Question

question 54
selective breeding is when humans...
a breed organisms for desired traits
b produce clones in a lab
c sort organisms by phenotype
d edit dna directly using enzymes

question 55
selective breeding relies on...
a each organism having identical dna
b naturally occurring genetic variation
c mutations created only by radiation
d engineered traits in the laboratory setting

Explanation:

Question 54

• Option a: Selective breeding is the process where humans intentionally breed organisms to get offspring with desired traits (like breeding dogs for specific sizes or temperaments).
• Option b: Producing clones in a lab is cloning, not selective breeding.
• Option c: Sorting by phenotype is just classification, not breeding for traits.
• Option d: Editing DNA directly with enzymes is genetic engineering (like CRISPR), not selective breeding.

• Option a: Organisms don't have identical DNA (except clones), and selective breeding uses genetic differences.
• Option b: Selective breeding depends on the natural genetic variation within a population. Humans choose organisms with desired traits (from this natural variation) to breed.
• Option c: Mutations from radiation are induced mutations, and selective breeding uses existing natural variation, not just radiation - induced mutations.
• Option d: Engineered traits in a lab are genetic engineering, while selective breeding uses natural breeding with existing traits.

Answer:

a. breed organisms for desired traits

Question 55