BS 161 exam UPDATED ACTUAL
Questions and CORRECT Answers
Describe how living cells with and without cell walls regulate water balance - CORRECT
ANSWER - Cells without cell walls are immersed in an isotonic environment that
experiences no net water movement.
Cells with cell walls osmoregulate to control water balance The cell wall keeps the cell from
bursting, but cannot keep it from shrinking.
dehyration reaction
vs hydrolysis reaction - CORRECT ANSWER - d-a molecule of water is removed
h-a molecule of water is added
macromolecules - CORRECT ANSWER - -proteins, nucleic acids, carbohydrates,lipids
-monomer=basic unit of macromolecule
-proteins:amino acids
-nucleic acids:nucleotides
-carbohydrate:sacchardies
-lipids:glycerol and fatty acids
Prokaryotic and eukaryotic cells generally have which one of the following
features in common - CORRECT ANSWER - free ribsomes
,how does cholesterol function in the plasma membrane? - CORRECT ANSWER -
maintains fluidity
Which of the following large biological molecules is not composed of repeati
ng monomers? - CORRECT ANSWER - lipids
Which statement is true of translation of a protein that is destined for use in the nucleus? -
CORRECT ANSWER - Translation is completed on a ribosome in the cytoplasm
how do enzymes affect a reaction and why does this happen - CORRECT ANSWER -
Enzymes make reactions proceed more quickly because enzymes lower the activation energy of
the reaction
what is required for the bonding of two amino acid molecules to form a larger molecule? -
CORRECT ANSWER - removal of a water molecule
Proteins digested by trypsin in the stomach are broken down to amino acids in
which type of reaction? - CORRECT ANSWER - hydrolysis
Denaturation disrupts the secondary and tertiary structure of proteins. However, denaturation is
not strong
enough to disrupt which interaction that is relevant to protein structure? - CORRECT
ANSWER - peptide bonds
Which two functional groups are always found in amino acids? - CORRECT ANSWER -
carboxyl and amino
Living organisms are composed primarily of which four elements - CORRECT
ANSWER -ochn
,Describe differences between osmosis, facilitated diffusion, and active transport - CORRECT
ANSWER - Osmosis: The diffusion of water across a selectively permeable membrane.
Facilitated diffusion: The diffusion of polar molecules and ions across a membrane with the aid
of transport proteins
Active transport: The movement of a substance across a cell membrane, with an expenditure of
energy, against its concentration gradient; mediated by specific transport proteins.
Describe the molecular structure of
covalent bond
ionic bond
hydrogen bond
hydrophobic exclusion - CORRECT ANSWER - covalent-two atoms share one or more
pairs of valence electrons
ionic bond-opposite charge attraction
hydrogen bond- sharing a hydrogen between 2 electronegative atoms
hydrophobic exclusion-the tendency of nonpolar molecules to aggregate in water
Describe the relative strength of
covalent bond
ionic bond
hydrogen bond
hydrophobic exclusion - CORRECT ANSWER - covalent bond- triple bonds>double
bonds>single bonds (strongest)
, ionic bond-opposite charges attract (second strongest)
hydrogen bond- positive end of polar is attracted to negative end of FON (third strongest)
hydrophobic- water causes molecules to assume particular shapes(last)
what are cells made of? - CORRECT ANSWER - subatomic particles
atoms to molecules(amino acids) to macromolecules(proteins) to organelles
polar covalent bonds? - CORRECT ANSWER - hydrogen=carbon<nitrogen<oxygen
Describe the atomic level
covalent bond
ionic bond
hydrogen bond
hydrophobic exclusion - CORRECT ANSWER - covalent bond-
covalent bond between two atoms of similar electronegativity is - CORRECT ANSWER -
nonpolar
electronegativity increases
decreases? - CORRECT ANSWER - left to right
down
strength of interaction in a solid solution?
covalent
ionic
Questions and CORRECT Answers
Describe how living cells with and without cell walls regulate water balance - CORRECT
ANSWER - Cells without cell walls are immersed in an isotonic environment that
experiences no net water movement.
Cells with cell walls osmoregulate to control water balance The cell wall keeps the cell from
bursting, but cannot keep it from shrinking.
dehyration reaction
vs hydrolysis reaction - CORRECT ANSWER - d-a molecule of water is removed
h-a molecule of water is added
macromolecules - CORRECT ANSWER - -proteins, nucleic acids, carbohydrates,lipids
-monomer=basic unit of macromolecule
-proteins:amino acids
-nucleic acids:nucleotides
-carbohydrate:sacchardies
-lipids:glycerol and fatty acids
Prokaryotic and eukaryotic cells generally have which one of the following
features in common - CORRECT ANSWER - free ribsomes
,how does cholesterol function in the plasma membrane? - CORRECT ANSWER -
maintains fluidity
Which of the following large biological molecules is not composed of repeati
ng monomers? - CORRECT ANSWER - lipids
Which statement is true of translation of a protein that is destined for use in the nucleus? -
CORRECT ANSWER - Translation is completed on a ribosome in the cytoplasm
how do enzymes affect a reaction and why does this happen - CORRECT ANSWER -
Enzymes make reactions proceed more quickly because enzymes lower the activation energy of
the reaction
what is required for the bonding of two amino acid molecules to form a larger molecule? -
CORRECT ANSWER - removal of a water molecule
Proteins digested by trypsin in the stomach are broken down to amino acids in
which type of reaction? - CORRECT ANSWER - hydrolysis
Denaturation disrupts the secondary and tertiary structure of proteins. However, denaturation is
not strong
enough to disrupt which interaction that is relevant to protein structure? - CORRECT
ANSWER - peptide bonds
Which two functional groups are always found in amino acids? - CORRECT ANSWER -
carboxyl and amino
Living organisms are composed primarily of which four elements - CORRECT
ANSWER -ochn
,Describe differences between osmosis, facilitated diffusion, and active transport - CORRECT
ANSWER - Osmosis: The diffusion of water across a selectively permeable membrane.
Facilitated diffusion: The diffusion of polar molecules and ions across a membrane with the aid
of transport proteins
Active transport: The movement of a substance across a cell membrane, with an expenditure of
energy, against its concentration gradient; mediated by specific transport proteins.
Describe the molecular structure of
covalent bond
ionic bond
hydrogen bond
hydrophobic exclusion - CORRECT ANSWER - covalent-two atoms share one or more
pairs of valence electrons
ionic bond-opposite charge attraction
hydrogen bond- sharing a hydrogen between 2 electronegative atoms
hydrophobic exclusion-the tendency of nonpolar molecules to aggregate in water
Describe the relative strength of
covalent bond
ionic bond
hydrogen bond
hydrophobic exclusion - CORRECT ANSWER - covalent bond- triple bonds>double
bonds>single bonds (strongest)
, ionic bond-opposite charges attract (second strongest)
hydrogen bond- positive end of polar is attracted to negative end of FON (third strongest)
hydrophobic- water causes molecules to assume particular shapes(last)
what are cells made of? - CORRECT ANSWER - subatomic particles
atoms to molecules(amino acids) to macromolecules(proteins) to organelles
polar covalent bonds? - CORRECT ANSWER - hydrogen=carbon<nitrogen<oxygen
Describe the atomic level
covalent bond
ionic bond
hydrogen bond
hydrophobic exclusion - CORRECT ANSWER - covalent bond-
covalent bond between two atoms of similar electronegativity is - CORRECT ANSWER -
nonpolar
electronegativity increases
decreases? - CORRECT ANSWER - left to right
down
strength of interaction in a solid solution?
covalent
ionic
