Principles of Biology - Exam 1
1/1H and 3/1H have... a) different chemical properties because they have different atomic numbers b) the same chemical properties because they have the same number of valence electrons c) different chemical properties because they differ in their number of protons and electrons d) the same chemical properties because they have the same atomic mass e) the same chemical properties because they have the same number of protons, neutrons, and electrons
b) the same chemical properties because they have the same number of valence electrons
each phosphodiester linkage in dna or rna includes a phosphate joined by covalent bonds to... a) two bases b) two sugars c) two additional phosphates d) a sugar, a base, and a phosphate e) a sugar and a base
b) two sugars
fatty acids in phospholipids and triacylglycerols interact with one another by... a) disulfide bridges b) van der waals interactions c) covalent bonds d) hydrogen bonds e) fatty acids do not interact with each other
b) van der waals interactions
a monosaccharide designated as an aldehyde sugar contains... a) a terminal carboxyl group b) an internal carboxyl group c) a terminal carbonyl group d) an internal carbonyl group e) a terminal carboxyl group and an internal carbonyl group
c) a terminal carbonyl group
cellular respiration
is carried on by both autotrophs and heterotrophs
carbon is well suited to be the backbone of organic molecules because...
it can bond to atoms of a large number of other elements
a solution at pH 7 is considered neutral because...
its hydrogen ion concentration is equal to its hydroxide ion concentration
dna
makes up genes
darwin suggested that evolution takes place by...
natural selection
ideally, an experimental group differs from a control group...
only with respect to the variable being studied
a solution with a pH of 2 has a hydrogen ion concentration that is _____ the hydrogen ion concentration of a solution with a pH of 4.
100 times
in a redox reaction... a) energy is transferred from a reducing agent to an oxidizing agent b) a reducing agent becomes oxidized as it accepts an electron c) an oxidizing agent accepts a proton d) a reducing agent donates a proton e) the electrons in an atom move from its valence shell to a shell closer to its nucleus
a) energy is transferred from a reducing agent to an oxidizing agent
structural polysaccharides typically... a) have extensive hydrogen bonding between adjacent molecules b) are much more hydrophilic than storage polysaccharides c) have much stronger covalent bonds than storage polysaccharides d) consist of alternating alpha-glucose and beta-glucose subunits e) form helical structures in the cell
a) have extensive hydrogen bonding between adjacent molecules
which of the following facts allows you to determine that arom A and atom B are isotopes of the same element? a) they each have 6 protons b) they each have 4 neutrons c) the sum of the electrons and neutrons in each is 14 d) they each have 4 valence electrons e) they each have an atomic mass of 14
a) they each have 6 protons
cells
are the building blocks of living organisms
which of the following elements is mismatched with its properties or functions? a) carbon - forms the backbone of organic compounds b) nitrogen - component of proteins c) hydrogen - very electronegative d) oxygen - can participate in hydrogen bonding e) all of the above are correctly matched
c) hydrogen - very electronegative
the orbitals composing an atom's valence electron shell... a) are arranged as concentric spheres b) contain the atom's least energetic electrons c) may change shape when covalent bonds are formed d) never contain more than 1 electron each e) more than one of the preceding is correct
c) may change shape when covalent bonds are formed
which of the following levels of protein structure may be affected by hydrogen bonding? a) primary and secondary b) primary and tertiary c) secondary, tertiary, and quaternary d) primary, secondary, and tertiary e) primary, secondary, tertiary, and quaternary
c) secondary, tertiary, and quaternary
what is the correct sequence of levels of biological organization?
chemical, cell, tissue, organ, organ system
the synthetic process by which monomers are covalently linked is...
condensation
which of the following bonds and properties are correctly matched? a) ionic bonds - are strong only if the participating ions are hydrated b) hydrogen bonds - are responsible for bonding oxygen and hydrogen to form a single water molecule c) polar covalent bonds - can occur between two atoms of the same element d) covalent bonds - may be single, double, or triple e) hydrogen bonds - are stronger than covalent bonds
d) covalent bonds - may be single, double, or triple
32/15P, a radioactive form of phosphorus, has... a) an atomic number of 32 b) an atomic mass of 15 c) an atomic mass of 47 d) 32 electrons e) 17 neutrons
e) 17 neutrons
which of the following cannot function as a buffer? a) phosphoric acid, a weak acid b) sodium hydroxide, a strong base c) sodium chloride, a salt that ionizes completely d) a & c e) b & c
e) b & c
which of the following statements if true? a) the number of individual particles contained in one mole varies depending on the substance b) avogadro's number is the number of particles contained in one mole of a substance c) avogadro's number is 10^23 particles d) one mole of 12C has a mass of 12 g e) b & d
e) b & d
which of the following associations between R groups are the strongest? a) hydrophobic interactions b) hydrogen bonds c) ionic bonds d) peptide bonds e) disulfide bridges
e) disulfide bridges
which of the following is a nonpolar molecule? a) water, H2O b) ammonia, NH3 c) methane, CH4 d) ethane, C2H6 e) more than one of the preceding is correct
e) more than one of the preceding is correct
fungi are assigned to domain...
eukarya
the scientific name for corn is Zea mays. Zea is the...
genus
saturated fatty acids are so named because they are saturated with...
hydrogen
water has a high specific heat because...
hydrogen bonds must be broken to raise its temperature