bio unit 2

• What is classification based on?

  Information available at the time
• Why is classification described as tentative?

  It changes with new information
• How many species of Gentoo penguins were revealed in 2020?

  Four species
• What defines a species?

  A group that can interbreed and produce fertile offspring
• What does classification involve?

  Dividing organisms based on evolutionary relationships
• What does hierarchical classification mean?

  Large groups are split into smaller groups
• What does phylogenetic classification indicate?

  Organisms in the same group are closely related
• What is a taxon?

  A group in biological classification
• What is the structure of a binomial name?

  Two parts: genus and species
• How is the first part of a binomial name formatted?

  It is capitalized
• Why are binomial names important?

  They avoid issues with local names
• What did studies of ribosomal RNA suggest in 1977?

  There should be three domains
• What is a domain in biological classification?

  A larger taxon than a kingdom
• What are the three domains of life?

  Eubacteria, Archaea, Eukarya
• What characterizes Eubacteria?

  They are the 'true' bacteria
• What are Archaea known for?

  Being extremophiles
• What defines Eukarya?

  All eukaryotic organisms
• What are extremophiles?

  Organisms living in harsh environmental conditions
• What are the taxonomic groups in order from largest to smallest?

  Kingdom, Phylum, Class, Order, Family, Genus, Species
• What are the five kingdoms and their characteristics?

  • Prokaryotae: Lack nucleus, have circular DNA
  • Animalia: Multicellular, no cell wall, heterotrophic
  • Plantae: Multicellular, photosynthetic, cell wall of cellulose
  • Fungi: Heterotrophic, cell wall of chitin, reproduce by spores
  • Protoctista: Mostly unicellular, no tissue differentiation
• What does morphology refer to in biological classification?

  Shape and form of an organism
• What is convergent evolution?

  Unrelated organisms develop similar morphology
• What is polymorphism in a species?

  Presence of multiple forms within a species
• What are homologous structures?

  Structures with the same origin but different functions
• How is polymorphism assessed at a genetic level?

  By determining the number of alleles present
• What does a higher variation in alleles indicate?

  Higher genetic diversity in the population
• What are analogous structures?

  Structures with the same function but different origins
• What does biodiversity refer to?

  Different species and their abundance in an area
• How does biodiversity vary spatially?

  Biodiversity increases closer to the equator
• How can biochemical evidence establish relatedness?

  By comparing sequences of biological polymers
• What do mutations in DNA lead to?

  Differences in amino acid sequences of proteins
• What is a molecular clock?

  A timeline showing when mutations occurred
• What is gel electrophoresis used for?

  To separate DNA and protein fragments
• What does a DNA fingerprint represent?

  A banding pattern for comparison
• How does biodiversity vary temporally?

  Biodiversity changes over time due to events
• What do phylogenetic trees represent?

  Evolutionary pathways leading to different species
• What does the axis of a phylogenetic tree represent?

  Time moving forward
• What human activities affect biodiversity?

  Habitat destruction and climate change
• What does each junction in a phylogenetic tree represent?

  A common ancestor for the branches
• What does it mean if two organisms share a recent common ancestor?

  They are more closely related