AP Biology First Semester Final Exam Review Questions and
Answers
Question 1
Which four elements make up approximately 96% of living matter?
Correct Answer
carbon, hydrogen, nitrogen, oxygen
Question 2
What do cohesion, surface tension, and adhesion have in common with reference to water?
Correct Answer
all properties related to hydrogen bonding
Question 3
Why does ice float in liquid water
Correct Answer
Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water.
Page 1 of 28
,Question 4
What makes a substance hydrophobic?
Correct Answer
It has a large area that is nonpolar, hence no attraction to water
Question 5
Which property of the carbon atom gives it compatibility with a greater number of different elements than any other type
of atom?
Correct Answer
is able to form 4 single bonds
Question 6
What is the ultimate source of carbon that is found in organic molecules?
Correct Answer
The ultimate source of all organic molecules is primary production, in which photosynthetic organisms take in carbon
dioxide gas (or bicarbonate - CO2's water-dissolved form) and, using sunlight as an energy source, convert it into
glucose.
Question 7
The element nitrogen is present in what types of organic molecules?
Correct Answer
proteins and nucleic acids
Page 2 of 28
, Question 8
What are polysaccharides made of?
Correct Answer
Polysaccharides are long chains of monosaccharides linked by glycosidic bonds.
Question 9
How is the synthesis of polysaccharides, lipids, and proteins similar?
Correct Answer
They are all synthesized from monomers by dehydration reactions.
Question 10
Why can humans digest starch but not cellulose?
Correct Answer
humans have enzymes that can hydrolyze the alpha glycosidic linkages of starch but not the beta glycosidic linkages of
cellulose
Question 11
Why do the 20 different amino acids found in polypeptides exhibit different chemical and physical properties?
Correct Answer
different side chains (R groups)
Page 3 of 28
Answers
Question 1
Which four elements make up approximately 96% of living matter?
Correct Answer
carbon, hydrogen, nitrogen, oxygen
Question 2
What do cohesion, surface tension, and adhesion have in common with reference to water?
Correct Answer
all properties related to hydrogen bonding
Question 3
Why does ice float in liquid water
Correct Answer
Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water.
Page 1 of 28
,Question 4
What makes a substance hydrophobic?
Correct Answer
It has a large area that is nonpolar, hence no attraction to water
Question 5
Which property of the carbon atom gives it compatibility with a greater number of different elements than any other type
of atom?
Correct Answer
is able to form 4 single bonds
Question 6
What is the ultimate source of carbon that is found in organic molecules?
Correct Answer
The ultimate source of all organic molecules is primary production, in which photosynthetic organisms take in carbon
dioxide gas (or bicarbonate - CO2's water-dissolved form) and, using sunlight as an energy source, convert it into
glucose.
Question 7
The element nitrogen is present in what types of organic molecules?
Correct Answer
proteins and nucleic acids
Page 2 of 28
, Question 8
What are polysaccharides made of?
Correct Answer
Polysaccharides are long chains of monosaccharides linked by glycosidic bonds.
Question 9
How is the synthesis of polysaccharides, lipids, and proteins similar?
Correct Answer
They are all synthesized from monomers by dehydration reactions.
Question 10
Why can humans digest starch but not cellulose?
Correct Answer
humans have enzymes that can hydrolyze the alpha glycosidic linkages of starch but not the beta glycosidic linkages of
cellulose
Question 11
Why do the 20 different amino acids found in polypeptides exhibit different chemical and physical properties?
Correct Answer
different side chains (R groups)
Page 3 of 28
