PHYS 261 WCU Week 1 Practice Test 2026 | Questions &
Answers PDF
1. If the pH of a solution in a biological system drops significantly, what potential
impact could this have on metabolic processes?
It would have no effect on metabolic processes.
It would increase the temperature of the solution.
It could inhibit enzyme activity.
It would enhance enzyme activity.
2. Describe how the structure of phospholipids contributes to their function in
cell membranes.
The hydrophobic head attracts water, making phospholipids dissolve
in the membrane.
The hydrophobic tail interacts with water, preventing the formation of
cell membranes.
The hydrophilic body allows phospholipids to float freely in the
cytoplasm.
The hydrophilic head interacts with water while the hydrophobic
body repels it, allowing phospholipids to form a bilayer that serves
as a barrier.
3. What are polysaccharides composed of?
Composed of large numbers of monosaccharide units connected by
glycosidic linkages
A combination of amino acids
A mixture of sugars and lipids
, A single type of monosaccharide.
4. Describe the structure of an atom and its key components.
An atom consists of orbitals only, with no nucleus present.
An atom consists of a nucleus, which contains protons and neutrons,
surrounded by orbitals where electrons are located.
An atom is a simple particle with no internal structure.
An atom is made up of only protons and electrons without a nucleus.
5. If a patient has an imbalance of potassium ions, what physiological function
might be directly affected?
Cellular respiration
Nerve transmission
Protein synthesis
DNA replication
6. What are the two primary parts of an atom?
A nucleus and orbitals
Protons and electrons
Neutrons and ions
Molecules and compounds
7. DNA is found in the nucleus of cells. What is its main function?
Help maintain protein structure
Make ATP
, Store genetic information
Make proteins
8. An ionic bond is formed by the:
transfer of one or more electrons from one atom to another.
transfer of two or more electrons from one atom to another.
sharing of two or more electrons between atoms.
sharing of one or more electrons between atoms.
9. What is the maximum value on the pH scale?
0
10
14
7
10. Describe the primary function of proteins among the four main types of
macromolecules.
Proteins are primarily involved in energy storage.
Proteins are responsible for genetic information.
Proteins serve as catalysts and provide structural support.
Proteins form the structural framework of cell membranes.
11. What type of molecules are described as having no charge and being
hydrophobic?
Hydrophilic molecules
, Polar molecules
Ionic compounds
Nonpolar molecules
12. Which of the following would be one of the body's controlled variables?
Blood pH
HR, blood pressure
All answers are correct
Body temperature
13. Describe the different types of protein activators and their significance in
biochemical reactions.
Protein activators include proteolytic activators, allosteric
activators, and cofactors, which all enhance the activity of proteins
in biochemical processes.
Protein activators are molecules that degrade proteins and include
proteases.
Protein activators are only found in prokaryotic cells.
Protein activators are substances that inhibit enzyme activity and
include competitive inhibitors.
14. Describe the significance of the octet rule in relation to chemical bonding.
The octet rule is significant because it explains how atoms bond to
achieve a full outermost orbital, leading to stable molecules.
The octet rule is irrelevant to chemical bonding.
The octet rule indicates that atoms can have any number of electrons
in their outermost orbital.
Answers PDF
1. If the pH of a solution in a biological system drops significantly, what potential
impact could this have on metabolic processes?
It would have no effect on metabolic processes.
It would increase the temperature of the solution.
It could inhibit enzyme activity.
It would enhance enzyme activity.
2. Describe how the structure of phospholipids contributes to their function in
cell membranes.
The hydrophobic head attracts water, making phospholipids dissolve
in the membrane.
The hydrophobic tail interacts with water, preventing the formation of
cell membranes.
The hydrophilic body allows phospholipids to float freely in the
cytoplasm.
The hydrophilic head interacts with water while the hydrophobic
body repels it, allowing phospholipids to form a bilayer that serves
as a barrier.
3. What are polysaccharides composed of?
Composed of large numbers of monosaccharide units connected by
glycosidic linkages
A combination of amino acids
A mixture of sugars and lipids
, A single type of monosaccharide.
4. Describe the structure of an atom and its key components.
An atom consists of orbitals only, with no nucleus present.
An atom consists of a nucleus, which contains protons and neutrons,
surrounded by orbitals where electrons are located.
An atom is a simple particle with no internal structure.
An atom is made up of only protons and electrons without a nucleus.
5. If a patient has an imbalance of potassium ions, what physiological function
might be directly affected?
Cellular respiration
Nerve transmission
Protein synthesis
DNA replication
6. What are the two primary parts of an atom?
A nucleus and orbitals
Protons and electrons
Neutrons and ions
Molecules and compounds
7. DNA is found in the nucleus of cells. What is its main function?
Help maintain protein structure
Make ATP
, Store genetic information
Make proteins
8. An ionic bond is formed by the:
transfer of one or more electrons from one atom to another.
transfer of two or more electrons from one atom to another.
sharing of two or more electrons between atoms.
sharing of one or more electrons between atoms.
9. What is the maximum value on the pH scale?
0
10
14
7
10. Describe the primary function of proteins among the four main types of
macromolecules.
Proteins are primarily involved in energy storage.
Proteins are responsible for genetic information.
Proteins serve as catalysts and provide structural support.
Proteins form the structural framework of cell membranes.
11. What type of molecules are described as having no charge and being
hydrophobic?
Hydrophilic molecules
, Polar molecules
Ionic compounds
Nonpolar molecules
12. Which of the following would be one of the body's controlled variables?
Blood pH
HR, blood pressure
All answers are correct
Body temperature
13. Describe the different types of protein activators and their significance in
biochemical reactions.
Protein activators include proteolytic activators, allosteric
activators, and cofactors, which all enhance the activity of proteins
in biochemical processes.
Protein activators are molecules that degrade proteins and include
proteases.
Protein activators are only found in prokaryotic cells.
Protein activators are substances that inhibit enzyme activity and
include competitive inhibitors.
14. Describe the significance of the octet rule in relation to chemical bonding.
The octet rule is significant because it explains how atoms bond to
achieve a full outermost orbital, leading to stable molecules.
The octet rule is irrelevant to chemical bonding.
The octet rule indicates that atoms can have any number of electrons
in their outermost orbital.
