Name __________________________________________________​ ​ ​ Class Period ________

Biology Practice Final Exam: Spring 2025

[Version #1]

1. The graph for an aquatic ecosystem below BEST supports the idea 5. Below is a pedigree for an autosomal dominant trait.
that…

A.​ If some nutrients are significantly increased, rapid growth of

If two individuals were crossed, and these two individuals had the same
certain organisms can negatively impact others
genotypes as individuals I-2 and II-1 in this pedigree, what would be the
B.​ The increase of any nutrient within an ecosystem will result in
likelihood that they would produce an offspring with the dominant
increased growth of the organisms in that ecosystem
phenotype two times in a row?
C.​ Sea grasses are unable to survive in environments that contain
A. 1/16​ B. 1/8​ C. 3/16​ D. 9/16 E. 1/4
high levels of nutrients
D.​ Organisms with smaller biomasses are not generally affected by
6. Which of the following ideas in Darwin’s theory most clearly reflects
nutrient levels in their environment
the influence of geologists like Hutton and Lyell?
E.​ The presence of sea grasses kept the macroalgae population
A.​ All species were created in their current forms and remain
limited, but the disappearance of most sea grasses then allowed
unchanged.
macroalgae to flourish
B.​ Evolution proceeds through sudden, rapid changes after mass
extinctions.
2. If you were exposed to a toxin that irreversibly blocked any sodium
C.​ Gradual change over vast time periods can result in major
channels found on nerve cells, which effect below would most likely
biological differences.
occur?
D.​ Favorable traits acquired during an organism’s lifetime are
A.​ Increased levels of neurotransmitters released
inherited by offspring.
B.​ After an action potential occurs, the membrane is unable to
E.​ Variation within a population leads to competition and struggle
reset back to its resting potential
for existence.
C.​ Slowly conduction of positive charges down the axon
D.​ Inability to begin any action potentials
7. A farmer grows both xerophytic and hydrophytic plants in adjacent
E.​ Inability to conduct synaptic signaling
fields. Which of the following adaptations would be most expected in the
xerophytes but not the hydrophytes?
3. A mutation alters the structure of a eukaryotic promoter region but
A.​ Broad, flat leaves to maximize light capture
leaves the gene's coding region unchanged. Which of the following
B.​ Reduced leaf surface area and thick cuticles
would most likely result?
C.​ Shallow root systems that absorb surface water
A.​ The gene will be transcribed but not translated due to a
D.​ Large air spaces in stem tissues
defective ribosome binding site.
E.​ High stomatal density for gas exchange
B.​ The gene will be overexpressed due to loss of epigenetic
controls.
8. A particular ranch often conducts genetic testing of newly born
C.​ Transcription will not initiate properly, reducing or eliminating
animals to ensure their records of the offspring’s parents are correct.
protein production.
Samples of a recently born female horse, its mother, and four of the
D.​ Translation will begin earlier than normal, producing a
possible male parents were taken and tested. Gel electrophoresis results
nonfunctional protein.
are shown below. Based on this,
E.​ The gene will be spliced incorrectly, resulting in an altered
which of these horses was likely
mRNA sequence.
the male parent for this offspring?
A.​ Horse #1
4. In mice, yellow fur is dominant over white fur. The yellow fur allele is
B.​ Horse #2
also recessively lethal. If a yellow mouse and a white mouse mate, what
C.​ Horse #3
percent of their offspring would you expect to be white?
D.​ Horse #4
A. 0% B. 25% C. 33% D. 50% E. 66%
E.​ None of these are
possible
9. Each image below shows a cross-section of the small intestines, but 18. Alternative splicing allows…
each picture comes from a different animal species. Which of these A.​ Changing of the DNA sequence in some portions of a gene
animals would likely be able to absorb B.​ Alterations to the poly-A tail and cap found on mRNA
the LEAST amount of nutrition per C.​ Use of different ribosomes to conduct translation
centimeter of intestine length? D.​ Removal of different combinations of exons
A.​ Organism G E.​ One promoter to control multiple different DNA sequences
B.​ Organism F
C.​ Organism J 19. Which of the following sequences correctly represents the steps
D.​ Organism H during a single cycle of muscle contraction?
A.​ ATP binds myosin → calcium binds troponin → power stroke
→ myosin releases ADP + phosphate
For questions 10 - 13, bubble “A” if that statement is TRUE and B.​ Calcium binds troponin → myosin releases ADP + phosphate
“B” if the statement is FALSE. → power stroke → ATP binds myosin
C.​ Calcium binds troponin → ATP binds myosin → power stroke
10. The main function of a plant’s stamen is to produce pollen. → myosin releases ADP + phosphate
D.​ Myosin releases ADP + phosphate → ATP binds myosin →
11. The left atrium of the heart contains blood with a lower oxygen calcium binds troponin → power stroke
concentration than the right atrium of the heart. E.​ ATP binds myosin → power stroke → calcium binds troponin
→ myosin releases ADP + phosphate
12. The lagging strand is synthesized in the 3’ to 5’ direction during
DNA replication because DNA polymerase can’t read backwards. 20. Two closely related finch species live on the same island but feed on
different seed sizes. Over time, their beak sizes become very different.
13. A keystone species has a larger effect on ecosystem stability than Which concept best explains this?
might be predicted based on its abundance. A.​ Convergent evolution producing similar traits in unrelated
species
14. Scientists believe that the first types of cells to appear were… B.​ Genetic drift causing random changes in beak size frequencies
A. Aerobic & Prokaryotic​ B. Aerobic & Eukaryotic C.​ Adaptive radiation leading to new species filling different niches
C. Anaerobic & Prokaryotic​ D. Anaerobic & Eukaryotic D.​ Competitive exclusion forcing species to use separate resources
E. Anaerobic & Protists E.​ Divergent evolution causing differences due to resource use

15. Two genetically identical plants are grown in different environments. 21. A frameshift mutation occurs early in a gene coding region. Which
One grows rapidly and flowers early; the other remains stunted and outcome is most likely?
delays flowering. Genetic sequencing reveals no mutations. Which A.​ A completely different amino acid sequence downstream
mechanism most likely explains the difference? B.​ The protein sequence remains mostly unchanged
A.​ Accumulated mutations altered flowering gene sequences. C.​ No effect because the mutation is silent
B.​ Disruptions in the promoter region halted DNA replication. D.​ A single amino acid substitution at the mutation site
C.​ Ribosomal RNA failed to assemble correctly in one plant. E.​ The mutation affects only non-coding regions
D.​ Silent mutations in tRNA genes disrupted protein synthesis.
E.​ Epigenetic modifications changed gene expression patterns. 22. During a fetal pig dissection in class, a student finds a blood vessel.
When she pulls on it, it snaps back and seems to be quite elastic. It also
16. Which graph below best represents the relationships between trophic looks like the walls of the vessel are thicker than many others within the
levels and available energy, in an ecosystem? body. What kind of blood vessel is this most likely to be?
A. ​ ​ B. ​ ​ C. D. ​ A. Artery​ B. Capillary​ C. Vein
​ ​ D. Cranial​ E. Lymphatic

23. Which of the following would likely involve a change in a

population’s allele frequencies?
17. Which statement best describes the evolutionary consequence of
mass extinctions? #1 - Founder Effect #2 - Bottleneck Effect #3 - Evolution
A.​ They slow evolution by eliminating genetic diversity. ​ A. #1 only​ B. #2 only​ C. #3 only
B.​ They result in stabilizing selection maintaining existing traits. ​ D. #1 & #2 only​ E. #1, #2, & #3
C.​ They prevent speciation by reducing population sizes
permanently.
D.​ They create opportunities for adaptive radiation among
survivors.
E.​ They increase the frequency of recessive alleles by random
chance.
 29. In humans, the really cool trait (R) is dominant over the not cool trait
For questions 24 - 26, use the following word bank: (r). In a group of students, 350 are not cool and 1100 are really cool.
A. hormone B. antigen C. glycoprotein What number of students in this group would likely be heterozygous for
D. envelope E. incomplete dominance AB. polygenic this trait? Assume the population is in H-W equilibrium.
AC. antibody AD. epigenetic AE. capsid A. 479 students B. 631 students C. 529 students
BC. aneuploidy BD. cell membrane BE. linked genes ​ ​ D. 725 students​ E. 550 students

24. This specialized protein is released by plasma cells. 30. Which term would fit best in the “X” spot on the diagram below?
25. A layer that surrounds some, but not all, viruses. A.​ Respiration
B.​ Combustion
26. A trait in which multiple genes contribute additively to the C.​ Photosynthesis
expression of the single trait. D.​ Transpiration
E.​ Sedimentation
27. A DNA sequence reads: 3′ – GGTACGGATTTACC – 5′
The sequence mutates to become: 3′ – GGTACGAATTTACC – 5′
Which of the following best describes the functional outcome of this
mutation?
A.​ The resulting protein is unchanged despite the DNA change
B.​ One amino acid is altered, which may affect protein function
C.​ A premature stop codon is introduced, truncating the protein
D.​ All amino acids downstream of the mutation are changed
E.​ The ribosome is unable to initiate translation at all

28. A patient, Samantha, is currently in the hospital and in need of a

blood transfusion. Unfortunately, the hospital recently experienced a
major electrical malfunction making it impossible to conduct any lab
tests and rendering all previously stored blood useless. The doctor speaks
with Samantha’s family to see if any of them might be a suitable donor.
Samantha’s mom shares some old medical documents with the doctor.
From these, he is able to figure out that Samantha has Type O+ blood,
her mom has Type A- blood, and Jack (Samantha’s younger brother) has
Type B+ blood. Samantha’s father has not had his blood tested before, so
his blood type is unknown.
Which conclusion would be most reasonable for the doctor to make?
A.​ Samantha would be able to safely receive transfusions from
both her mother and father, but not from Jack.
B.​ Jack is a compatible donor for Samantha since they share the
same Rh factor.
C.​ Samantha’s mom cannot donate to her, due to the absence of
the Rh factor in her blood.
D.​ Samantha cannot receive a transfusion from her father, due to
the presence of B antigens in his blood.
E.​ Both Jack and her father can donate blood to her, because all
three of them are Rh positive.