BIO 105 EXAM 2 COMPREHENSIVE GENETICS
AND CELL DIVISION STUDY GUIDE 2026
◉ Explain why some BONDS are polar and some are nonpolar.
Answer: Polar Bonds-when electrons are unequally shared between
atoms
Non-polar Bonds-electrons more equally shared between atoms
◉ Explain why some MOLECULES are polar and some are nonpolar.
Answer: Polar Molecules-charges of molecules unequally shared (ex.
Water molecule because hydrogen is a positively charged ion and
there's 2 of them, while there's only 1 negatively charged oxygen
molecule)
Non-polar Molecules-share their charges equally (so no
electronegativity)
◉ Give an example of each of the following weak (non-bonding)
interactions and order them according to how strong they are.
Answer: Ion-Dipole (1) - ionic compound mixing with polar
compound ex.table salt dissolving in water
,Dipole-dipole (3) - interactions between polar molecules (ex.
Hydrogen chloride)
H-bonding (special dipole-dipole) (2) - electronegativity is high
enough (ex. H2O)
Dispersion (van der Waals) (4) - weak attractions between
molecules that are close to each other (ex. Hydrogen bonding)
◉ 4 Properties of Water.
Answer: adhesion/cohesion, specific temp, density, solvent
(dissolves polar molecules)
◉ Water Soluble.
Answer: Dissolve in water
◉ Explain hydrophobicity based on polarity.
Answer: Polar molecules have charged ends so they mix with water
(hydrophilic) while non polar molecules don't have charged ends do
they don't mix with water (hydrophobicity)
◉ Explain why hydrophobic molecules cluster together in water.
, Answer: Hydrophobic molecules don't mix with water, since they
don't interact with water, they will be attracted to each other,
creating a bond within each other.
◉ Explain how energy is stored in a chemical bond.
Answer: Chemical energy is stored in the bonds of molecules, when
the bond is broken chemical energy is released or absorbed.
◉ Identify the common functional groups.
Answer: Proteins, lipids, carbohydrates, nucleic acids
◉ Dehydration synthesis.
Answer: build molecules up/build energy
◉ Hydrolysis.
Answer: break molecules down/release energy
◉ Hydrophobicity.
Answer: ability of a substance to repel water
◉ Hydrophilic.
Answer: ability of a substance to mix with water
AND CELL DIVISION STUDY GUIDE 2026
◉ Explain why some BONDS are polar and some are nonpolar.
Answer: Polar Bonds-when electrons are unequally shared between
atoms
Non-polar Bonds-electrons more equally shared between atoms
◉ Explain why some MOLECULES are polar and some are nonpolar.
Answer: Polar Molecules-charges of molecules unequally shared (ex.
Water molecule because hydrogen is a positively charged ion and
there's 2 of them, while there's only 1 negatively charged oxygen
molecule)
Non-polar Molecules-share their charges equally (so no
electronegativity)
◉ Give an example of each of the following weak (non-bonding)
interactions and order them according to how strong they are.
Answer: Ion-Dipole (1) - ionic compound mixing with polar
compound ex.table salt dissolving in water
,Dipole-dipole (3) - interactions between polar molecules (ex.
Hydrogen chloride)
H-bonding (special dipole-dipole) (2) - electronegativity is high
enough (ex. H2O)
Dispersion (van der Waals) (4) - weak attractions between
molecules that are close to each other (ex. Hydrogen bonding)
◉ 4 Properties of Water.
Answer: adhesion/cohesion, specific temp, density, solvent
(dissolves polar molecules)
◉ Water Soluble.
Answer: Dissolve in water
◉ Explain hydrophobicity based on polarity.
Answer: Polar molecules have charged ends so they mix with water
(hydrophilic) while non polar molecules don't have charged ends do
they don't mix with water (hydrophobicity)
◉ Explain why hydrophobic molecules cluster together in water.
, Answer: Hydrophobic molecules don't mix with water, since they
don't interact with water, they will be attracted to each other,
creating a bond within each other.
◉ Explain how energy is stored in a chemical bond.
Answer: Chemical energy is stored in the bonds of molecules, when
the bond is broken chemical energy is released or absorbed.
◉ Identify the common functional groups.
Answer: Proteins, lipids, carbohydrates, nucleic acids
◉ Dehydration synthesis.
Answer: build molecules up/build energy
◉ Hydrolysis.
Answer: break molecules down/release energy
◉ Hydrophobicity.
Answer: ability of a substance to repel water
◉ Hydrophilic.
Answer: ability of a substance to mix with water
