Molecular & Cellular Biology – Clep
Test Questions and Correct Answers.
Electronegativity - Answer ability to attract electrons
Isotopes - Answer variants of a particular chemical element
protons/electrons stay the same, neutrons vary
carbon 14 has 6 protons, 8 neutrons (6+8=14), 6 electrons
ionic Bonds - Answer electrons transferred (NaCl), high electronegativity between atoms
covalent Bonds - Answer electrons shared
hydrogen Bonds - Answer weak bonds between polar molecules
nonpolar covalent Bonds - Answer electrons shared equally (O2, hydrophobic)
polar covalent Bonds - Answer electrons shared unequally (H2O, hydrophilic)
pH - Answer logarithmic scale (tenfold)
acids (acidic) - pH < 7, release hydrogen ions (H+) in water
bases (alkaline) - pH > 7, release hydroxide ions (OH-) in water
Properties of water - Answer solvent - distinct postive/negative regions (dipolar),
separates polar substances into ions
cohesive - molecules stick together (hydrogen bonds), high surface tension
adhesive - molecules stick to other substances, capillary action
heat capacity - resists temperature change (stable)
ice floats - expands as freezes, less dense
Functional groups - Answer hydroxyl -OH - polar (ethanol, glycerol, sugars)
carboxyl -COOH - polar (acetic acid, amino acids, fatty acids, sugars)
amino -NH2 - polar (amino acids)
phosphate -PO3 - polar (DNA, ATP, phospholipids)
carbonyl -CO - polar (acetone, sugars)
,carbonyl -COH - polar (formaldehyde, sugars)
methyl -CH3 - nonpolar (fatty acids, oils, waxes)
Carbohydrates - Answer carbon, hydrogen, oxygen (1:2:1)
monosaccharides - Answer energy source for cells (glucose, fructose), linear or ring structure
isomer - Answer common molecular formula, molecular structure differ
disaccharides - Answer (maltose, sucrose, lactose)
glycosidic linkage - Answer hydrogen from one sugar combines with the hydroxyl group of
another
hydrolysis - Answer add H2O to break bonds
polysaccharides - Answer polymer, glucose storage or structure
starch (α-glucose) - Answer plant storage (plastids)
glycogen (α-glucose) - Answer animal storage (liver/muscle cells)
cellulose (β-glucose) - Answer - plant structure (cell walls)
chitin (β-glucose) - Answer fungus/arthropod structure
Lipids - Answer carbon, hydrogen, oxygen
cell membrane structure, insulation, energy storage
triglycerides - Answer 3 fatty acids (hydrocarbons + carboxyl group) + glycerol
ester linkage - Answer between glycerol/fatty acids, removal of 3 water molecules
dehydration - Answer saturated - single covalent bonds between each pair of carbon atoms
unsaturated - 1 double covalent bond
, polyunsaturated - 2 or more double covalent bonds
phospholipids - Answer 2 fatty acid tails (hydrophobic) + 1 negatively charged phosphate
head
steroids - Answer 4 linked carbon rings (cholesterol, vitamin D, sex hormones)
Proteins - Answer carbon, hydrogen, oxygen, nitrogen
amino acids (20) - Answer building blocks (amino group + carboxyl group + H + R group/side
chain)
alanine, arginine, cysteine, glutamine, glycine, leucine, taurine, tyrosine, etc
peptide bond - Answer between carboxyl group/amino group (dehydration), forms dipeptide
polypeptide - Answer covalently linked chain of amino acids, folds into 3D structure (protein)
structure
Types Of Proteins - Answer primary - sequence of amino acids, not affected by denaturation
secondary - 3D shape from chain backbone, α-helices/β-sheets (fibrous proteins)
tertiary - α-helices/β-sheets pack into compact shapes (globular proteins)
disulfide bond - bridge when sulfur in cysteine bonds to sulfur in another
cysteine function - Answer structure (keratin, collagen, silk)
storage (casein, ovalbumin)
transport (hemoglobin)
defensive (antibodies)
enzymes
cysteine - Answer quaternary - noncovalent association of multiple proteins (hemoglobin)
Nucleic acids - Answer carbon, hydrogen, oxygen, nitrogen, phosphorus
nucleotides - Answer building blocks (purines, pyrimidines)
DNA - Answer deoxyribose (5C sugar) + nitrogen base + phosphate group, double strand
Test Questions and Correct Answers.
Electronegativity - Answer ability to attract electrons
Isotopes - Answer variants of a particular chemical element
protons/electrons stay the same, neutrons vary
carbon 14 has 6 protons, 8 neutrons (6+8=14), 6 electrons
ionic Bonds - Answer electrons transferred (NaCl), high electronegativity between atoms
covalent Bonds - Answer electrons shared
hydrogen Bonds - Answer weak bonds between polar molecules
nonpolar covalent Bonds - Answer electrons shared equally (O2, hydrophobic)
polar covalent Bonds - Answer electrons shared unequally (H2O, hydrophilic)
pH - Answer logarithmic scale (tenfold)
acids (acidic) - pH < 7, release hydrogen ions (H+) in water
bases (alkaline) - pH > 7, release hydroxide ions (OH-) in water
Properties of water - Answer solvent - distinct postive/negative regions (dipolar),
separates polar substances into ions
cohesive - molecules stick together (hydrogen bonds), high surface tension
adhesive - molecules stick to other substances, capillary action
heat capacity - resists temperature change (stable)
ice floats - expands as freezes, less dense
Functional groups - Answer hydroxyl -OH - polar (ethanol, glycerol, sugars)
carboxyl -COOH - polar (acetic acid, amino acids, fatty acids, sugars)
amino -NH2 - polar (amino acids)
phosphate -PO3 - polar (DNA, ATP, phospholipids)
carbonyl -CO - polar (acetone, sugars)
,carbonyl -COH - polar (formaldehyde, sugars)
methyl -CH3 - nonpolar (fatty acids, oils, waxes)
Carbohydrates - Answer carbon, hydrogen, oxygen (1:2:1)
monosaccharides - Answer energy source for cells (glucose, fructose), linear or ring structure
isomer - Answer common molecular formula, molecular structure differ
disaccharides - Answer (maltose, sucrose, lactose)
glycosidic linkage - Answer hydrogen from one sugar combines with the hydroxyl group of
another
hydrolysis - Answer add H2O to break bonds
polysaccharides - Answer polymer, glucose storage or structure
starch (α-glucose) - Answer plant storage (plastids)
glycogen (α-glucose) - Answer animal storage (liver/muscle cells)
cellulose (β-glucose) - Answer - plant structure (cell walls)
chitin (β-glucose) - Answer fungus/arthropod structure
Lipids - Answer carbon, hydrogen, oxygen
cell membrane structure, insulation, energy storage
triglycerides - Answer 3 fatty acids (hydrocarbons + carboxyl group) + glycerol
ester linkage - Answer between glycerol/fatty acids, removal of 3 water molecules
dehydration - Answer saturated - single covalent bonds between each pair of carbon atoms
unsaturated - 1 double covalent bond
, polyunsaturated - 2 or more double covalent bonds
phospholipids - Answer 2 fatty acid tails (hydrophobic) + 1 negatively charged phosphate
head
steroids - Answer 4 linked carbon rings (cholesterol, vitamin D, sex hormones)
Proteins - Answer carbon, hydrogen, oxygen, nitrogen
amino acids (20) - Answer building blocks (amino group + carboxyl group + H + R group/side
chain)
alanine, arginine, cysteine, glutamine, glycine, leucine, taurine, tyrosine, etc
peptide bond - Answer between carboxyl group/amino group (dehydration), forms dipeptide
polypeptide - Answer covalently linked chain of amino acids, folds into 3D structure (protein)
structure
Types Of Proteins - Answer primary - sequence of amino acids, not affected by denaturation
secondary - 3D shape from chain backbone, α-helices/β-sheets (fibrous proteins)
tertiary - α-helices/β-sheets pack into compact shapes (globular proteins)
disulfide bond - bridge when sulfur in cysteine bonds to sulfur in another
cysteine function - Answer structure (keratin, collagen, silk)
storage (casein, ovalbumin)
transport (hemoglobin)
defensive (antibodies)
enzymes
cysteine - Answer quaternary - noncovalent association of multiple proteins (hemoglobin)
Nucleic acids - Answer carbon, hydrogen, oxygen, nitrogen, phosphorus
nucleotides - Answer building blocks (purines, pyrimidines)
DNA - Answer deoxyribose (5C sugar) + nitrogen base + phosphate group, double strand
