Final Examination: Anatomy and Physiology Chapters 1-13 Que &Ans

radioactive atoms have unstable - ANS nuclei Atoms are the smallest stable units of __________. - ANS matter The "atomic number" of an atom is determined by the number of __________ it has - ANS protons One mole of any element - ANS has the same number of atoms the nucleus of an atom consists of - ANS protons + neutrons A(n) __________ is a pure substance composed of atoms of only one kind - ANS element Which parts of atoms can interact (react) to form chemical bonds? - ANS valence electrons Atoms of oxygen have a total of 8 electrons. Are these atoms stable, and why or why not? - ANS No, because the atoms have only 6 valence electrons, nut need 8 for stability Carbon atoms have four valence electrons. Are they likely to react with other atoms, and why or why not? - ANS Yes, because they can become more stable by doing so What is an ion? - ANS An atom that has either gained or lost electron(s) When an ionic bond forms, which part(s) of the atoms are directly involved? - ANS The outermost electron shell How do ions form ionic bonds? - ANS Ions of opposite electrical charges are attracted to each other to balance the charges In a covalent bond, - ANS atoms share one to three pairs of electrons Polar covalent bonds, - ANS share electrons unequally A molecule of water is formed by what type of bond? - ANS polar covalent bonds Rank the types of chemical bonds, in order, from strongest to weakest - ANS covalent, ionic, hydrogen What distinguished hydrogen bonds from covalent bonds? - ANS Only hydrogen bonds can form between molecules In an aqueous solution, cations are attracted toward - ANS anions When atoms complete their outer electron shell by sharing electrons, they form - ANS covalent bonds Ionic bonds, such as in sodium chloride, __________. - ANS are formed by the association of ions with opposite charge because ionic bonds are the result of the association of anions and cations. Which pH is more acidic; a pH of 3, a pH of 7, or a pH of 9? - ANS pH of 3 because the lower the number, the greater the hydrogen ion concentration If a substance has a pH that is greater than 7, it is - ANS alkaline or basic A(n) __________ removes hydrogen ions and a(n) __________ releases hydrogen ions. - ANS base; acid In plasma, a typical body fluid, protein floating around would be considered to be which of the following? a) a solvent b) a solute, specifically both a colloid and an electrolyte c) a solute, specifically both a colloid and a nonelectrolyte - ANS b) a solue, specifically both a colloid and an electrolyte Electrolytes are charged particles called ions that are dissolved in body fluids. Which of the following ions would be considered a major anion in the body? a) calcium b) potassium c) sodium d) chloride - ANS d) chloride Which of the following is not a result of hydrogen bonds? a) Two hydrogen atoms join together to form a molecule of hydrogen gas b) Two strands of DNA are linked together taking a shape similar to a ladder c) An anzyme has a unique shape that allows it to bond only with specific molecules d) some hair is straight, some wavy, and some very curly - ANS a) Two hydrogen atoms join together to form a molecule of hydrogen gas Water acts to dissolve molecules in the body. How does water dissolve the salt (NaCl) in your mouth from a salty pretzel? - ANS Water acts as a solvent because the partial negative charge on the oxygen in water attracts sodium, while the partial positive charge on hydrogen attracts chloride. This results in the separation of sodium from chloride, thus breaking the ionic bond. carbohydrates, lipids, nucleic acids and proteins are classified as - ANS organic macromolecules A functional group is best described as reoccurring clusters of - ANS atoms that greatly influence the chemical properties of molecules they are part of carbohydrate molecules - ANS are the body's most readily available source of energy ionic bonds are formed when - ANS an electron or electrons are completely transferred from one atom to another