Bio midterm review Bio midterm review 2/18/2026
Combined Practice /71
51 MCQs (51 points)
1. Which of the following is NOT a reason that Carl Woose and other authors of the domain article proposed
to reorganize the 6 kingdom classification system into a new system that has 3 domains as the broadest
categories (CH1)
a. Organisms in the Domain Archea were equally as different from organisms in Domain Eukarya as
they are from Domain Bacteria and therefore should be categorized in their own domain
b. Historically, life was organized based solely on morphological characteristics, however, with
recent advancements in technology, they have indicated that there are 3 distinct phylogenetic
branches in the tree of life
c. It is understood that cells have taken 3 very different paths since the occurrence of a LUCA (Last
Universal Common Ancestor) which existed about 3.8 billion years ago
d. The RNA molecules found in the organisms within the Domain Eukarya, Domain Prokarya, and
Domain Archea were all too similar to be put into 6 different kingdoms
2. Which statement about the properties of life is false (CH1)
a. Organisms can respond to their environment
b. Organisms have the ability to take in energy and use it
c. Organisms have unchanging, constant internal environments
d. Organisms have the ability to reproduce
3. In a water molecule, the hydrogen and oxygen atoms are each held together by a ______________bond. (CH2)
a. Nonpolar covalent
b. Polar Covalent
c. Hydrogen bonds
d. Double covelant
4. In a temperate forest ecosystem, both biotic and abiotic factors shape the dynamics of plant and animal
populations. The following factors are at play in this ecosystem:
● Abiotic factors: Seasonal changes in temperature, annual rainfall, soil pH, and light intensity.
● Biotic factors: Predator-prey interactions (foxes and rabbits), competition for resources (trees competing
for light, herbivores competing for plants), and mutualistic relationships (e.g., nitrogen-fixing bacteria in
the roots of plants).
Which of the following statements best describes how the interaction of biotic and abiotic factors can influence the
dynamics of this temperate forest ecosystem? (CH1)
A) Changes in soil pH can directly influence the rate of nitrogen fixation by bacteria, but they have little impact on
the plant species composition since trees and shrubs are not affected by pH levels.
B) The seasonal variation in temperature is an abiotic factor that can affect both the metabolic rates and reproductive
success of foxes and rabbits, leading to seasonal fluctuations in population size due to increased or decreased
predator-prey interactions.
C) Competition between trees for light can result in competitive exclusion, where one species of tree completely
eliminates another, and this competition is unaffected by seasonal temperature changes.
D) The mutualistic relationship between nitrogen-fixing bacteria and trees enhances soil fertility, which directly
influences the growth of herbivorous plant species, but has no impact on higher trophic levels like foxes and rabbits.
E) Abiotic factors, such as rainfall and temperature, directly influence the availability of food for herbivores like
rabbits but do not impact predator species such as foxes, because foxes are not dependent on seasonal changes for
survival.
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5. Which of the following statements best describes the relationship between the hierarchy of life and the concept of
emergent properties? (CH1)
A) At the organ system level, the complexity of biological functions is reduced because each organ system operates
independently, without interacting with others.
B) The cellular level represents the highest level of organization in the biological hierarchy, where all functions
necessary for life are carried out. Organisms can exist at the cellular level without higher levels of organization.
C) Emergent properties, such as population growth and species interactions, arise at the population level and cannot
be predicted from the characteristics of individual organisms.
D) At the biosphere level, life processes cease to be relevant because the interaction between living organisms and
their environment leads to a lack of complexity, making ecosystems homogeneous.
6. A student used a microscope to observe a wet-mount slide of red onion epidermal cells that were suspended in a
1% NaCl solution. The student then added a 15% NaCL solution to the slide and observed the changes that occurred.
The student’s observations are represented in Figure 1. Which of the following most directly explains the changes in
the cells? (CH5)
(A) The degradation of DNA in the nuclei of the cells
(B) The lysis of chloroplasts in the cells
(C) The movement of water from the central vacuoles of the cells into the solution
(D) The movement of NaCl from the solution into the cytoplasm of the cells
7. The enzyme trypsin aids in protein digestion in the small intestine. The relative activity of trypsin at different pH
values is shown in Figure 1.
Which of the following statements best explains the activity levels of trypsin shown in Figure 1? (CH5)
(A) The small intestine releases inhibitor molecules that block the activity of trypsin unless it is at its optimum pH.
(B) The number of effective collisions between trypsin and its substrate increase at higher pH values.
(C) As pH values increase, the substrate concentration decreases, leading to an eventual decline in the rate of the
trypsin-catalyzed reaction.
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(D) At extremely low pH values, trypsin is denatured and cannot function efficiently
8. Scientists examined the folded structure of a purified protein resuspended in water. They found that amino acids
with nonpolar R groups were primarily buried in the middle of the protein. In contrast, amino acids with polar R
groups were primarily on the surface of the protein. Which of the following best explains the location of the amino
acids in the folded protein? (CH3)
(A) Polar R groups on the surface of the protein can form ionic bonds with the charged ends of the water molecules.
(B) Polar R groups are too bulky to fit in the middle of the protein and are pushed toward the protein’s surface.
(C) Nonpolar R groups that cannot form hydrogen bonds with water are pushed into the middle of the protein.
(D) Nonpolar R groups from different parts of the protein form covalent bonds with each other to maintain the
protein’s structure.
9. Which of the following best describes the R chain of this amino acid (Serine)? (CH3)
(A) Polar Uncharged
(B) Non-Polar Noncharged
(C) Polar positive charge
(D) Polar negative charge
10. The model below shows how glucose and sodium ions move between the intestinal lumen, an epithelial cell,
and the blood in the small intestine. The relative concentrations of glucose inside and outside the epithelial cell are
indicated.
Based on the model, which of the following movements does not require an input of energy?(CH5)
+
a. 𝐾 moving out of the blood and into the epithelial cell
+
b. 𝑁𝑎 moving out of the epithelial cell and into the blood
c. Glucose moves out of the epithelial cell and into the blood
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d. Glucose moves out of the intestinal lumen into an epithelial cell
11. Experimental evidence shows that the process of glycolysis is present and virtually identical in
organisms from all three domains, Archaea, Bacteria, and Eukarya. Which of the following hypotheses
could be best supported by this evidence? (CH1 and CH3)
a. All organisms carry out glycolysis in mitochondria.
b. Across the three domains, all organisms depend solely on the process of anaerobic respiration for ATP
production.
c. The presence of glycolysis as an energy-releasing process in all organisms suggests that convergent
evolution occurred.
d. Glycolysis is a universal energy-releasing process and therefore suggests a common ancestor for all
forms of life.
12. Paramecia are unicellular protists that have contractile vacuoles to remove excess intracellular water. In
an experimental investigation, paramecia were placed in salt solutions of increasing osmolarity. The rate at
which the contractile vacuole contracted to pump out excess water was determined and plotted against the
osmolarity of the solutions, as shown in the graph. Which of the following is the correct explanation for the
data? (CH5)
a. The contractile vacuole is less efficient in solutions of high osmolarity because of the reduced amount of
ATP produced from cellular respiration.
b. In an isosmotic salt solution, there is no diffusion of water into or out of the paramecia, so the
contraction rate is zero.
c. At higher osmolarity, lower rates of contraction are required because more salt diffuses into the
paramecia.
d. The contraction rate increases as the osmolarity decreases because the amount of water entering the
paramecia by osmosis increases.
13. Five new species of bacteria were discovered in Antarctic ice core samples. The nucleotide (base)
sequences of rRNA subunits were determined for the new species. The table below shows the number of
nucleotide differences between the species.
Page 4 Bio midterm review.pdf
Combined Practice /71
51 MCQs (51 points)
1. Which of the following is NOT a reason that Carl Woose and other authors of the domain article proposed
to reorganize the 6 kingdom classification system into a new system that has 3 domains as the broadest
categories (CH1)
a. Organisms in the Domain Archea were equally as different from organisms in Domain Eukarya as
they are from Domain Bacteria and therefore should be categorized in their own domain
b. Historically, life was organized based solely on morphological characteristics, however, with
recent advancements in technology, they have indicated that there are 3 distinct phylogenetic
branches in the tree of life
c. It is understood that cells have taken 3 very different paths since the occurrence of a LUCA (Last
Universal Common Ancestor) which existed about 3.8 billion years ago
d. The RNA molecules found in the organisms within the Domain Eukarya, Domain Prokarya, and
Domain Archea were all too similar to be put into 6 different kingdoms
2. Which statement about the properties of life is false (CH1)
a. Organisms can respond to their environment
b. Organisms have the ability to take in energy and use it
c. Organisms have unchanging, constant internal environments
d. Organisms have the ability to reproduce
3. In a water molecule, the hydrogen and oxygen atoms are each held together by a ______________bond. (CH2)
a. Nonpolar covalent
b. Polar Covalent
c. Hydrogen bonds
d. Double covelant
4. In a temperate forest ecosystem, both biotic and abiotic factors shape the dynamics of plant and animal
populations. The following factors are at play in this ecosystem:
● Abiotic factors: Seasonal changes in temperature, annual rainfall, soil pH, and light intensity.
● Biotic factors: Predator-prey interactions (foxes and rabbits), competition for resources (trees competing
for light, herbivores competing for plants), and mutualistic relationships (e.g., nitrogen-fixing bacteria in
the roots of plants).
Which of the following statements best describes how the interaction of biotic and abiotic factors can influence the
dynamics of this temperate forest ecosystem? (CH1)
A) Changes in soil pH can directly influence the rate of nitrogen fixation by bacteria, but they have little impact on
the plant species composition since trees and shrubs are not affected by pH levels.
B) The seasonal variation in temperature is an abiotic factor that can affect both the metabolic rates and reproductive
success of foxes and rabbits, leading to seasonal fluctuations in population size due to increased or decreased
predator-prey interactions.
C) Competition between trees for light can result in competitive exclusion, where one species of tree completely
eliminates another, and this competition is unaffected by seasonal temperature changes.
D) The mutualistic relationship between nitrogen-fixing bacteria and trees enhances soil fertility, which directly
influences the growth of herbivorous plant species, but has no impact on higher trophic levels like foxes and rabbits.
E) Abiotic factors, such as rainfall and temperature, directly influence the availability of food for herbivores like
rabbits but do not impact predator species such as foxes, because foxes are not dependent on seasonal changes for
survival.
Page 1 Bio midterm review.pdf
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5. Which of the following statements best describes the relationship between the hierarchy of life and the concept of
emergent properties? (CH1)
A) At the organ system level, the complexity of biological functions is reduced because each organ system operates
independently, without interacting with others.
B) The cellular level represents the highest level of organization in the biological hierarchy, where all functions
necessary for life are carried out. Organisms can exist at the cellular level without higher levels of organization.
C) Emergent properties, such as population growth and species interactions, arise at the population level and cannot
be predicted from the characteristics of individual organisms.
D) At the biosphere level, life processes cease to be relevant because the interaction between living organisms and
their environment leads to a lack of complexity, making ecosystems homogeneous.
6. A student used a microscope to observe a wet-mount slide of red onion epidermal cells that were suspended in a
1% NaCl solution. The student then added a 15% NaCL solution to the slide and observed the changes that occurred.
The student’s observations are represented in Figure 1. Which of the following most directly explains the changes in
the cells? (CH5)
(A) The degradation of DNA in the nuclei of the cells
(B) The lysis of chloroplasts in the cells
(C) The movement of water from the central vacuoles of the cells into the solution
(D) The movement of NaCl from the solution into the cytoplasm of the cells
7. The enzyme trypsin aids in protein digestion in the small intestine. The relative activity of trypsin at different pH
values is shown in Figure 1.
Which of the following statements best explains the activity levels of trypsin shown in Figure 1? (CH5)
(A) The small intestine releases inhibitor molecules that block the activity of trypsin unless it is at its optimum pH.
(B) The number of effective collisions between trypsin and its substrate increase at higher pH values.
(C) As pH values increase, the substrate concentration decreases, leading to an eventual decline in the rate of the
trypsin-catalyzed reaction.
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(D) At extremely low pH values, trypsin is denatured and cannot function efficiently
8. Scientists examined the folded structure of a purified protein resuspended in water. They found that amino acids
with nonpolar R groups were primarily buried in the middle of the protein. In contrast, amino acids with polar R
groups were primarily on the surface of the protein. Which of the following best explains the location of the amino
acids in the folded protein? (CH3)
(A) Polar R groups on the surface of the protein can form ionic bonds with the charged ends of the water molecules.
(B) Polar R groups are too bulky to fit in the middle of the protein and are pushed toward the protein’s surface.
(C) Nonpolar R groups that cannot form hydrogen bonds with water are pushed into the middle of the protein.
(D) Nonpolar R groups from different parts of the protein form covalent bonds with each other to maintain the
protein’s structure.
9. Which of the following best describes the R chain of this amino acid (Serine)? (CH3)
(A) Polar Uncharged
(B) Non-Polar Noncharged
(C) Polar positive charge
(D) Polar negative charge
10. The model below shows how glucose and sodium ions move between the intestinal lumen, an epithelial cell,
and the blood in the small intestine. The relative concentrations of glucose inside and outside the epithelial cell are
indicated.
Based on the model, which of the following movements does not require an input of energy?(CH5)
+
a. 𝐾 moving out of the blood and into the epithelial cell
+
b. 𝑁𝑎 moving out of the epithelial cell and into the blood
c. Glucose moves out of the epithelial cell and into the blood
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d. Glucose moves out of the intestinal lumen into an epithelial cell
11. Experimental evidence shows that the process of glycolysis is present and virtually identical in
organisms from all three domains, Archaea, Bacteria, and Eukarya. Which of the following hypotheses
could be best supported by this evidence? (CH1 and CH3)
a. All organisms carry out glycolysis in mitochondria.
b. Across the three domains, all organisms depend solely on the process of anaerobic respiration for ATP
production.
c. The presence of glycolysis as an energy-releasing process in all organisms suggests that convergent
evolution occurred.
d. Glycolysis is a universal energy-releasing process and therefore suggests a common ancestor for all
forms of life.
12. Paramecia are unicellular protists that have contractile vacuoles to remove excess intracellular water. In
an experimental investigation, paramecia were placed in salt solutions of increasing osmolarity. The rate at
which the contractile vacuole contracted to pump out excess water was determined and plotted against the
osmolarity of the solutions, as shown in the graph. Which of the following is the correct explanation for the
data? (CH5)
a. The contractile vacuole is less efficient in solutions of high osmolarity because of the reduced amount of
ATP produced from cellular respiration.
b. In an isosmotic salt solution, there is no diffusion of water into or out of the paramecia, so the
contraction rate is zero.
c. At higher osmolarity, lower rates of contraction are required because more salt diffuses into the
paramecia.
d. The contraction rate increases as the osmolarity decreases because the amount of water entering the
paramecia by osmosis increases.
13. Five new species of bacteria were discovered in Antarctic ice core samples. The nucleotide (base)
sequences of rRNA subunits were determined for the new species. The table below shows the number of
nucleotide differences between the species.
Page 4 Bio midterm review.pdf
