Pros and Cons of Selection - Middle School Life Science
- What is a common genetic risk associated with inbreeding in domesticated animals?
- Higher chance of harmful recessive traits appearing. Inbreeding unmasks harmful recessive alleles in offspring.
- Which term describes editing DNA at a specific location to change a trait?
- Gene editing (for example, CRISPR). Precise DNA changes modify specific genetic sequences.
- What is cloning?
- Producing a genetically identical copy of a cell or organism. Creates exact genetic duplicates through asexual reproduction methods.
- What is a major environmental concern about gene flow from GM crops?
- Engineered genes may spread to wild relatives through cross-pollination. Modified genes could create uncontrollable wild plant hybrids.
- What is the main benefit of artificial selection in crops and livestock?
- Increases frequency of desired traits in a population. Breeding selects for beneficial traits over generations.
- Which option best describes a benefit of conserving wild gene pools for breeding?
- Provides new alleles for disease resistance and adaptation. Wild relatives contain valuable genetic variation for breeding.
- What is a major concern of selective breeding related to genetic diversity?
- Reduced genetic variation, increasing vulnerability to disease. Limited gene pool makes populations susceptible to widespread disease.
- Which option best matches this case: "Dogs bred for very short snouts often have breathing issues"?
- Concern: selective breeding can increase health problems. Extreme physical traits from selective breeding cause health issues.
- Identify the correct concern: A single high-yield crop variety replaces many local varieties.
- Concern: reduced genetic diversity and higher risk from disease outbreaks. Monoculture farming eliminates genetic variation needed for resilience.
- What is one potential medical benefit of gene editing in humans?
- Possible treatment or prevention of genetic diseases. Correcting disease-causing genes could cure inherited disorders.
- What is a medical benefit of gene therapy?
- It can treat genetic disorders by correcting or replacing faulty genes. Repairs genetic defects causing inherited diseases at their source.
- What is a key ethical concern about editing human embryos?
- Changes could be inherited by future generations without consent. Germline edits affect all descendants permanently.
- Identify the technology that inserts a gene from one organism into another.
- Genetic engineering (transgenic modification). DNA from different species is combined artificially.
- What term describes a sudden reduction in population size that lowers variation?
- Genetic bottleneck. Population crash dramatically reduces genetic diversity.
- What is a likely outcome when a bottlenecked population is later selectively bred?
- Even less genetic diversity and more inherited disorders. Limited gene pool amplifies negative effects of selective breeding.
- What is a major environmental concern about genes from engineered crops spreading?
- Gene flow to wild relatives, creating hard-to-control weeds. Modified genes may spread to wild plants uncontrollably.
- Which option best states a benefit of selective breeding for food supply?
- Higher yield and more uniform product quality. Selected traits improve crop productivity and consistency.
- What is a potential benefit of GM crops related to pesticides?
- Some GM crops reduce insect damage and can lower insecticide use. Built-in pest resistance reduces chemical pesticide applications.
- Which term describes a harmful effect when a population has too little genetic variation?
- Inbreeding depression. Low genetic diversity reduces fitness and survival.
- What is a concern about pests and weeds when a single trait is widely used?
- Resistance can evolve, making control methods less effective. Overuse of single traits accelerates natural selection for resistance.
- What term describes mating of close relatives that increases homozygosity?
- Inbreeding. Related individuals share similar genes, increasing homozygosity.
- What is inbreeding, and why is it a concern in selective breeding?
- Breeding close relatives; it raises the chance of harmful recessive traits. Related parents share more genes, doubling harmful allele expression risk.
- What is one benefit of genetically engineered crops related to pest damage?
- Reduced crop loss due to pests. Engineered resistance genes protect crops from insects.
- What is a common benefit of selective breeding in livestock?
- Increased production traits such as faster growth or more milk. Breeding selects for traits that maximize agricultural productivity.
- Which option best matches this case: "A crop is engineered to survive drought with less irrigation"?
- Benefit: genetic engineering can improve survival in harsh conditions. Engineered traits help crops thrive with limited water resources.
- Which option best states a concern of uniform crops created by selective breeding?
- Greater vulnerability to the same disease or pest. Genetic uniformity makes all plants susceptible to same threats.
- Which term describes humans choosing parents with desired traits to produce offspring?
- Artificial selection (selective breeding). Humans control breeding to enhance specific traits.
- What is genetic engineering?
- Directly changing an organism's DNA to alter traits. Uses biotechnology to modify genetic material at the molecular level.
- What is the definition of a recessive allele in inheritance?
- An allele expressed only when two copies are present. Recessive traits appear only in homozygous individuals.
- Identify the best concern statement about selecting for extreme traits in pets.
- May increase health problems linked to the selected trait. Extreme traits often correlate with genetic disorders.
- What is a genetically modified organism (GMO)?
- An organism whose DNA has been altered using genetic engineering. Contains artificially inserted or modified genes from the same or other species.
- What is selective breeding?
- Choosing parents with desired traits to increase those traits in offspring. Artificial selection based on desired characteristics across generations.
- What is a major concern of artificial selection regarding genetic diversity?
- Reduced genetic variation in the population. Selecting for specific traits reduces overall genetic diversity.