WorksheetsUnit 1: Chemistry of Life
Total questions: 82
Worksheet time: 44mins
Which of the following does not result from hydrogen bonding in water molecules?
Cohesion
Adhesion
Surface Tension
Dissolving fats
Why is water considered polar?
Nonpolar covalent bonds in structure
Ionic bonds in structure
Polar covalent bonds in structure
Hydrophobic interaction in structure
Which macromolecule(s) have nitrogen?
Carbohydrates
Proteins
Nucleic Acids
Nucleic Acids & Proteins
Which macromolecule(s) have phosphorus?
Carbohydrates
Proteins
Nucleic Acids
Fats
Which macromolecule(s) have sulfur?
Carbohydrates
Proteins
Nucleic Acids
Fats
Describes the forming of a bond between monomers with the removal of a water molecule.
Hydrolysis
Dehydration
Describes the breaking of a bond within a polymer using water.
Hydrolysis
Dehydration
Which of the following is NOT in the monomer of a nucleic acid?
pentose sugar
nitrogenous base
phosphate
amino acid
Which of the following is NOT in the monomer of a protein?
Amine Group
R Group
Carboxyl Group
Nitrogenous Base
Describe the orientation of the phospholipids in the membrane.
Phospholipids orient in bilayer with hydrophilic heads on exterior
Phospholipids orient in monolayer with hydrophilic head on extracellular
Phospholipids orient in bilayer with hydrophobic tails on exterior
Phospholipids orient in monolayer with hydrophobic tails on extracellular
How is DNA/RNA synthesis directionally oriented?
new nucleotides are added to 5' phosphate
new nucleotides are added to 3' phosphate
new nucleotides are added to 5' hydroxyl
new nucleotides are added to 3' hydroxyl
Identify the pairing and number of bonds in DNA double helix
A pairs with T (2 bonds) & G pairs with C (3 bonds)
A pairs with G (2 bonds) & T pairs with C (3 bonds)
A pairs with T (3 bonds) & G pairs with C (2 bonds)
A pairs with G (3 bonds) & T pairs with C (2 bonds)
How is DNA/RNA synthesis directionally oriented?
new nucleotides are added to 5' phosphate
new nucleotides are added to 3' phosphate
new nucleotides are added to 5' hydroxyl
new nucleotides are added to 3' hydroxyl
What component of the polypeptide is the next amino acid added forming the peptide bond?
amino group
hydrogen
carboxyl group
R groups
Which protein involves R group bonding to form the final three dimensional structure?
primary
secondary
tertiary
quaternary
Which protein structure involves the peptide bonds between amino acids?
primary
secondary
tertiary
quaternary
DNA and RNA differ on many qualities, which of the following is NOT a difference?
Sugar
Nitrogenous Base
Phosphate Group
Strandedness
A covalent chemical bond is one in which
electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged.
protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms.
outer-shell electrons of two atoms are shared so as to satisfactorily fill the outer electron shells of both atoms.
What gives rise to the cohesiveness of water molecules?
hydrophobic interactions
nonpolar covalent bonds
ionic bonds
hydrogen bonds
Which of the following statements is/are true regarding the chemical reaction illustrated in the Figure?
It is a hydrolysis reaction.
It results in a peptide bond.
It joins two fatty acids together.
Which of the following best describes water's ability to dissolve certain substances such as glucose, but remain separate from other substances such as oils?
Water molecules are polar, consisting of two partially positive hydrogen atoms, and one partially negative oxygen atom.
Water molecules can only form ionic bonds with polar molecules, such as glucose.
Due to hydrogen bonding, water is more dense as a liquid than a solid.
Water has an overall negative charge, which allows it to easily dissolve nonpolar substances like glucose.
Which of the following examples explains how biological activity relies on water's adhesive properties?
Water travels through vascular tissue (xylem) from the roots to the leaves of a plant.
Stomata (openings) in leaves control transpiration of water out of the leaf as water vapor.
Vacuoles in plant cells swell as water dilutes the contents of the vacuole.
Feathers retain an oily coating that repels water droplets.
Given the structure of water (H2O), which of the following must be true?
Each water molecule can form four hydrogen bonds.
Each water molecule will form covalent bonds with its neighbors.
Water has an overall negative charge.
Water is able to easily dissolve nonpolar substances.
Which of the following describes a covalent bond?
It involves an atom that gains an electron.
Two or more atoms share electron pairs.
Molecules linked by covalent bonds are less dense when in solid form than when in liquid form.
A hydrogen atom with a partial positive charge is attracted to another atom with a partial negative charge.
Which of the following statements regarding carbon is FALSE?
Carbon has the capacity to form single and double bonds.
Carbon has the ability to bond together to form extensive branched or unbranched "carbon skeletons."
Carbon has the ability to bond with up to six other atoms.
Carbon has a tendency to form covalent bonds.
Which of the following best describes the role that water plays in the reaction depicted here?
Water catalyzes the formation of a covalent bond in the dimer through hydrolysis.
When water condenses out of the reaction, a dimer is created as a covalent bond forms between two monomers.
When water combines with the two monomers, a dimer forms.
Water is an input of the reaction, leading to the formation of a covalent bond in the dimer product.
Which of the following questions would a researcher most likely ask if they wanted to know whether a hydrolysis reaction or a dehydration synthesis reaction is occurring?
Are the monomers identical to one another?
Is an enzyme involved in the reaction?
Which polymer is involved in the reaction?
Is water a reactant or product of the reaction?
Lactose is a dimer sugar composed of two monomeric subunits (galactose and glucose). In an investigation, researchers placed intestinal cells in a nutrient medium containing lactose. The researchers determined that the lactose had broken down to galactose and glucose in the manner depicted in the reaction shown here.
The cells were then modified and re-exposed to the lactose medium. The researchers were no longer able to detect the presence of galactose and glucose. Which of the following conclusions best explains an outcome of this modification?
The cells were unable to hydrolyze lactose, resulting in the formation of a covalent bond between galactose and glucose.
The cells were unable to hydrolyze the lactose dimer into its monomeric subunits.
The cells were able to perform dehydration synthesis reactions in order to break down lactose into its monomeric subunits.
The cells were able to undergo a reverse reaction and build lactose.
A researcher wants to identify a newly isolated DNA strand. The first step in identifying the DNA strand is to measure its length. To do this, the researcher wants to develop a fluorescent tag that emits light once it binds to both ends of the strand.
Which of the following best describes how the researcher should develop a fluorescent tag with an ability to bind to both ends of the strand?
The tag should have an affinity to bind only guanine (G) and cytosine (C) nitrogenous bases.
The tag should have an affinity to bind only free amino (-NH2) and carboxyl (-COOH) functional groups.
The tag should have an affinity to bind only adenine (A) and thymine (T) nitrogenous bases.
The tag should have an affinity to bind only free 3' hydroxyl (-OH) and 5' phosphate (-PO4) functional groups.
The image depicts how the bacterial protein barnase undergoes modifications that involve changing its conformation, or shape. In order to function in the cell, barnase has to be folded from a nonfunctional conformation into a functional conformation.
The functional conformation of barnase has a tertiary structure because it consists of a polypeptide chain folded into a three-dimensional shape.
The functional composition of barnase has a quaternary structure because it consists of interactions between multiple polypeptide units.
The functional composition of barnase has a secondary structure because it consists of a single alpha-helix.
The functional composition of barnase has a primary structure because it consists of a linear chain of amino acids.
Amino acids can be distinguished from one another by
the number of R groups found on the amino acid molecules.
the type of bond between the R group and the rest of the amino acid molecule.
the chemical properties of their R groups.
the chemical properties of their amino and carboxyl groups.
Which of the following statements about enzymes is false?
They are monomers used to build proteins.
They regulate virtually all chemical reactions in a cell.
They function as chemical catalysts.
They increase the rate of chemical reactions.
Your first big biology exam is coming up in a few days, and in order to prepare for late-night study sessions, you buy a box of Yummies, a delicious type of snack cake. After checking out the nutrition facts label on the side of the box, you discover that a single Yummie cake contains 4.5 grams of total fat, 27 grams of carbohydrate, 0 grams of fiber, and 1 gram of protein.
The pH of the stomach is extremely acidic (~ pH 2). If you ate a Yummie cake, what do you think would happen to the protein that you ingested as it passes through the stomach?
The protein would form longer proteins via dehydration reactions.
The protein would get broken down via dehydration reactions.
The protein would become denatured due to the acidic environment.
The protein would speed up digestion because it is an enzyme.
What is the complementary sequence to the DNA strand TCGATGG?
AGCUACC
AGCTACC
GGTAGCT
TCGATGG
Which of the following correctly matches the macromolecule with its monomer?
carbohydrates: monosaccharides
proteins: polysaccharides
lipids: nucleotides
nucleic acids: polypeptides
In the cell membrane, carbohydrate chains can be covalently linked to membrane proteins to form glycoproteins. They can also be covalently linked to membrane phospholipids to form glycolipids. These two cell membrane structures are shown in the image provided.
During an investigation, researchers discover a new toxin that enters a cell after binding to a carbohydrate on the cell membrane. Which of the following best describes how the toxin attaches to the cell membrane?
The toxin attaches to specific phospholipids on the cell membrane.
The toxin attaches to specific amino acids on the cell membrane.
The toxin attaches to specific fatty acids on the cell membrane.
The toxin attaches to specific monosaccharides on the cell membrane.
Cowpox is classified as a DNA virus because its genome, or genetic material, consists of double-stranded DNA.
Which of the following claims is best supported by the information above?
Cowpox contains a five-carbon sugar called ribose in its nucleic acid structure.
Uracil nucleotides are not found in the cowpox genome.
Cowpox has a single-stranded nucleic acid structure.
Thymine nucleotides are not found in the cowpox genome.
The following excerpt describes a potential origin of the first living cells on earth:
"We have proposed that a simple primitive cell, or protocell, would consist of two key components: a protocell membrane that defines a spatially localized compartment, and an informational polymer that allows for the replication and inheritance of functional information."
Based on this excerpt, which of the following questions would best direct an investigation on whether the "informational polymer" is DNA or RNA?
Which type of bonds connect individual nucleotides in the sugar-phosphate backbone of the informational polymer?
Which nitrogenous bases are present in the structure of the informational polymer?
Which functional group is located on the 3' end of the informational polymer?
Which functional group is located on the 5' end of the informational polymer?
Which of the following molecules is a carbohydrate?
C51H98O6
C22H49O10N5
C45H84O8P4
C60H100O50
