Mechanisms that Produced Change in Populations

• Evolution, the gradual process of change, is naturally occurring among populations at negligible rate.
• mechanisms that produce change in populations from generation to generation; natural selection,Artificial selection,Genetic Drift,Mutation, and, Recombination
• Hardy- Weinberg Principle which states that the allele frequencies in population will remain constant unless one or more factors caused these frequencies to change. When allele frequencies remain, constant there is genetic equilibrium, thus, the population will not evolve.
• who introduced the natural selection?

  charles darwin
• what mechanism is an evolution process which hypothesize that all forms of life came from a common ancestry which developed into various forms as they adapted to their environment?

  natural selection
• the natural selection theory summarizes the famous evolutionary context “survival of the fittest”
• Natural selection results in the accumulation of new variations and the loss of unfavorable ones, giving rise to new species.
• artificial selection has the other term preferred by farmers and genetic engineers called?


  selective breeding
• what mechanism describes random fluctuations in allele frequencies in a population?

  genetic drift
• It is a permanent change in the DNA sequence of a gene ?

  mutation
• It is a process by which pieces of DNA are broken and recombined to produce new combinations of alleles populations?

  recombination
• It is also called "selective breeding”, where humans select for desirable traits in agricultural products or animals?

  artificial selection
• One example of genetic drift is a Bottleneck effect which may happen when the size of a population is severely reduced.
• mutations have two general types which is?

  1. DNA MUTATIONS 2. CHROMOSOMAL MUTATIONS
• what are the other names of chromosomal mutations?

  chromosomal abnormalities and chromosomal aberrations
• when does dna mutations occur?

  when there are changes in the nucleotide sequence
• when does the chromosomal mutations occur?

  when there are changes in the structure and number of chromosomes
• when does recombinant mechanism occur?


  during the meiosis in eukaryotic cells
• crossovers results to recombination
• what condition by hardy-weinberg principle does this belong?No new alleles are generated by mutation nor are genes duplicated or deleted

  no mutation
• Organisms mate randomly with each other with no preference for particular genotypes?

  random mating
• Neither individuals nor their gametes will enter or exit the population?

  no gene flow
• The population should be effectively infinite in size?

  very large population size
• All alleles that confer equal fitness tend to make organisms likely to survive and reproduce and those alleles with reduced fitness tend to have a dropping frequency from one generation to the next?

  no natural selection
• what following conditions did Hardy-Weinberg principle make?

  No mutation , Random mating, No gene flow, Very large population size, and No natural selection