Which of these is NOT a monomer used to build a biological polymer?
Glycerol
✓
Amino acid
Nucleotide
Glucose
Correct Answer
Glycerol
Amino acids, nucleotides, and glucose are monomers that form long polymer chains (proteins, nucleic acids, polysaccharides, respectively). Glycerol is a component of lipids (triglycerides), but lipids are not true polymers made of repeating monomer units in the same way.
Question 2
Which of these organelles is NOT part of the endomembrane system?
Golgi apparatus
Lysosome
Endoplasmic Reticulum
Mitochondrion
✓
Correct Answer
Mitochondrion
The endoplasmic reticulum, Golgi apparatus, and lysosomes are all components of the endomembrane system, which is involved in protein and lipid synthesis, modification, and transport. Mitochondria are involved in cellular respiration and are not part of the endomembrane system.
Question 3
Three of these processes take place inside the mitochondrion. Which one does not?
Glycolysis
✓
Pyruvate oxidation
Electron transport chain
Krebs cycle
Correct Answer
Glycolysis
Pyruvate oxidation, the Krebs cycle, and the electron transport chain all occur within the mitochondria of a eukaryotic cell. Glycolysis is the only process listed that occurs in the cytoplasm.
Question 4
Three of these events occur only in meiosis. Which one does not?
Crossing over
Synapsis of homologous chromosomes
Sister chromatids separate
✓
Reduction of chromosome number
Correct Answer
Sister chromatids separate
Synapsis of homologous chromosomes, crossing over, and the reduction of chromosome number are events unique to meiosis. Sister chromatids separate in both anaphase of mitosis and anaphase II of meiosis.
Question 5
Three of these RNA molecules are non-coding. Which one is not?
snRNA
rRNA
mRNA
✓
tRNA
Correct Answer
mRNA
tRNA, rRNA, and snRNA all play roles in gene expression but do not primarily carry the genetic code sequence from DNA to the ribosome. mRNA (messenger RNA) is specifically responsible for carrying this genetic code.
Question 6
Which of these is NOT considered direct evidence for evolution by natural selection?
Fossil record
Comparative anatomy
Acclimatization
✓
DNA sequencing
Correct Answer
Acclimatization
The fossil record, comparative anatomy (homologous structures), and DNA sequencing (molecular homology) provide strong evidence for evolutionary change and descent with modification. Acclimatization is a short-term physiological adjustment by an individual to environmental changes and is not an inheritable evolutionary change in a population.
Question 7
Which of these elements does not have a significant atmospheric gaseous phase in its biogeochemical cycle?
Carbon
Nitrogen
Phosphorus
✓
Sulfur
Correct Answer
Phosphorus
Sulfur (as SO2, H2S), Carbon (as CO2), and Nitrogen (as N2, N2O) all have significant gaseous phases in their respective biogeochemical cycles. The phosphorus cycle is primarily sedimentary, involving rocks, soil, water, and living organisms, with no significant atmospheric gaseous phase.
Question 8
Which of these properties of water is NOT primarily due to hydrogen bonding?
Low molecular weight
✓
Cohesion
Adhesion
High specific heat
Correct Answer
Low molecular weight
High specific heat, cohesion, and adhesion are all emergent properties of water that result from the extensive hydrogen bonding between water molecules. Low molecular weight is an intrinsic property of the H2O molecule itself, determined by the atomic masses of hydrogen and oxygen, not by intermolecular forces.
Question 9
Three of these transport mechanisms are passive. Which one is not?
Simple diffusion
Active transport
✓
Facilitated diffusion
Osmosis
Correct Answer
Active transport
Facilitated diffusion, osmosis, and simple diffusion are all forms of passive transport that do not require direct cellular energy (ATP) input, relying instead on concentration gradients. Active transport is the only mechanism listed that directly uses ATP to move substances against their concentration gradient.
Question 10
Which of these is NOT a direct product of the light-dependent reactions of photosynthesis?
NADPH
Oxygen
ATP
Glucose
✓
Correct Answer
Glucose
ATP, NADPH, and Oxygen are all direct products of the light-dependent reactions of photosynthesis. Glucose is produced during the light-independent reactions (Calvin cycle), utilizing the ATP and NADPH generated by the light-dependent reactions.
Question 11
Three of these inheritance patterns produce a heterozygous phenotype distinct from the homozygous dominant. Which one does not?
Incomplete dominance
Complete dominance
✓
Multiple alleles
Codominance
Correct Answer
Complete dominance
Incomplete dominance, codominance, and multiple alleles describe inheritance patterns where the heterozygote phenotype is either intermediate, expresses both alleles, or involves more than two alleles for a trait, respectively, and is distinct from the homozygous dominant phenotype. Complete dominance is the specific pattern where the heterozygous phenotype is indistinguishable from the homozygous dominant phenotype.
Question 12
Which of these is NOT a common mechanism of gene regulation in eukaryotes?
RNA interference
Chromatin modification
Post-translational modification
Operons
✓
Correct Answer
Operons
Chromatin modification, RNA interference, and post-translational modification are all significant mechanisms of gene regulation in eukaryotes. Operons are clusters of genes under the control of a single promoter and are characteristic mechanisms of gene regulation primarily in prokaryotes.
Question 13
Which of these types of natural selection does NOT typically lead to a shift in the mean phenotype of a population over time?
Stabilizing selection
✓
Directional selection
Sexual selection
Disruptive selection
Correct Answer
Stabilizing selection
Directional selection, disruptive selection, and sexual selection can all lead to a shift in the mean phenotype or a change in the phenotypic distribution of a population over time. Stabilizing selection, by favoring intermediate phenotypes, typically acts to maintain the mean phenotype and reduce phenotypic variation around that mean.
Question 14
Which of these factors is NOT typically density-dependent in regulating population growth?
Disease
Natural disaster
✓
Competition
Predation
Correct Answer
Natural disaster
Disease, predation, and competition are all density-dependent factors, meaning their impact on population growth intensifies as population density increases. Natural disasters (e.g., floods, fires, extreme weather) are typically density-independent factors, affecting populations regardless of their density.
Question 15
Three of these are intramolecular bonds within a single molecule. Which one is not?
Ionic bond
Hydrogen bond
✓
Covalent bond
Peptide bond
Correct Answer
Hydrogen bond
Covalent bonds, ionic bonds, and peptide bonds are strong intramolecular bonds that hold atoms together within a molecule. Hydrogen bonds are weaker interactions that typically occur between separate molecules (intermolecular) or between different parts of a large molecule (intramolecular, but still weaker than covalent).