Biology STAAR Review: Key Concepts and Questions

What distinguishes a prokaryotic cell from a eukaryotic cell?

• Presence of a cell membrane

• Absence of a nucleus

• Presence of ribosomes

• Presence of chromosomes

What is an insertion mutation?

• Replacement of one base with another

• Removal of a base from the DNA sequence

• Addition of an extra base into the DNA sequence

• None of the above

What is the result of a point mutation in DNA?

• The removal of a base pair

• The addition of a new gene

• No change in the amino acid sequence

• A change in a single amino acid

Which ecological relationship benefits one organism while the other is unaffected?

• Competition

• Commensalism

• Parasitism

• Predation

What is essential for photosynthesis to occur?

• All of the above

• Sunlight

• Water

• Carbon dioxide

What is the likely effect of removing plateau pikas from their ecosystem?

• No significant change

• Increased grassland stability

• Decreased predator diversity

• Increased flooding due to lack of burrows

What is the outcome of gene flow between populations?

• Reduced population size

• Increased genetic diversity

• Decreased genetic diversity

• Unchanged genetic diversity

What is the primary role of lymph nodes in the immune system?

• Producing red blood cells

• Capturing harmful materials

• Regulating body temperature

• Storing excess nutrients

What happens to the ocean's ability to act as a carbon sink with increased atmospheric temperatures?

• Increases significantly

• Decreases

• Remains unchanged

• Becomes more efficient

What common feature do all living organisms share according to their genetic material?

• Identical gene expression patterns

• Identical DNA sequences

• The same four nucleotide bases

• The same number of chromosomes