Name: ____________________________________________________
Date: ___/___/___
Period: ____
Keystone Practice Questions
1. D____ Living organisms can be classified as prokaryotes or eukaryotes. Which two structures are common
to both prokaryotic and eukaryotic cells?
A. cell wall and nucleus
B. cell wall and chloroplast
C. plasma membrane and nucleus
D. plasma membrane and cytoplasm
2. D____ Alveoli are microscopic air sacs in the lungs of mammals. Which statement best describes how the
structure of the alveoli allows the lungs to function properly?
A. They increase the amount of energy transferred from the lungs to the blood.
B. They increase the flexibility of the lungs as they expand during inhalation.
C. They increase the volume of the lungs, allowing more oxygen to be inhaled.
D. They increase the surface area of the lungs, allowing efficient gas exchange.
3. C____ Which statement best describes an effect of the low density of frozen water in a lake?
A. When water freezes, it contracts, decreasing the water level in a lake.
B. Water in a lake freezes from the bottom up, killing most aquatic organisms.
C. When water in a lake freezes, it floats, providing insulation for organisms below.
D. Water removes thermal energy from the land around a lake, causing the lake to freeze.
4. B____ Carbohydrates and proteins are two types of macromolecules. Which functional characteristic of
proteins distinguishes them from carbohydrates?
A. large amount of stored information
B. ability to catalyze biochemical reactions
C. efficient storage of usable chemical energy
D. tendency to make cell membranes hydrophobic
5. B____ Using a microscope, a student observes a small, green organelle in a plant cell. Which energy
transformation most likely occurs first within the observed organelle?
A. ATP to light
B. light to chemical
C. heat to electrical
D. chemical to chemical
6. B___ Photosynthesis and cellular respiration are two major processes of carbon cycling in living organisms.
Which statement correctly describes one similarity between photosynthesis and cellular respiration?
A. Both occur in animal and plant cells.
B. Both include reactions that transform energy.
C. Both convert light energy into chemical energy.
D. Both synthesize organic molecules as end products.
7. A____ A protein in a cell membrane changed its shape to move sodium and potassium ions against their
concentration gradients. Which molecule was most likely used by the protein as an energy source?
A. ATP
B. ADP
C. catalase
D. amylase
8. B____ Carbon dioxide and oxygen are molecules that can move freely across a plasma membrane. What
determines the direction that carbon dioxide and oxygen molecules move?
A. orientation of cholesterol in the plasma membrane
B. concentration gradient across the plasma membrane
C. configuration of phospholipids in the plasma membrane
D. location of receptors on the surface of the plasma membrane
9. B____ A sodium-potassium pump within a cell membrane requires energy to move sodium and potassium
ions into or out of a cell. The movement of glucose into or out of a cell does not require energy. Which
statement best describes the movement of these materials across a cell membrane?
A. Sodium and potassium ions move by active transport, and glucose moves by osmosis.
B. Sodium and potassium ions move by active transport, and glucose moves by facilitated diffusion.
C. Sodium and potassium ions move by facilitated diffusion, and glucose moves by osmosis.
D. Sodium and potassium ions move by facilitated diffusion, and glucose moves by active transport.
10. D____ Mitosis and meiosis are processes by which animal and plant cells divide. Which statement best
describes a difference between mitosis and meiosis?
A. Meiosis is a multi-step process.
B. Mitosis occurs only in eukaryotic cells.
C. Meiosis is used in the repair of an organism.
D. Mitosis produces genetically identical daughter cells.
11. D____ In a flowering plant species, red flower color is dominant over white flower color. What is the
genotype of any red-flowering plant resulting from this species?
A. red and white alleles present on one chromosome
B. red and white alleles present on two chromosomes
C. a red allele present on both homologous chromosomes
D. a red allele present on at least one of two homologous chromosomes
Use the table below to answer the question.
Blood Types
Genotypes(s)
Phenotype
ii
O
A A A
A
I I ,I i
B B B
B
I I ,I i
A B
AB
I I
12. D____ Blood type is inherited through multiple alleles, including IA, IB, and i. A child has type A blood. If the
father has type AB blood, what are all the possible phenotypes of the mother?
A. phenotypes O or A
B. phenotypes A or AB
C. phenotypes A, B, AB
D. phenotypes O, A, B, AB
Use the diagram below to answer the question.
13. D____ Which type of change in chromosome composition is illustrated in the diagram?
A. deletion
B. insertion
C. inversion
D. translocation
Use the circle graphs below to answer the question.
14. B____ The graphs illustrate change in a lizard population over time. Which process most likely led to the
change in the lizard population?
A. natural selection acting on a harmful trait
B. natural selection acting on a beneficial trait
C. natural selection acting on a dominant trait
D. natural selection acting on a recessive trait
Use the table below to answer the question.
Student's Observations of a Pond Ecosystem
Quantitative
37 fish and 3 frogs
2 types of aquatic grass
12 small rocks and 1 medium rock
sand
Qualitative
Leaves lie on the bottom of the pond.
Water insects move along the water's surface.
All 3 frogs are sitting on a pond bank.
15. D____ A group of students measured a ten-square-meter section of a pond ecosystem and recorded
observations. Which statement is a testable hypothesis?
A. The frogs living in the pond represent a population.
B. Water is an abiotic component in the pond ecosystem.
C. If the fish are given more food, then they will be happier.
D. If the frogs are startled, then they will jump into the water.
Use the list below to answer the question.
Observations
• two grey wolves
• five moose
• several species of conifer trees
• large granite rock
• shallow pond
16. C____ A student wrote several observations in a field notebook. Which term best classifies all of the
student’s observations?
A. population
B. food chain
C. ecosystem
D. community
17. A____ A species of snapping turtles has a tongue that resembles a worm. The tongue is used to attract
small fish. Which best describes the interaction between the fish and the snapping turtle?
A. predation
B. symbiosis
C. parasitism
D. competition
18. B____ A farmer observed that an increase in a field’s soil nitrogen content was followed by an increase in
producer productivity. What does this observation most likely indicate about the relationship between nitrogen
and the producers in the field?
A. Nitrogen was a biotic factor.
B. Nitrogen was a limiting factor.
C. Nitrogen became a surplus resource.
D. Nitrogen became a selection pressure.
19. A____ Which of the following characteristics of living things explains why birds fly south for the winter?
A. Living things respond to their environment
B. Living things maintain homeostasis
C. Living things are made of cells
D. Living things are based on a universal genetic code
20. B_____ Cells in multicellular organisms have many sizes and shapes. These differences are referred to as
cell specialization. Cell specialization allows cells to:
A. Reproduce
B. Perform different functions
C. Respond to their environment
D. Be less complex
21. C_____ Which of the following answers is not a characteristic of life?
A. Made up of cells
B. Reproduction
C. Performs photosynthesis
D. Uses Energy
22. A____ In order for cells to divide successfully, the cell must first do what?
A. Duplicate its genetic information
B. Decrease its volume
C. Increase its number of chromosomes
D. Decrease its number of organelles
23. B____ An ecologist company is looking at an ecosystem where a certain bug species has gone extinct and
the role that species played in the environment. What is the role of that species of insect also known as?
A. Abiotic Factor
B. Niche
C. Biotic Factor
D. Hardy-Weinberg Equilibrium
24. C____ Darwin observed many species of finches on the Galapagos islands. In his book, On the Origin of
Species, Darwin described the process that created so many different types of finches from one common
ancestor of species. What is that process called?
A. Carrying Capacity
B. Energy Conversion
C. Natural Selection
D. Artificial Selection
25. A_____ Which of the following organizational levels includes all of the other levels?
A. Biosphere
B. Ecosystem
C. Organism
D. Cell
E. Organ
26. A_____ The most excess hydrogen ions would be found in which solution?
A. 2.5
B. 4.4
C. 7.35
D. 8.2
E. 12
27. B_____ DNA does not have:
A. Adenine
B. Uracil
C. Thymine
D. Guanine
E. Cytosine
28. B_____ The basic structural and functional unit of life:
A. Molecule
B. Cell
C. Tissue
D. Organ
E. Atom
29. C_____ DNA is in an orderly sequence of:
A. Lipids
B. Fatty acids
C. Nucleic acids
D. Amino acids
E. Monosaccharides
30. E_____ DNA replicates during:
A. Metaphase
B. Prophase
C. Telophase
D. Anaphase
E. Interphase
31. D_____ Nuclear division to form daughter cells which are genetically identical to the parent cell:
A. Meiosis
B. Cytokinesis
C. Interphase
D. Mitosis
E. Fission
32. A_____ The plasma membrane is considered to be:
A. Semipermeable
B. Impermeable
C. Permeable
D. Selectively permeable
E. Non-permeable
33. B_____ The process of transcription does not directly use:
A. DNA
B. tRNA
C. mRNA
D. Enzymes
34. D_____ The hydrophobic region of the plasma membrane is:
A. Phosphate head groups
B. Faces the intracellular compartment
C. Polar
D. Lipid tail groups
35. A_____ This process does not occur in the nucleus:
A. Translation
B. DNA "unzipping" to form the DNA template
C. Transcription
D. DNA replication
36. D_____ Evolution is considered…
A. Pertains to populations, not individuals.
B. Is a change in allele frequencies over time.
C. Is dependent on the variation produced by mutations in the DNA.
D. All of the above
37. C_____ Among rhinos, horn length is under the control of a single phenotype. The dominant trait yields
a longer horn while the recessive trait yields a shorter horn. What are the chances of the offspring
have a long horn if both the parents are heterozygous?
A. 25%
B. 50%
C. 75%
D. 100%
38. C_____ The Principle of dominance states that…
A. All alleles are dominant
B. All alleles are recessive
C. Some alleles are dominant to other alleles
D. Alleles are neither dominant nor recessive
39. C_____ Gametes are produced by the process of…
A. Mitosis
B. Crossing-over
C. Meiosis
D. Replication
40. B_____ Unlike mitosis, meiosis results in the formation of…
A. Diploid Cells
B. Haploid Cells
C. 2n daughter cells
D. Body Cells
41. B_____ The peppered moth comes in 2 varieties: dark-colored and light-colored. It is preyed upon by birds.
Which of the following populations would you expect to be most common if the environment is of a dark
color?
A. A population of light-colored moths
B. A population of dark-colored moths
C. Neither: there would be an equal number of both of these moth varieties
D. Neither: both moth populations would go extinct
42. D___ Which list represents the levels of organization in a multicellular organism from the simplest
level to the most complex level?
A. tissue, cell, organ system
B. organ system, organ, tissue, cell
C. cell, tissue, organism, organ system
D. cell, tissue, organ, organ system
43. B___ You are walking down the “tough streets” of Bellefonte, and suddenly you feel the need to
run away from a sasquatch! Your muscles keep a form of energy stored just for these
emergencies. What macromolecule stores energy in the muscles?
A. Chitin
B. Glucose
C. Amino Acid
D. Nucleic Acid
44. C___ Which of the following is NOT an organic compound?
A. C6H12O6
B. CH4
C. NH3
D. C2H4O2
45. D___ Which of the following represents the correct ranking of terms from smallest to largest
A. Polymer  monomer  macromolecule  carbon atom
B. Carbon atom  macromolecule  polymer  monomer
C. Monomer  carbon atom  macromolecule  polymer
D. Carbon atom  monomer  polymer  macromolecule
46. D___ While studying a cell with the electron microscope, a scientist notes the following: numerous
ribosomes, a well-developed endoplasmic reticulum, chloroplasts, and a cell wall. Which of the
following could be the source of this cell?
A. A fungus
B. An animal
C. A bacterium
D. A plant
E. A virus
47. A___ The suffix “ose” refers to _______.
A. Sugar
B. Molecule
C. Enzyme
D. Monomer
48. C___ The suffix “ase” refers to _______.
A. Sugar
B. Molecule
C. Enzyme
D. Monomer
49. B___ Monomer is to polymer as amino acid is to _________.
A. Lipids
B. Proteins
C. Fats
D. Sugars
50. A_____ If a mother has a homozygous recessive genotype, what is the chance she will give a
dominant allele to her offspring?
A. 0%
B. 25%
C. 50%
D. 100%
51. D___ The term anaerobic means
A. Without CO2
B. Without ATP
C. With O2
D. Without O2
52. D___ Which of the following correctly matches a structure with its function?
A. Mitochondria—photosynthesis
B. Nucleus— digestion
C. Vacuole— movement
D. Lysosome—digestion
53. B____ Which of the following molecules is a high energy molecule the body uses for power?
A. ADP
B. ATP
C. Mitochondria
D. Vacuole
54. D_____ Scientists use a system of classification called taxonomy to organize all of the species on
Earth. Which of the following groups is the least specific classification group?
A. Phylum
B. Species
C. Family
D. Domain
55. B_____ Similar organisms that can reproduce by and create fertile offspring belong to the same
A. Ecosystem
B. Species
C. Environment
D. Habitat
56. C_____ Which of the following is a reactant in photosynthesis?
A. O2
B. C6H12O6
C. CO2
D. COOH
57. B_____ Which statement describes the chromosome shown in the figure to the right?
A. It is made up of two histones
B. It is made up of two chromatids
C. It is made up of two centromeres
D. It is made up of two alleles
58. A_____ Which organism is capable of reproduction through asexual mitosis?
A. Bacterium
B. Horse
C. Oak tree
D. Clownfish
59. D_____ Which of the following cells is haploid?
A. Skin Cell
B. Liver Cell
C. Stomach Cell
D. Sex Cell
60. _____ Who is going to pass their biology keystone?
A. You are!
B. You!
C. Look in a mirror!
D. Me! #bioswag!