AP Biology : Understanding Essential Properties of Water
Study concepts, example questions & explanations for AP Biology
All AP Biology Resources
Example Questions
Example Question #21 : Ap Biology
What is the best description of a base?
A compound that releases
A compound or solution that releases 
A nonpolar molecule with covalent bonds
A compound that mixes well with oil
A compound or solution that releases
A compound or solution that is a base releases 
Example Question #21 : Ap Biology
Which of the following is not considered a major component (element) of life?
Nitrogen
Carbon
Iron
Sulfur
Oxygen
Iron
Iron 
Example Question #21 : Ap Biology
Which of the following correctly describes a water molecule?
Nonpolar
Protein
Polar
Organic
Hydrocarbon
Polar
Water is a polar molecule because the bonds between oxygen and hydrogen are polar covalent bonds. This means that although they form covalent bonds (normally non-polar) the difference in electronegativity is great enough to make one side more negative (oxygen side) and the other side more positive (hydrogen side). However, the polarity isn't as strong as the polarity in ionic bonds so we donate the charges with the greek letter delta to show that they are partial charges.
Example Question #22 : Ap Biology
Which of the following reaction is the most common type of catabolic reaction in the human body?
Dehydration
Hydrolysis
Elimination
Addition
Condensation
Hydrolysis
Catabolism means to break something down, usually from a larger starting point to one or more smaller byproducts. Hydrolysis is the most common reaction in the human body. Hydrolysis means "breaking" through the addition of a water molecule. You will see hydrolysis as an important reaction in many pathways in the human body.
Example Question #23 : Ap Biology
An alcohol group is indicated by which side chain when looking at the structure of a molecule?
An alcohol group is written as 
Example Question #22 : Ap Biology
When the concentration of solutes differs on the two sides of a membrane permeable only to water, what will occur?
Water will move across the membrane by active transport.
Water will move across the membrane by plasmolysis.
Water will move across the membrane by facilitated diffusion.
Water will move across the membrane by osmosis.
The solutes will move across the membrane from a region of higher concentration to the region of lower concentration.
Water will move across the membrane by osmosis.
When there is a concentration gradient, water will move across a membrane unassisted by ATP or channel proteins. In contrast, solutes (the dissolved substances) cannot cross the membrane unassisted.
Certified Tutor
All AP Biology Resources
