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BSC2085 1st Exam
Chapter 2 (1st Exam)
| Question | Answer |
|---|---|
| Matter | Anything that takes up space and has mass |
| Mass | Amount of material in matter; physical property that determines the weight of an object in Earth’s gravitational field |
| Atom | Smallest stable unit of matter |
| Atoms are composed of these three subatomic particles | Protons, Neutrons, and Electrons |
| Protons | Positive electrical charge |
| Neutrons | Electrically neutral |
| Electrons | Negative electrical charge |
| What is an atom's mass determined by? | The number of protons and neutrons in the nucleus |
| Atoms normally contain equal what? | Protons and electrons |
| Atomic Number | Number of protons in an atom |
| Element | Pure substance composed of atoms of only one kind |
| Isotopes | Atoms of the same element whose nuclei contain the same number of protons, but different numbers of neutrons |
| Mass Number | The total number of protons plus neutrons in the nucleus; is used to designate isotopes. |
| Radioisotopes | Isotopes with unstable nuclei that spontaneously break down and emit subatomic particles of radiation in measurable amounts. |
| Radioactive Decay | Breakdown process of radioisotopes |
| Half-Life | Time required for half of a given amount of the isotope to decay |
| Atomic Weight | Actual mass of an atom; expressed in atomic mass unit |
| Mole | Quantity with a weight in grams equal to that element’s atomic weight |
| How many electrons can the 1st energy level hold? | 2 |
| How many electrons can the 2nd and 3rd energy levels hold each? | 8 |
| Valence Shell | Outermost energy level forming the surface of the atom |
| What are atoms with unfilled energy levels? What do they do? | Unstable and react with other atoms |
| Inert Elements don’t... | Readily participate in chemical processes |
| Chemical Bonds | Hold participating atoms together once the reaction has ended |
| Molecule | Any chemical structure consisting of atoms held together by covalent bonds |
| Compound | Pure chemical substances made up of atoms of two or more different elements, regardless of the type of bond joining them |
| When chemical bonding occurs it results in the creation of what new chemical entities? | Molecules and Compounds |
| Ions | Atoms or molecules that carry an electric charge, either positive or negative; have an unequal number of protons and electrons. |
| How do atoms become ions? | By losing or gaining electrons |
| Cations | Ions with a positive charge |
| Anions | Ions with a negative charge |
| Ionic Bonds | Chemical bonds created by the electrical attraction between anions and cations |
| Electron Donor | Loses one or more electrons and becomes a cation with a positive charge |
| Electron Acceptor | Gains electrons and becomes an anion with a negative charge |
| Covalent Bond | Complete their outer electron shells by sharing electrons with other atoms |
| Nonpolar Covalent Bonds | Covalent bonds involving an equal sharing of electrons |
| Polar Covalent Bonds | Covalent bonds involving an unequal sharing of electrons |
| Free Radical | An ion or molecule that contains unpaired electrons in its outermost energy levels |
| Surface Tension | Act as a barrier that keeps small objects from entering the water |
| What are the three states of matter? | Liquid, Gas, and Solid |
| Liquid | Constant volume but no fixed shape |
| Solid | Maintains volume and shape at ordinary temperatures and pressures |
| Gas | Neither constant volume of fixed shape; will fill any container of any size |
| Molecular Weight | The sum of the atomic weights of its component atoms |
| Metabolism | All the reactions underway in the cells and tissues of the body at any given moment |
| Work | Movement of an object or a change in the physical structure of matter |
| Energy | Capacity to perform work; cannot be destroyed only converted |
| Kinetic Energy | Energy of motion; energy that can be transferred to another object and perform work |
| Potential Energy | Stored energy |
| Three types chemical reactions | Decomposition reaction, synthesis reaction, and exchange reaction |
| Decomposition Reaction | Breaks down the molecule into smaller fragments |
| What is (AB⟶ A+B) an example of? | Decomposition Reactions |
| Hydrolysis | one of the bonds in a complex Molecule is broken and the components of a water molecule are added to the resulting fragments |
| Catabolism | The decomposition of complex molecules within the body’s cells and tissues |
| Synthesis Reaction | The opposite of decomposition, assembles smaller molecules into larger molecules |
| What is A + B⟶AB an example of? | Synthesis Reaction |
| Dehydration Synthesis | The formation of a complex molecule by the removal of a water molecule |
| Anabolism | The synthesis of new molecules within the body’s cells and tissues |
| Exchange Reactions | Parts of the reacting molecules are shuffled around to produce new products |
| Activation Energy | Amount of energy required to start a reaction |
| Enzymes | Promote chemical reactions by lowering the activation energy requirements |
| Exergonic | Reactions that release energy |
| Endergonic | Reactions that absorb energy because more energy is required to begin the reaction |
| Nutrients | Essential elements and molecules normally obtained from the diet |
| Metabolites | All the molecules that can be synthesized or broken down by chemical reactions inside our bodies |
| Inorganic | Generally don’t contain carbon and hydrogen atoms as their primary ingredients |
| Most important inorganic compounds in the body? | Carbon dioxide, oxygen, water, and inorganic acids, bases, and salts |
| Organic | Carbon and hydrogen always for the basis |
| Most important organic compounds in the body? | Carbohydrates, proteins lipids, and nucleic acids |
| Properties of water | Solubility, reactivity, high heat capacity, lubrication |
| Ionization | Ionic bonds are broken down as the individual ions |
| Electrolytes | Soluble inorganic molecules whose ions will conduct an electrical current in solution |
| Hydrophilic Compounds | Molecules that interact readily with water molecules |
| Hydrophobic Compounds | Molecules that do not interact readily with water molecules |
| Colloids | Solution containing dispersed proteins and other large molecules; particles remain in solution indefinitely |
| Suspension | Contains large particles in solution; if undisturbed, these particles will settle out of solution due to the force of gravity |
| More ions means ____ pH, less ions means _____ pH | Lower, higher |
| pH scales range from... | 0-14 |
| Neutral | pH of 7 |
| Acidic | pH below 7 |
| Base | pH above 7 |
| pH of blood | 7.35-7.45 |
| pH of stomach acid | 1 |
| Acid | Any solution that dissociates in solution and releases hydrogen ions, thereby lowering the pH |
| Base | A solute that removes hydrogen ions from a solution and thereby acts as a protein acceptor |
| Salt | An ionic compound containing any cation except a hydrogen ion, and any anion except a hydroxide ion. |
| Buffers | Compounds that stabilize the pH of a solution by removing or replacing hydrogen ions |
| Carbohydrates | An organic compound containing carbon, hydrogen and oxygen in a 1:2:1 ratio |
| Monosaccharides | Simple sugar; contains 3 to 7 carbon atoms |
| Name 2 Monosaccharides | Glucose and Fructose |
| Disaccharides | Two monosaccharides joined together |
| Name a disaccharides | Sucrose |
| Polysaccharides | Disaccharides with additional monosaccharides |
| Name 2 Polysaccharides | Cellulose and Glycogen |
| Lipid | Contain a carbon to hydrogen ratio of 1:2 |
| Five classes of lipids | Fatty acids,Eicosanoids,Glycerides, Steroids, and Phospholipids and Glycolipids |
| Fatty Acids | Long carbon chains with hydrogen atoms attached |
| Eicosanoids | Lipids derived from arachidonic acid, a fatty acid that must be absorbed in the diet because it cannot be synthesized by the body |
| Name two classes of eicosanoids | leukotrienes and prostaglandins |
| Glycerides | Individual fatty acids that can be attached to a modified simple sugar, glycerol |
| Triglycerides (glycerol + three fatty acids) have three functions | Energy source, insulation, and protection |
| Steroid | Large lipid molecules that share a distinctive carbon framework |
| Proteins | Chains of amino acids; most abundant organic compounds |
| Essential functions of proteins | Support, movement, transport, buffering, metabolic regulation, coordination and control, and defense |
| Amino Acid | Long chain of organic molecules |
| A typical protein has ____ amino acids | 100 |
| Each amino acid consists of... | A central carbon atom A hydrogen atom An amino group A carboxyl group An R Group |
| Peptide Bond | A covalent bond between the carboxyl group of one amino acid and the amino group of another |
| Peptides | Molecules consisting of amino acids held together by a peptide bond |
| 4 levels of structural complexity | Primary Structure-length of a single polypeptide Secondary Structure-simple spiral Tertiary Structure-coiling and folding Quaternary Structure |
| 2 general structural classes on the basis of their overall shape and properties | Fibrous Protein and Globular Protein |
| Fibrous Protein | Form extended sheets or strands; usually the product of secondary structure |
| Globular Protein | Compact, generally rounded; product of its tertiary structure |
| All enzymes share three basic characteristics | Specificity Saturation Limits Regulation |
| Cofactor | Ion or a molecule that must bind to the enzyme before substances can also bind |
| Nucleic Acids | Large organic molecules composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus |
| 2 classes of nucleic acid molecules | DNA and RNA |
| Nucleotides | Individual subunits of nucleic acids. |
| Each nucleotide has these three parts | Pentose Phosphate group Nitrogenous base |
| 5 nitrogenous bases exist in nucleic acids | Adenine, guanine, cytosine, thymine, and uracil |
| Both RNA and DNA have these three nitrogenous bases | Adenine, guanine, and cytosine |
| RNA has this nitrogenouse base | Uracil |
| DNA has this nitrogenouse base | Thymine |