in sugars Carboxyl R C R O ketone ex Acetone polar present in sugars Amino R N H2 amine ex Tryptophan polar basic present in amino acids Sulfhydryl R SH thiol ex Ethanethiol forms disulfide bonds present in amino acids Phosphate R O P O OH OH polar acidic present in nucleotides and phospholipids Organic molecules that have identical molecular formulas but a different