Free Massachusetts Tests for Educator Licensure Biology (66) Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Massachusetts Tests for Educator Licensure Biology (66) practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1Why does a pond warm more slowly than nearby dry ground under comparable solar heating?

   1. A.High specific heat capacity of liquid waterCorrect answer: A
   2. B.Low specific heat capacity of liquid water
   3. C.Low latent heat of vaporization of liquid water
   4. D.Weak intermolecular attraction in liquid water

   Explanation: OpenStax states, "Water’s high heat capacity is a property that hydrogen bonding among water molecules causes." Water requires substantial heat to change temperature because of its high specific heat capacity. Low specific heat predicts faster warming, while low vaporization heat and weak attraction do not explain strong thermal buffering.

   Reference: OpenStax Biology 2e — 2.2 Water — Water’s High Heat Capacity

2. 2Which structure most directly distinguishes a eukaryotic cell from a prokaryotic cell?

   1. A.A plasma membrane enclosing cytoplasm
   2. B.Ribosomes that synthesize proteins
   3. C.A membrane-bound nucleus containing chromosomesCorrect answer: C
   4. D.DNA that carries hereditary information

   Explanation: OpenStax states, "Unlike prokaryotic cells, eukaryotic cells have: 1) a membrane-bound nucleus;" Both cell types have membranes, ribosomes and DNA. A membrane-bound nucleus distinguishes eukaryotic organization; the distractors mistake shared cellular features for distinguishing features.

   Reference: OpenStax Biology 2e — 4 3 eukaryotic cells — Eukaryotic cells, opening comparison

3. 3In the logistic growth model, what does carrying capacity K represent?

   1. A.The greatest birth rate measured in an individual
   2. B.The number of immigrants entering each year
   3. C.The maximum population size the environment can supportCorrect answer: C
   4. D.The population's initial size before reproduction starts

   Explanation: OpenStax states, "This population size, which represents the maximum population size that a particular environment can support, is called the carrying capacity, or K." K is a supported population size, not an individual's birth rate, annual immigration count, or initial population. It can change if environmental resources change.

   Reference: OpenStax Biology 2e — 45 3 environmental limits to population growth — Carrying Capacity and the Logistic Model

4. 4After one round of semiconservative DNA replication, what is the strand composition of each daughter DNA double helix?

   1. A.Two newly synthesized strands with no parental strand
   2. B.Two parental strands with no newly synthesized strand
   3. C.Parental fragments alternating with new fragments in both strands
   4. D.One parental strand paired with one newly synthesized strandCorrect answer: D

   Explanation: OpenStax states, "after replication, each double-stranded DNA includes one parental or “old” strand and one “new” strand." Semiconservative replication preserves one complete parental strand in each daughter duplex. The other descriptions correspond to an entirely new duplex, an unchanged duplex, or the rejected dispersive model.

   Reference: OpenStax Biology 2e — 14 3 basics of dna replication — Models of DNA replication

5. 5Students model a double-stranded DNA molecule containing 30% adenine among all its nucleotides. Which guanine percentage makes the model consistent with complementary base pairing?

   1. A.10%
   2. B.30%
   3. C.20%Correct answer: C
   4. D.40%

   Explanation: OpenStax states, "A pairs with T, and G pairs with C" A = T = 30%, leaving 100 − 60 = 40% for G + C. Since G = C, G = 40/2 = 20%, with no rounding. Ten divides the remaining fraction twice; thirty assumes all base classes match A; forty fails to split G + C.

   Reference: OpenStax Biology 2e — 14 2 dna structure and sequencing — DNA double-helix base pairing

6. 6At the same temperature, solution X has pH 5 and solution Y has pH 7. How does the hydrogen-ion concentration in X compare with that in Y?

   1. A.It is 2 times as high.
   2. B.It is 20 times as high.
   3. C.It is 100 times as high.Correct answer: C
   4. D.It is 100 times as low.

   Explanation: OpenStax states, "We calculate the pH as the negative of the base 10 logarithm of this concentration." [H+]X/[H+]Y = 10^-5/10^-7 = 10^2 = 100 (dimensionless), with no rounding. Two treats pH as linear; twenty incorrectly multiplies two units by ten; one hundred times lower reverses the logarithmic relationship.

   Reference: OpenStax Biology 2e — 2.2 Water — pH, Buffers, Acids, and Bases

7. 7A macrophage engulfs bacteria into a membrane-bound compartment. Which organelles supply hydrolytic enzymes that help digest the engulfed material?

   1. A.LysosomesCorrect answer: A
   2. B.Centrosomes
   3. C.Nucleoli
   4. D.Mitochondria

   Explanation: OpenStax states, "Enzymes within the lysosomes aid in breaking down proteins, polysaccharides, lipids, nucleic acids, and even worn-out organelles." Lysosomes carry digestive hydrolases. Centrosomes organize microtubules, nucleoli assemble ribosomal subunits, and mitochondria support respiration rather than serving as the digestive compartment.

   Reference: OpenStax Biology 2e — 4 3 eukaryotic cells — Lysosomes

8. 8Seedlings of the same tree species grow in a crowded patch and compete for light and water. Which interaction is illustrated?

   1. A.Intraspecific competitionCorrect answer: A
   2. B.Interspecific competition
   3. C.Predation
   4. D.Commensalism

   Explanation: OpenStax states, "The resulting competition between population members of the same species for resources is termed intraspecific competition" Same-species competition is intraspecific. Interspecific competition is between species, predation involves consumption of prey, and commensalism benefits one species without affecting the other.

   Reference: OpenStax Biology 2e — 45 3 environmental limits to population growth — Carrying Capacity and the Logistic Model

9. 9Which activity of DNA ligase completes the continuity of the lagging-strand backbone after RNA primers have been replaced?

   1. A.Unwinding the parental double helix at the fork
   2. B.Adding the first RNA nucleotides of a new primer
   3. C.Sealing nicks by forming phosphodiester bondsCorrect answer: C
   4. D.Removing supercoils ahead of the replication fork

   Explanation: OpenStax states, "The gap between the two DNA fragments is sealed by DNA ligase, which helps in the formation of phosphodiester bonds." Ligase joins backbone ends. Helicase unwinds DNA, primase makes RNA primers, and topoisomerase relieves supercoiling; these are related replication tasks but do not seal the remaining nick.

   Reference: OpenStax Biology 2e — 14 4 dna replication in prokaryotes — DNA replication in prokaryotes, elongation

10. 10In a classroom model, ATP is hydrolyzed to ADP and phosphate during work. Which addition is required to represent the regeneration of ATP accurately?

    1. A.An energy input driving the joining of ADP and phosphateCorrect answer: A
    2. B.An energy output driving the joining of ADP and phosphate
    3. C.A catalyst lowering the barrier without any input of energy
    4. D.A closed cycle that regenerates ATP using only its own hydrolysis

    Explanation: OpenStax states, "Since ATP hydrolysis releases energy, ATP regeneration must require an input of free energy." ATP regeneration needs an energy input to drive ADP-plus-phosphate synthesis. Net energy output reverses the energetics; a catalyst alone cannot supply free energy, and hydrolysis cannot power lossless perpetual regeneration.

    Reference: OpenStax Biology 2e — 6 4 atp adenosine triphosphate — ATP regeneration