NYSTCE NYSTCE Biology (006) 5 — Questions and Answers
Question 1: Which molecule serves as the primary energy currency of the cell?
- NADH
- FADH2
- ATP (Correct answer)
- Glucose
Correct answer: ATP
ATP (adenosine triphosphate) is the universal energy currency used to power cellular processes by releasing energy when hydrolyzed to ADP.
Question 2: The Hardy-Weinberg principle states that allele frequencies in a population remain constant if which condition is met?
- The population is small and isolated
- Mutations occur at a high rate
- Mating is random and no evolutionary forces are acting (Correct answer)
- Natural selection strongly favors one allele
Correct answer: Mating is random and no evolutionary forces are acting
Hardy-Weinberg equilibrium requires random mating, large population size, no mutation, no gene flow, and no natural selection.
Question 3: Which of the following best describes convergent evolution?
- Two species diverge from a common ancestor into different niches
- Unrelated species independently evolve similar traits due to similar selective pressures (Correct answer)
- Closely related species evolve rapidly in response to each other
- A single species splits into two reproductively isolated populations
Correct answer: Unrelated species independently evolve similar traits due to similar selective pressures
Convergent evolution occurs when unrelated organisms develop similar adaptations independently, such as wings in birds and insects.
Question 4: In the human immune system, which cells are responsible for producing antibodies?
- T-helper cells
- Cytotoxic T cells
- Natural killer cells
- Plasma cells (effector B cells) (Correct answer)
Correct answer: Plasma cells (effector B cells)
Plasma cells are differentiated B lymphocytes that secrete large quantities of antigen-specific antibodies.
Question 5: A researcher finds a fossil of an organism with both reptilian and avian features. This type of fossil is best described as a:
- Index fossil
- Transitional fossil (Correct answer)
- Trace fossil
- Cast fossil
Correct answer: Transitional fossil
Transitional fossils show intermediate features between ancestral and derived groups, supporting evolutionary relationships between taxa.
Question 6: Which level of protein structure refers to the overall three-dimensional shape of a single polypeptide chain?
- Primary structure
- Secondary structure
- Tertiary structure (Correct answer)
- Quaternary structure
Correct answer: Tertiary structure
Tertiary structure is the complete 3D conformation of a single polypeptide, stabilized by interactions among R-groups including disulfide bonds and hydrophobic interactions.
Question 7: Which of the following is an example of a density-dependent limiting factor for a population?
- A volcanic eruption destroying habitat
- A severe drought affecting the entire region
- Disease spreading more rapidly as population size increases (Correct answer)
- A wildfire reducing available resources uniformly
Correct answer: Disease spreading more rapidly as population size increases
Disease transmission increases with population density, making it a density-dependent factor that has a greater effect as population size grows.
NYSTCE NYSTCE Biology (006) 5
Which molecule serves as the primary energy currency of the cell?