4.3 genetic diversity due to mutation and meiosis

• What is antibiotic resistance?

  Loss of bacteria's susceptibility to antibiotics
• What is a base deletion in DNA?

  Removal of one base causing potential frameshift
• What is a base substitution in DNA?

  Replacement of a base that may change amino acid
• What condition is caused by an extra 21st chromosome?

  Down syndrome
• How do populations evolve?

  Through changes in gene frequencies over time
• What is a gene?

  A section of DNA coding for polypeptides
• What is a mutagenic agent?

  A chemical or physical agent causing mutations
• What is a mutation?

  A change in a DNA base sequence
• What is nondisjunction?

  Failure of chromosomes to separate properly
• What are spontaneous mutations?

  Random mutations occurring without external influence
• What is an allele?

  Different versions of the same gene
• What is a chromatid?

  One section of DNA on a homologous chromosome
• What is a chromosome?

  A thread-like structure made of DNA and protein
• What does diploid mean?

  Having paired chromosomes from each parent
• What occurs during the first meiotic division?

  Separation of homologous chromosomes to halve chromosome number
• What are gametes?

  Reproductive cells, also known as sex cells
• What is genetic variation?

  Variation in DNA sequences among individuals
• What does haploid mean?

  Having a single set of chromosomes
• What are homologous chromosomes?

  Chromosomes that share structural features and genes
• What is independent assortment?

  Genes separate independently during gamete formation
• What is meiosis?

  A type of cell division producing haploid cells
• What is crossing over?

  Swapping of genetic material between homologous chromosomes
• What is a locus?

  A specific location on a chromosome
• What is recombination?

  Process of breaking and recombining DNA pieces
• What is a spore?

  A reproductive unit capable of forming a new individual
• What is allele frequency?

  Number of times an allele occurs in a gene pool
• What is natural selection?

  Process where better-adapted organisms survive and reproduce
• What is a population?

  Number of individuals of a species in an area
• What is variation in biology?

  Differences in DNA or protein sequences
• What is directional selection?

  Selection favoring one extreme of characteristics
• What is disruptive selection?

  Selection favoring both extremes of a distribution
• What is a normal distribution?

  A frequency distribution with a bell-shaped curve
• What is adaptation in biology?

  Process by which species fit to their environment
• What does anatomical refer to?

  Relating to bodily structure
• How does behavior affect evolution?

  It influences mating patterns and population evolution
• What is intraspecific competition?

  Competition between individuals of the same species
• What is interspecific competition?

  Competition between individuals of different species
• What is physiological adaptation?

  Normal functions of living organisms and their parts
• What is an agar plate?

  A Petri dish with a growth medium
• What is binary fission?

  A form of asexual reproduction in prokaryotes