BIO311C FINAL EXAM QUESTIONS AND ANSWERS A+ GRADED
What is the biological hierarchy? Levels and examples.
1. Atoms = C,H,O
2. Molecule = amino acid, sugars
3. Macromolecules = proteins, lipids
4. Parts of cells = membrane, nuclei
5. Cell = bacteria, yeast, skin cell
6. Tissue = epithelial tissue, bone
7. Organ = brain, heart
8. Organ System = immune system
9. Organism = human
10. Population = all individuals of a single species
11.. Ecosystem = collection of populations
12. Biomes = desert, forest
13. Biosphere = Living crust of the earth
Covalent Bonds (polar and non polar)
two atoms which share a pair of electrons
polar = two atoms share electrons unequally (example: H2O)
non polar = two atoms which share electrons equally (example: H2)
Ionic Bonds
bonding due to attraction of positive and negative charges
(weaker than covalent bonds) (example: NaCl)
H-Bonding
electrostatic attraction between polar molecules that occurs when a hydrogen (H) atom
bound to a highly electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F)
experiences attraction to some other nearby highly electronegative atom (example:
NH3)
Van der Waals Interactions
weakest bond with temporary changes (example: lipids)
Hydrophilic Interactions
(water loving) substances are normally polar, charged molecules, soluble in water
Hydrophobic Interactions
(water fearing) normally non polar, lipid-soluble molecules that are excluded from
aqueous solutions by hydrogen bonding among polar molecules
Which part of the atom mainly determines how the atom behaves chemically?
A. proton
B. electron
C. neutron
D. meson
E. gluon
B
Which of the following is the correct ranking of the three bonds and interactions
in order from highest to lowest in terms of their bond strength between two side
,chains of a protein in their tertiary structure?
I. Disulfide bond between two cystines
II. Hydrophobic interactions between two leucines
III. H-bonding in water
I, III, II
Which of the following molecules is most polar?
A. CO2
B. CH4
C. CH3OH
D. C2H6
E. O2
C
When water freezes to form ice, the ___ connect the water molecules.
A. covalent bonds
B. ionic bonds
C. H-bonds
D. van der waals forces
E. hydrophobic interactions
C
When Magnesium and chlorines with two electrons and seven electrons
respectively in their valence shells interact, they will form ___.
A. covalent bonds
B. ionic bonds
C. H-bonds
D. van der waals forces
E. hydrophobic interactions
B
Which bonds will break when water evaporates?
A. covalent bonds
B. ionic bonds
C. H-bonds
D. van der waals forces
E. hydrophobic interactions
C
Which of the following properties of water is the most essential to support life?
A. Ability to maintain pH
B. H-bonding property
C. High specific temperature
D. Good solvent for both polar and non-polar substances E. Medium and a
reactant for biochemical reactions
E
A solution contains 0.001 moles of hydroxide ions [OH-] per liter. Which of the
following best describes this solution?
A. Slightly acidic
B. Slightly basic
C. Strongly acidic
, D. Strongly basic
E. Neutral in pH
D
How will you make a 200 ml solution of 5 mM sucrose from a 100 mM sucrose
solution?
A. Mix 20 ml of the 100 mM sucrose and 180 ml of water. B. Mix 10 ml of the 100
mM sucrose and 190 ml of water. C. Mix 1 ml of the 100 mM sucrose and 199 ml of
water.
D.Mix 2 ml of the 100 mM sucrose and 198 ml of water.
E. Mix 50 ml of the 100 mM sucrose and 150 ml of water.
B
Carbonic acid and sodium bicarbonate act as buffers in the blood. When a small
amount of acid is added to this blood, the H+ ions are used up as they combine
with the bicarbonate ions. When this happens, the pH of the blood __________.
A. becomes basic.
B. becomes acidic.
C. does not change much.
D. is drastically changed
E. will decrease significantly
C
Of the following compounds containing 12C, 1H and/or 16O, which one would
have the greatest number of molecules in a sample of 2 grams each?
A. CH4
B. CO2
C. CH3OH
D. C2H5OH
E. C6H12O6
A
How much NaOH (MW = 40) is needed (in grams) to make a 200 ml of 0.5 M
solution?
4 grams
How much volume (in ml) of 10% SDS is needed to make 500 ml of 1% SDS?
50 mL
Functional Groups
atoms or groups of atoms covalently bonded to the carbon skeleton
Hydroxyl Group:
formula, functional group of, polar or non polar, soluble?
-OH, alcohols and carbohydrates, polar, easily soluble in water
Carbonyl Group:
-C=O
Carboxyl Group:
-COOH
Amino Group:
-NH2
Sulfhydryl Group:
-SH
What is the biological hierarchy? Levels and examples.
1. Atoms = C,H,O
2. Molecule = amino acid, sugars
3. Macromolecules = proteins, lipids
4. Parts of cells = membrane, nuclei
5. Cell = bacteria, yeast, skin cell
6. Tissue = epithelial tissue, bone
7. Organ = brain, heart
8. Organ System = immune system
9. Organism = human
10. Population = all individuals of a single species
11.. Ecosystem = collection of populations
12. Biomes = desert, forest
13. Biosphere = Living crust of the earth
Covalent Bonds (polar and non polar)
two atoms which share a pair of electrons
polar = two atoms share electrons unequally (example: H2O)
non polar = two atoms which share electrons equally (example: H2)
Ionic Bonds
bonding due to attraction of positive and negative charges
(weaker than covalent bonds) (example: NaCl)
H-Bonding
electrostatic attraction between polar molecules that occurs when a hydrogen (H) atom
bound to a highly electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F)
experiences attraction to some other nearby highly electronegative atom (example:
NH3)
Van der Waals Interactions
weakest bond with temporary changes (example: lipids)
Hydrophilic Interactions
(water loving) substances are normally polar, charged molecules, soluble in water
Hydrophobic Interactions
(water fearing) normally non polar, lipid-soluble molecules that are excluded from
aqueous solutions by hydrogen bonding among polar molecules
Which part of the atom mainly determines how the atom behaves chemically?
A. proton
B. electron
C. neutron
D. meson
E. gluon
B
Which of the following is the correct ranking of the three bonds and interactions
in order from highest to lowest in terms of their bond strength between two side
,chains of a protein in their tertiary structure?
I. Disulfide bond between two cystines
II. Hydrophobic interactions between two leucines
III. H-bonding in water
I, III, II
Which of the following molecules is most polar?
A. CO2
B. CH4
C. CH3OH
D. C2H6
E. O2
C
When water freezes to form ice, the ___ connect the water molecules.
A. covalent bonds
B. ionic bonds
C. H-bonds
D. van der waals forces
E. hydrophobic interactions
C
When Magnesium and chlorines with two electrons and seven electrons
respectively in their valence shells interact, they will form ___.
A. covalent bonds
B. ionic bonds
C. H-bonds
D. van der waals forces
E. hydrophobic interactions
B
Which bonds will break when water evaporates?
A. covalent bonds
B. ionic bonds
C. H-bonds
D. van der waals forces
E. hydrophobic interactions
C
Which of the following properties of water is the most essential to support life?
A. Ability to maintain pH
B. H-bonding property
C. High specific temperature
D. Good solvent for both polar and non-polar substances E. Medium and a
reactant for biochemical reactions
E
A solution contains 0.001 moles of hydroxide ions [OH-] per liter. Which of the
following best describes this solution?
A. Slightly acidic
B. Slightly basic
C. Strongly acidic
, D. Strongly basic
E. Neutral in pH
D
How will you make a 200 ml solution of 5 mM sucrose from a 100 mM sucrose
solution?
A. Mix 20 ml of the 100 mM sucrose and 180 ml of water. B. Mix 10 ml of the 100
mM sucrose and 190 ml of water. C. Mix 1 ml of the 100 mM sucrose and 199 ml of
water.
D.Mix 2 ml of the 100 mM sucrose and 198 ml of water.
E. Mix 50 ml of the 100 mM sucrose and 150 ml of water.
B
Carbonic acid and sodium bicarbonate act as buffers in the blood. When a small
amount of acid is added to this blood, the H+ ions are used up as they combine
with the bicarbonate ions. When this happens, the pH of the blood __________.
A. becomes basic.
B. becomes acidic.
C. does not change much.
D. is drastically changed
E. will decrease significantly
C
Of the following compounds containing 12C, 1H and/or 16O, which one would
have the greatest number of molecules in a sample of 2 grams each?
A. CH4
B. CO2
C. CH3OH
D. C2H5OH
E. C6H12O6
A
How much NaOH (MW = 40) is needed (in grams) to make a 200 ml of 0.5 M
solution?
4 grams
How much volume (in ml) of 10% SDS is needed to make 500 ml of 1% SDS?
50 mL
Functional Groups
atoms or groups of atoms covalently bonded to the carbon skeleton
Hydroxyl Group:
formula, functional group of, polar or non polar, soluble?
-OH, alcohols and carbohydrates, polar, easily soluble in water
Carbonyl Group:
-C=O
Carboxyl Group:
-COOH
Amino Group:
-NH2
Sulfhydryl Group:
-SH
