Biology Genetics & Evolution Flashcards

What does the Hardy-Weinberg principle predict about allele frequencies in a population?

Answer: They remain constant in the absence of evolutionary forces

The Hardy-Weinberg principle states allele and genotype frequencies remain constant across generations in a non-evolving population.

Which stage of meiosis results in genetic recombination via crossing over?

Answer: Prophase I

Crossing over between homologous chromosomes occurs during Prophase I of meiosis, generating new allele combinations.

A gene has two alleles with frequencies p = 0.6 and q = 0.4. Under Hardy-Weinberg equilibrium, what is the expected frequency of heterozygotes?

Answer: 0.48

Heterozygote frequency = 2pq = 2 × 0.6 × 0.4 = 0.48.

What distinguishes microevolution from macroevolution?

Answer: Microevolution is changes in allele frequency within a species; macroevolution is species-level divergence and above

Microevolution refers to allele frequency changes within a population, while macroevolution encompasses speciation and higher-level evolutionary changes.

Which mutation type results in an amino acid change that may or may not affect protein function?

Answer: Missense mutation

Missense mutations change one codon to code for a different amino acid, which may or may not impact protein function depending on the change.

What is the role of restriction enzymes in recombinant DNA technology?

Answer: They cut DNA at specific sequences

Restriction enzymes recognize specific DNA sequences and cleave the DNA at or near those sites, enabling gene cloning and manipulation.

Which concept explains why islands often have unique species found nowhere else on Earth?

Answer: Geographic isolation leading to independent speciation

Islands are geographically isolated, so colonizing populations evolve independently over time, producing endemic species through allopatric speciation.