Chapter 2 Flashcards
Molecules of life
An individual molecule is always either hydrophobic or hydrophilic and can never possess at the same time a region that is hydrophobic and a region that is hydrophilic.
A: True
B: false
B: Flase
The basic subunits that make up complex carbohydrate like starch are called
A: monosaccharides
B: glycerol
C: nucleotides
D: amino acids
E: glycosidic bonds
A: monosaccharides
Match the following to their function
- Phospholipid
- Chitin
- Starch
- Cellulose
- Glycogen
A: Plant energy storage
B: Part of cell membrane
C: plant cell wall structural support
D: Animal energy storage
- phosoplipids
- Chitin
- Starch
- Cellulose
- Glucogen
Match the following structures
- The Three- dimensional conformation assumed by a polypeptide chain
- The association of two or more polypeptide to make a functional protein
- The structures held together by hydrogen bond at regular interval along the polypeptide backbone
- The unique sequence of amino acids.
A: Secondary structure
B: Quaternary structure
C: Primary structure
D: Tertiary structure
- D: Tertiary structure
- B: Quaternary structure
- A: Secondary structure
- C: Primary structure
Which of the following are monomers used to make macromolecules that are polymer?
A: Glucose, fatty acids
B: Amino acid, fatty acids
C: amino acids, glycerol
D: amino acids, glucose
D: amino acids, glucose
Which of these… (choose from the options below to answer the following questions)
A: Amino acid A and amino acid B
B: Just amino acid A
C: just amino acid C
D: Amino acid C and amino acid E
E: Amino acid B and amino acid D
- Is/are non-polar hydrophobic amino acids because of the circled functional group
- is/are polar hydrophilic amino acids because of the circled functional group
- is/are charged hydrophilic amino acids because of the circled functional group
- could form an ionic bond between them to stabilize the tertiary structure of protein
- B Just amino acid A
- E Amino acid B and amino acid D
- D Amino acid C and amino acid E
- D Amino acid C and amino acid E
Samples of three different triacylglycerol’s were tested to determine the melting point of each one. the results of the tests are shown in the graph. Which of the three fatty acids is likely to have the least unsaturated fatty acids?
A: Type 1
B: Type 2
C: Type 3
D: There is no way of knowing
B: Type 2
Carbon can form 4 ionic and 4 covalent bonds
A: True
B: False
B: False
What unique property of carbon enables this element to be “life’s chemical backbone”?
A: Carbon is the most abundant element in the universe.
B: Carbon can form double or single bonds.
C: Carbon has four valence electrons.
D: Carbon can form double bonds.
E: Carbon has four electrons
C: Carbon has four valence electrons.
Recall that a carbon atom behaves as if it possesses four valence electrons. Given this information, what is the most likely structural formula for carbon dioxide (CO2)?
A: O=C–O
B: O=C=O
C: O–C–O
D: O–C=O
B: O=C=O
Three carbon atoms are linked by a pair of single covalent bonds in such a way that they form the shape of a V. If the molecule is saturated with hydrogens, how many hydrogen atoms does this molecule contain?
A: 8
B: 6
C: 10
D: 2
E: 4
A: 8
How any hydrogen atoms are present in a five-carbon hydrocarbon molecule with four of the carbons linked in a chain by single covalent bonds and with the fifth carbon atom attached by a single bond as a branch to the second carbon in the chain?
A: 8
B: 10
C: 6
D: 12
D: 12
The basic unit of matter is referred to as a(n):
A: Molecule
B: Ion
C: atom
D: proton
E: neutron
C: atom
Which contributes to the measurement referred to as mass number?
A: protons and neutrons
B: electrons and neutrons
C: protons and electrons
D: protons, electrons, and neutrons
E: neutrons only
A: protons and neutrons
An oxygen (O) atom has _____ protons, _____ neutrons, and _____ unfilled energy shell
A: 8;8;1
B: 8; 16; 2
C: 8; 8; 8
D: 8; 16; 1
E: 16; 8; 1
A: 8;8;1
14C is an isotope of carbon that possesses:
A: 6 protons, 8 neutrons, and 2 electrons.
B: 6 protons, 8 neutrons, and 6 electrons.
C: 8 protons, 6 neutrons, and 2 electrons.
D: 6 protons, 2 neutrons, and 6 electrons
E: 6 protons, 6 neutrons, and 2 electrons.
B: 6 protons, 8 neutrons, and 6 electrons.
For an atom that is not an ion, which statement must be true?
A: The number of neutrons must be less than the number of electrons.
B: The number of protons equals the number of neutrons.
C: The number of electrons equals the number of neutrons.
D: The number of electrons equals the number of protons.
D: The number of electrons equals the number of protons.
You discover an isotope of an element that has 6 electrons in its second and outermost shell (the second shell is the outermost shell), 8 protons, and 6 neutrons. What element is it?
A: fluorine (F)
B: carbon (C)
C: nitrogen (N)
D: oxygen (O)
D: oxygen (O)
Which statement is true regarding elements?
A: Elements are composed of only one type of atom.
B: Elements are only found in inorganic substances and not in living organisms.
C: Elements are still categorized according to Aristotle’s early classifications.
D: Elements are only found in nature and cannot be created by humans.
E: Elements are composed of several different types of atoms.
A: Elements are composed of only one type of atom.
For the first three rows of the periodic table, elements in the same row have the same number and type of:
A: protons
B: energy shell
C: Valence electrons
D: Neutrons
B: energy shell
Use the periodic table to rank the elements carbon, sodium, calcium, and iodine in order of decreasing number of energy shells/levels.
A: Ca, Na, I, C
B: C, I, Ca, Na
C: I, C, Ca, Na
D: I, Ca, Na, C
E: Na, Ca, C, I
D: I, Ca, Na, C
Two elements within the same group:
A: occupy the same row on the periodic table of elements.
B: have different numbers of electrons in their outermost shell.
C: occupy the same column on the periodic table of elements but have different numbers of electrons in their outermost shell.
D: occupy the same column on the periodic table and have the same number of electrons in their outermost shell
E: have the same number of shells.
D: occupy the same column on the periodic table and have the same number of electrons in their outermost shell
pH is:
A: Hydrogen atom concentration in aqueous solution
B: Hydrogen gas concentration in aqueous solution
C: Proton (Hydrogen ion) concentration in aqueous solution
C: Proton (Hydrogen ion) concentration in aqueous solution
Black coffee if more basic than human blood
A: True
B: False
B: False
Solution A is more acidic than solution B. Which of the following is true?
A: Solution A has a higher concentration of hydrogen ions [H+] than solution B.
B: Solution A has a lower concentration of hydrogen ions [H+] than solution B.
A: Solution A has a higher concentration of hydrogen ions [H+] than solution B.
Solution A is more acidic than solution B. Which of the following is true?
A: Solution A has a lower pH than solution B
B: Solution A has a higher pH than solution B.
A: Solution A has a lower pH than solution B
In a periodic table, elements in the same row have the same type of:
A: energy shell
B: Valence electrons
C: protons
D: neutrons
A: energy shell
An ocygen (O) atom has ____ protons, ____ nutrons, and ____ unfilled electron orbitals.
A: 16;8;2
B: 8;8;8
C: 8;16;4
D: 16;8;4
E: 8;8;2
E: 8;8;2
Where is the highest-energy electron found in an atom of hydrogen?
A: in the second spherical orbital, a little farther from the nucleus
B: in the dumbbell-shaped orbital of the y-axis
C: in the spherical orbital closest to the nucleus
D: in the dumbbell-shaped orbital of the z-axis
E: in the dumbbell-shaped orbital of the x-axis
C: in the spherical orbital closest to the nucleus
The designation of a magnesium ion as Mg2+ indicates an atom that has:
A: gained two protons is positively charged.
B: two more protons than neutrons.
C: lost two electrons and is negatively charged
D: lost two electrons and is positively charged
E: gained two protons and is negatively charged.
D: lost two electrons and is positively charged
Na and K, located in the same column in the periodic table of the elements, have the same number of electron orbitals.
A: True
B: False
B: False
How many electron orbitals does a carbon atom possess?
A: 4
B: 6
C: 2
D: 5
E: 12
D: 5
Select all the statements that are true of a molecule of water. some statements will not be used. (select all that apply)
A: Electrons are more likely to be located near the oxygen atom
B: in a molecule of water, the oxygen atom has a slight negative charge
C: hydrogen is more electronegative than oxygen
D: electrons are shared equally between the oxygen atom and both hydrogen atoms.
A: Electrons are more likely to be located near the oxygen atom
B: in a molecule of water, the oxygen atom has a slight negative charge
An atom of nitrogen(N) has __ infilled electron orbitals and will typically form __ covalent bonds with other atoms.
A: 4;4
B: 3;3
C: 4;3
D: 3;6
E: 2;2
B: 3;3
A womans doctor’s tells her to gargle with salt water. She stirs a tablespoon of salt into a cup of warm water and watches the salt dissolve.
Why does the salt dissolve in water?
A: The partial positive charges on hydrogen atoms in water molecules are attracted to sodium ions.
B: The partial negative charges on chlorine atoms are attracted to positive charges on hydrogen atoms in water molecules.
C: The partial negative charges on oxygen atoms in water molecules are attracted to chlorine ions.
D: The partial positive charges on hydrogen atoms in water molecules are attracted to chlorine ions, and the partial negative charges on oxygen atoms in water molecules are attracted to sodium ions
E: The partial positive charges on hydrogen atoms in water molecules are attracted to sodium ion, and the partial negative charges on oxygen atoms in water molecules are attracted to chlorine ions.
D: The partial positive charges on hydrogen atoms in water molecules are attracted to chlorine ions, and the partial negative charges on oxygen atoms in water molecules are attracted to sodium ions
A molecule of common table salt, or NaCL, is the result, or NACl, is the result of ___ bond forming between a sodium(Na) atom had a chlorine (Cl) atom.
A: either an ionic or polar covalent
B: a covalent
C: a hydrogen
D: an ionic
E: a polar covalent
D: an ionic
The ability of atoms to attract electrons is referred to as:
A: hydrophobicity
B: cohesion
C: van der walls attraction
D: potential energy
E: electronegativity
E: electronegativity
The structural formula for hydrogen gas (H2) is presented as H-H. The dash (-) represents the a(n):
A: reactant
B: chemical reaction
C: product
D: chemical bond
E: electronegative bond
D: chemical bond
The valence electrons of an atom are at the lowest energy level because their increased distance from the nucleus reduced their attraction to the atom’s protons.
A: true
B: false
B: false
The description “two of the outermost atomic orbitals of two atoms, each containing one electron merge into a single orbital containing a full complement of two electrons” refers to which type of bonds?
A: covalent bonds
B: hydrogen bonds
C: ionic bonds
A: covalent bonds
If hydrogen bonds between water molecules, collectively, were not as strong as they are, how would this affect plant height?
A: As plants actively transport water through their water-conduction tissues, weaker hydrogen bonds would have no effect on plant height
B: As hydrogen bonds cause water to stick to the side of plant water-conducting tissue, plants would be able to grow taller.
C: As hydrogen bonds increase the amount of sugar plants can transport through their water-conducting tissues, plants would be able to grow taller
D: As hydrogen bonds impede the movement of water through plant water-conducting tissues, plants would be able to grow taller
E: As hydrogen bonds are responsible for the movement of water through plant water conducting tissues, plants would be shorter
E: As hydrogen bonds are responsible for the movement of water through plant water conducting tissues, plants would be shorter
A researcher has measured the pH of a solution and found that the pH is 10. This solution is __ and has more ___ compared to __.
A: basic; hydroxide ions; protons
B: basic; protons; hydroxide ions
C: neutral; hydroxide ions; protons
D: acidic; protons; hydroxide ions
E: acidic; hydroxide ions; protons
A: basic; hydroxide ions; protons
Which statement about water is correct?
A: ice is less dense than liquid water.
B: ice forms on top and sinks to the bottoms of lakes and rivers
C: water molecules in ice demonstrate a disorganized, non-lattice arrangement.
D: bodies of water freeze from the bottom up.
E: ice is more dense than liquid water.
A: ice is less dense than liquid water.
You have an aqueous solution with a pH of 8.0. you add sodium chloride to a concentration of 1 gram per 100 millimeters.
What happens to the pH?
A: it goes up
B: it stays the same
C: it goes down
D: it depends on the temperature.
B: it stays the same
Which bonds occur between two atoms in each of which number of protons does not equal the number of electrons?
A: covalent bonds
B: ionic bonds
C: hydrogen bonds
B: ionic bonds
The oxygen and hydrogens of a water molecule contain what type of bond?
A: van der Waals interactions
B: ionic
C: polar covalent
D: hydrogen
C: polar covalent
What is the mass number of an element with 8 protons and 8 neutrons?
A: 10
B: 12
C: 13
D: 16
E: 8
D: 16
A 1,4-glucosidic linkage would refer to which one of the answer options?
A: hydrogen bonding between carbon 1 and carbon 4 within a monosaccharide
B: hydrogen bonding among the four bases in double-stranded DNA
C: the covalent bond between amino acid 1 in one protein and amino acid 4 in a second protein
D: the covalent bond between the 1’ carbon of one nucleotide and the 4’ carbon of a second nucleotide
E: the covalent bond between carbon 1 of one monosaccharide and carbon 4 of a second monosaccharide
E: the covalent bond between carbon 1 of one monosaccharide and carbon 4 of a second monosaccharide
Which organic molecules are commonly used for energy storage?
A: carbohydrates, nucleic acids, and lipids
B: proteins and nucleic acids
C: lipids and carbohydrates
D: nucleic acids and lipids
E: proteins, carbohydrates, and lipids
C: lipids and carbohydrates
lipids and water do not mix because lipids are ___ and water is ___
A: non-ionic; ionic
B: nonpolar; polar
C: polar, non-polar
D: hydrophilic, hydrophobic
E: unsaturated; saturated
B: nonpolar; polar
oils are ____ with a high level of ___ fatty acids.
A: phospholipids; saturated
B: fatty acids; unsaturated
C: phospholipids; unsaturated
D: triacylglycerol’s; saturated
E: triacyclglycerols; unsaturated
E: triacyclglycerols; unsaturated
Fatty acids that contain no carbon-carbon double bonds are referred to as:
A: phospholipids
B: triacylglycerols
C: saturated
D: unsaturated
E: fats and oils
C: saturated
The linkage of one amino acid to another amino acid in a protein is referred to as a(n):
A: peptide bond
B: glycosidic bond
C: phosphodiester bond
D: ionic bond
E: R groups
A: peptide bond
which choices can combine to form a triacylglycerol molecule? (Select all that apply)
A: cholesterol
B: saturated fatty acid
C: phosphate
D: unsaturated fatty acid
E: glycerol
B: saturated fatty acid
D: unsaturated fatty acid
E: glycerol
Which component of an amino acid differs from one amino acid to another?
A: the hydrogen atm opposite the R group
B: the side chain
C: the a-carbon atom
D: the amino group
E: the carboxyl group
B: the side chain
An unsaturated fatty acid contains:
A: only single covalent bonds between carbon atoms
B: one or more double bonds between carbon atoms
C: one or more double bonds between hydrogen atoms
D: only carbon and hydrogen.
B: one or more double bonds between carbon atoms
aldoses and ketoses are examples of:
A: nucleic acids
B: proteins
C: lipids
D: carbohydrates
E: fatty acids
D: carbohydrates
which bonds are covalent bonds?
A: peptide bonds
B: glycosidic bonds
C: All of these choices are correct
D: ester
C: All of these choices are correct
Because of hydrogen bonding, water is uniquely suited for its central role in life. Many hydrophilic molecules interact freely with water, but a number of hydrophobic molecules are also important for life.
How does the interaction between water and hydrophobic molecules help to organize biological systems?
A: Because cells are not pure water–in that they have many substances dissolved within them–the hydrophilic/hydrophobic effect has a limited role in biological organization.
B: Because water molecules preferentially associate with each other, they force hydrophobic molecules to associate with each other and not with water molecules.
C: None of the other answer options is correct.
D: The ionic bonds between water molecules cause hydrophobic molecules to associate with each other and not with water molecules.
B: Because water molecules preferentially associate with each other, they force hydrophobic molecules to associate with each other and not with water molecules.
For a folding domain that forms a sort of “fist” with certain amino acid R groups buried within and other R groups facing out, the hydrophobic R groups mainly face “out” and the hydrophilic R groups mainly face “in.”
A: true
B: false
B: false
The unfolding of a protein by heat or chemical treatment is referred to as:
A: disaggregation
B: uncoupling
C: hydrolysis
D: depolymerization
E: denaturation
E: denaturation
The fully folded structure of a functional protein composed of a single polypeptide chain is referred to as:
A: secondary structure
B: tertiary structure
C: primary structure
D: quaternary structure
B: tertiary structure
Which of the statements is true regarding glycine?
A: glycine is a large, polar amino acid
B: glycine increases the flexibility of the peptide backbone.
C: glycine is an asymmetric amino acid
D: glycine is special because it contains a -SH group important in protein folding.
E: glycine is similar to tyrosine in terms of structure and chemical properties
B: glycine increases the flexibility of the peptide backbone.
which of the statements is true regarding a basic amino acid?
A: The R group of a basic amino acid would only be able to form covalent bonds with other molecules
B: the positively charged R group of a basic amino acid could bind DNA
C: The hydrophilic R group of a basic amino acid will be located in the interior of a protein.
D: All of these choices are correct
E: A basic amino acid would be considered both poplar and hydrophobic
B: the positively charged R group of a basic amino acid could bind DNA
All polypeptides have tertiary structure
A: true
B: false
A: true
Most proteins retain metabolic activity when denatured.
A: true
B: false
B: false
The sequence of amino acids in a protein is referred to as its primary structure.
A: true
B: false
A: true
which amino acid is capable of forming a disulfide linkage when positioned near another amino acid of the same type?
A: methionine
B: isoleucine
C: arginine
D: tyrosine
E: cysteine
E: cysteine
secondary structure is characterized by which type of interactions?
A: hydrogen bonding within the peptide backbone
B: ionic bonding between an acidic R group and a basic R group
C: hydrogen bonding between R groups of amino acids
D: A covalent bond between two cysteines
E: the covalent bond between amino nitrogen and a carboxyl carbon
A: hydrogen bonding within the peptide backbone
two major types oof protein secondary strictures are referred to as:
A: amino and carboxyl
B: elementary and primary
C: helix and sheet
D: residual and permanent
C: helix and sheet
The function of a protein is dependent upon the shape into which the chain of amino acids folds. Many noncovalent interactions are responsible for maintaining the protein’s shape. Assume you have isolated a protein from an organism in its proper shape, and you have treated it with an enzyme that selectively targets and breaks only the peptide bonds in the proteins. Would the protein retain its shape under these conditions?
A: Yes; once noncovalent bonding determines the shape of a protein, the peptide bonds are no longer necessary.
B: Yes; because the noncovalent interactions that determine the shape of a protein are stronger than the peptide bonds.
C: No; while the noncovalent bonds determine the shape of a protein, the peptide bonds are required to hold the amino acids together.
D: Yes; but the shape would be affected to a greater extent by changes in temperature.
C: No; while the noncovalent bonds determine the shape of a protein, the peptide bonds are required to hold the amino acids together.
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and, in many cases, quaternary structure of the protein, all of which are listed in the answer options. The sentence is taken from a scientific article on protein structure. Select the level of protein structure from the list of options.
There are extensive ionic interactions between positively charged R groups and negatively charged R groups on the polypeptide.
A: primary
B: secondary
C: tertiary
D: quaternary
C: tertiary
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and, in many cases, quaternary structure of the protein, all of which are listed in the answer options. The sentence is taken from a scientific article on protein structure. Select the level of protein structure from the list of options.
Hydrogen bonds between peptide ‘backbone’ components on one polypeptide and R groups on another polypeptide contribute to the overall function.
A: primary
B: secondary
C: tertiary
D: quaternary
D: quaternary
How many water molecules would be produced in making a polypeptide that is 20 amino acids long?
A: 40
B: 18
C: 21
D: 19
D: 19
which force can contribute to a protein’s tertiary structure?
A: Hydrophobic interactions
B: covalent bonding
C: hydrogen bonding
D: all of these choices are correct
E: ionic bonding
D: all of these choices are correct
Disulfide bonds formed between cysteines stabilize the overall structure of this protein isolated for the bacterium.
(select all that apply)
A: primary
B: secondary
C: tertiary
D: quaternary
C: tertiary
D: quaternary
