A substance that stabilizes pH by releasing or binding hydrogen ions is a(n) _______________.
buffer
electrolyte
acid
base
When a protein’s hydrogen bonds are broken due to high temperature or pH changes, the process is called ___________________.
denaturation
synthesis
polymerization
deamination
Enzymes are a part of which macromolecule group?
proteins
Enzymes function by __________________________.
increasing the amount of activation energy
becoming permanently altered in the chemical reaction
lowering the amount of activation energy
slowing down chemical reactions
Covalent bonds are formed by ________________.
the transfer of electrons
the sharing of electron pairs
hydrogen bonding between polar molecules
the attraction between oppositely charged ions
Which of the following best describes an endergonic reaction?
requires enzymes to occur
releases energy
absorbs energy
occurs only in the absence of oxygen
Which of the following best describes an exergonic reaction?
releases energy
occurs only in the absence of oxygen
absorbs energy
requires enzymes to occur
The most abundant inorganic compound in the human body is _________________.
oxygen
sodium chloride
carbon dioxide
water
The primary function of carbohydrates in the human body is ________________________.
insulation and protection
energy source
structural support
enzyme production
What are molecular chaperones, and what is their function in the cell?
Molecular chaperones are special proteins that assist other proteins in folding into their correct 3D shapes. They help prevent misfolding
Which of the following is an example of a medical use of radioactive isotopes?
biological tracers
radiation therapy for cancer
diagnostic imaging
all of these
Explain what would happen to a protein’s function if it would be subjected to high fever or extreme pH.
protein could become denatured due to high temp
In DNA, the complementary base to Adenine would be __________________.
Glycine
Cytosine
Thymine
Guanine
Describe the significance of water being the universal solvent in the human body.
Water’s polarity allows it to dissolve many substances, including salts, sugars, enables nutrient transport, waste removal, chemical rxns occur
The polarity of water contributes to all of the following EXCEPT ______________.
ability to dissolve salts
formation of nonpolar covalent bonds
cohesion between molecules
high heat capacity
When a protein is denatured, it _______________________.
becomes more reactive
forms peptide bonds
maintains its function
loses shape and function
The smallest unit of an element that still retains the properties of that element is called a(n) ________________.
proton
atom
molecule
compound
The primary role of triglycerides in the human body is to _____________.
store genetic information
catalyze metabolic reactions
form the protective phospholipid bilayer
provide insulation and long-term energy storage
The apoenzyme portion of a holoenzyme _____________________.
denatures under high temperature
is the non-protein cofactor required for activity
provides energy for the reaction
the protein portion of enzyme responsible for specificity
The most abundant and versatile macromolecule in the human body is ___________________________________.
nucleic acids
proteins
carbohydrates
lipids
Which of the following best defines an element?
A substance that cannot be broken down by normal means
A form of energy that has mass
A combination of two or more compounds
A substance that can be broken down into simpler substances
Explain the significance of water’s high heat capacity and high heat of vaporization in maintaining homeostasis.
helps the body resist sudden temperature changes, keeping cells and tissues stable. high heat of vapor. allows the body to cool when sweating
The process of hydrolysis is important in metabolism because it _________________________________.
removes water to form bonds
joins monomers together
converts ATP into ADP and phosphate
breaks down polymers into smaller units
Name the monomer of nucleic acids.
nucleotides
An acid is a compound that ____________________.
Neutralizes bases by releasing hydroxide ions (OH-)
releases hydrogen ions (H+) in solution
increases pH in solution
accepts hydrogen ions (H+) in solution
Which macromolecule type serves as enzymes, hormones, and antibodies?
nucleic acids
proteins
lipids
carbohydrates
Which of the following accurately describes DNA?
Contains the sugar ribose and base uracil
Double-stranded, stores genetic information
Single-stranded and found mainly in the cytoplasm
Forms from the translation process
The atomic number of an element is equal to the number of _________________.
neutrons
all of these
electrons
protons
Which part of an amino acid gives each one its unique chemical properties?
Carboxyl group
Hydrogen atom
Amino group
R (side) group
A solution with a pH of 8 is _____________________.
a weak acid
a strong base
a strong acid
a weak base
Name the basic monomer of lipids.
fatty acids and glycerol
Hemoglobin functions as a _______________________.
structural protein providing tensile strength
enzyme for digestion
hormone regulating blood sugar
transport protein carrying oxygen
Enzyme activity can be affected by all of the following EXCEPT __________________________.
temperature
pH
DNA sequence
concentration of enzyme or substrate
The high heat of vaporization of water is significant because it _________________.
prevents hydrogen bonding
causes ice to sink
decreases metabolic rates
allows the body to cool through sweating
Which subatomic particle carries a negative charge?
neutron
proton
electron
During hydrolysis reactions, _______________________________________________.
bonds are formed between monomers
water is added to break bonds
energy is absorbed
water is removed to form bonds
The structure of ATP is most similar to ________________.
a monosaccharide
a nucleotide
a triglyceride
an amino acid
A decomposition reaction is represented as:
AB --> A + B
AB + CD --> AD + BC
A + B --> AB
AB + C --> A + BC
Describe why energy conversions are considered to be “inefficient”?
Energy conversions are inefficient because some energy is always lost as heat or other unusable forms during the process.
The most important role of nucleic acids is to ____________________________.
catalyze metabolic reactions
form biological membranes
store and transmit genetic information
provide quick energy
Which type of lipid is most important in cell membrane structure?
wax
phospholipid
triglyceride
steroid
Why is it important that some radioisotopes used in diagnostic imaging have short half-lives?
Short half-lives are important because the radioisotopes decay quickly, minimizing radiation exposure to the patient while still providing enough time to produc
The most common element combinations that form organic molecules include ___________________.
Na, Cl, K, Ca
Fe, Cu, Zn, Mg
C, H, O, N, P, S
P, S, I, Se
Glycogen is primarily stored in which two organs?
liver and skeletal muscle
heart and lungs
stomach and pancreas
brain and kidneys
Which macromolecule serves as the primary short-term energy source for most cells?
nucleic acids
proteins
carbohydrates
lipids
Isotopes of an element have different numbers of _________________.
protons
neutrons
all of these
electrons
The process of breaking down glycogen into glucose monomers is an example of _________________.
reduction
hydrolysis
oxidation
dehydration synthesis
An ionic bond is formed when ___________________.
electrons are transferred from one atom to another
two atoms share protons
to ions repel each other
electrons are shared between two atoms
Explain why fluid and electrolyte balance is critical for human health.
Fluid and electrolyte balance is essential for maintaining normal hydration, nerve impulses, muscle contraction, blood pressure, and overall cellular function.
Why are buffers critical in the human body?
Buffers are critical because they maintain a stable pH in body fluids, which is essential for enzyme function, chemical reactions, and overall cellular health.
Which type of reaction results in the formation of larger molecules from smaller building blocks?
Exchange reaction
Decomposition reaction
Oxidation reaction
Synthesis reaction
Proteins are the most functionally diverse macromolecule group because _______________.
they are composed only of hydrogen and oxygen
they are nonpolar and stable
the sequence of 20 amino acids can form countless combos
their structure is determined only by temperature
Which of the following is NOT a function of proteins in the human body?
Energy storage
Hormone regulation
Transport and movement
Enzymatic catalysis
Which statement about hydrogen bonds is FALSE?
They are responsible for the shape of DNA molecules.
They help water remain liquid at room temperature.
They form between partially charged atoms.
They are strong covalent bonds.
In a chemical equation, the substances on the left side of the arrow are the:
products
reactants
catalysts
enzymes
Name the monomer of carbohydrates
monosaccharides
The sequence of amino acids in a protein represents its _______________________.
secondary structure
quaternary structure
primary structure
tertiary structure
Which lipid molecule acts as a chemical messenger in the body?
Steroid
Triglyceride
Phospholipid
Cholesterol
Name the monomer of proteins
amino acids
Describe what would happen to a chemical reaction in the body if the enzyme required for it was missing.
The reaction would occur much more slowly or may not occur at all under normal physiological conditions.
Explain why water’s cohesion is important for processes like capillary action in plants or blood flow in humans.
Cohesion allows water molecules to stick together, helping it move through narrow vessels and tubes efficiently.
What form of energy is used to transmit messages from one part of the body to another?
chemical energy
potential energy
mechanical energy
radiant energy
The main energy currency of cells is _________.
ATP
The process that joins monomers to form polymers by removing water is called __________________.
hydrolysis
dehydration synthesis
all of these
neutralization
The phospholipid bilayer of the plasma membrane is essential because ___________________________.
it allows all substances to pass freely
it is composed entirely of carbohydrates
it forms a selective barrier due to hydrophobic/hydrophilic
it provides rigid support
The term polar molecule refers to ________________________________________.
A molecule that lacks hydrogen atoms
A molecule with an uneven distribution of charge
A molecule with equal charge distribution
A molecule held together by nonpolar covalent bonds
The energy stored in ATP is located in its _______________________.
ribose sugar
adenine base
nitrogen atoms
high-energy phosphate bonds
The process of joining two monosaccharides to form a disaccharide involves a(n) _______________________.
dehydration synthesis reaction
hydrolysis reaction
oxidation reaction
reduction reaction
Which statement about lipids is TRUE?
They are insoluble in water but soluble in other lipids.
They are all polar molecules.
They are composed of repeating amino acid units.
They are the body’s main immediate energy source.
Explain the difference between kinetic and potential energy and give an example of each in the human body.
PE is stored energy, such as the energy in ATP or chemical bonds in glucose. KE is energy in motion, such as muscle contraction or nerve impulses that use ATP
The formation of peptide bonds between amino acids occurs through ___________________.
neutralization
hydrolysis
dehydration synthesis
oxidation
The process that breaks down polymers into monomers by adding water is called ____________.
neutralization
all of these
hydrolysis
dehydration synthesis
Which of the following is an example of an inorganic cofactor that is part of a holoenzyme?
ATP
NAD+
Zinc ion (Zn2+)
DNA
What form of energy is found in the foods we eat?
chemical energy
all of these
electrical energy
mechanical energy
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