Unit 1 AP Biology
Dehydration synthesis leads to the formation of what?
polymers
Cellulose and starch are examples of ________.
polysaccharides
What is found in RNA that is not in DNA?
ribose and uracil
Which of the following is least likely to bond with carbon as a functional group in biological systems?
sodium
Which of the following is a function of proteins in cells?
structure
What is the smallest type of RNA?
tRNA
Define water's property of adhesion.
the attraction between water molecules and other molecules
Which structural level of proteins is most often associated with their biological function?
the primary structure
The αα-helix and the ββ-pleated sheet are part of which protein structure?
the secondary structure
Figure 1. Polypeptide reaction Which statement is the most accurate description of the reaction shown in Figure 1?
It represents a polypeptide chain that is broken down through a hydrolysis reaction.
What may a nucleotide of DNA contain?
deoxyribose, thymine, and a phosphate group
Energy is released as a result of which of the following chemical reactions?
dissolution
What is the maximum number of atoms or molecules a single carbon atom can bond with?
4
If xenon has an atomic number of 5454 and a mass number of 108108, how many neutrons does it have?
54
Which of the following statements is true?
Acids and bases can neutralize each other.
Which of the following conclusions is most clearly supported by the representations of nucleic acid #1 and nucleic acid #2 ?
Nucleic acid #1#1 contains adenine-thymine base pairs, whereas nucleic acid #2 does not
Explain why the bonds within a water molecule are described as polar covalent bonds.
Oxygen is more electronegative than hydrogen, generating a partial negative charge near the oxygen atoms.
What type of amino acids would you expect to find on the surface of proteins that must interact closely with water?
Polar Amino Acids
. Potassium has an atomic number of 19. What is its electron configuration?
Shells 1, 2, and 3 are full, and shell 4 has one electron.
Which of the following best describes the structures of carbohydrates?
They occur as monomers, chains of monomers, and branched structures.
Which of the following characteristics is not true for saturated fats?
They tend to dissolve in water easily.
Which of the following statements is not true?
Water is the most abundant molecule in the Earth's atmosphere.
What is DNA's structure described as?
a double helix
What molecule is joined with glucose to form the disaccharide lactose, and what type of bond joins these molecules?
a glycosidic bond between glucose and galactose
What is cholesterol specifically classified as?
a steroid
How are excess hydrogen ions balanced in a solution?
acid
Which of the following may cause a protein to denature?
all of the above: changes in pH, high temperatures, and the addition of some chemicals
What are the monomers that make up proteins called?
amino acids
What type of protein facilitates or accelerates chemical reactions?
an enzyme
Which of the following functional groups is the least polar?
methyl
What are enantiomers?
molecules sharing the same chemical bonds but are mirror images of each other
Where is the linkage made that combines two amino acids?
between the carboxyl group of one amino acid and the amino group of the other
Plant cell walls contain which of the following in abundance?
cellulose
What are the building blocks of nucleic acids?
nucleotides
Figure 1. Formation of a peptide bond Which of the following best describes the formation of the bond shown in Figure 1 ?
A covalent bond is formed between a carbon atom and a nitrogen atom along with the formation of H2OH2O .
Based on Figure 1, which of the following best describes how the properties of water at an air-water interface enable an insect to walk on the water's surface?
Hydrogen bonds between molecules at the surface of the water provide surface tension, which allows the water surface to deform but not break under the insect.
In the metabolism of a cell, why is hydrolysis used?
Hydrolysis synthesizes new macromolecules.
Which of the following statements is false?
In solution, ionic bonds are generally stronger than covalent bonds.
Which of the following best describes a structural difference between DNA and RNA?
The backbone of DNA contains deoxyribose, whereas the backbone of RNARNA contains ribose.
Figure 1. Structural formula for a common biological reaction Which of the following is an accurate description of the process shown in Figure 1 ?
The formation of a covalent peptide bond in a dehydration synthesis reaction
Which of the following characteristics of Figure 1 best shows that the fragment is RNA and not DNA?
The identity of each nitrogenous base
Which of the following best describes how amino acids affect the tertiary structure of a protein?
The interactions of the different RR-groups with other RR-groups and with their environment determine the tertiary structure of the protein.
Which statement best helps explain the formation of the hydrogen bond represented in the figure?
The nitrogen has a partial negative charge, and the hydrogen attached to the oxygen has a partial positive charge.
What happens to the pH of a solution when acids are added?
The pH of the solution decreases.
Where is cholesterol found in cell membranes?
floating in the phospholipid tail layer
What is an example of a monosaccharide?
fructose
Which type of bond exemplifies a weak chemical bond?
hydrogen bonds in solution
During the breakdown of polymers, which of the following reactions takes place?
hydrolysis
What is removed during the formation of nucleic acid polymers?
hydroxyl groups
Where is the largest amount of DNA found in a eukaryotic cell?
in the nucleus
What forms ionic bonds?
ions with opposite charges
What is the term for atoms of the same element that vary in the number of neutrons in their nuclei?
isotopes
What makes up the outer layer of some insects?
triglyceride
Which fat serves as an animal's major form of energy storage?
triglycerides
Which fat has the least number of hydrogen atoms?
unsaturated fat