Chapter 10 Biology

• what is the taxonomic hierarchy of classification 


  Domain

  Kingdom

  phylum

  class

  order

  family

  genus

  species
• Advantages of binomial system of naming species 


  To predict characteristic to identify species and to find evolutionary links as well as being able to be used and understood by scientists world wide
• Features used to classify organisms into prokaryotae


  Unicellular

  no nucleus or other membrane bound organelles

  small ribosome

  no visible feeding mechanism

  nutrients absorbed or produced internally by photosynthesis
• Features used to classify organisms into Protoctista 


  Mainly unicellular

  Has a nucleus and other membrane bound organelles

  some have chloroplasts

  some are sessile but others moves by cilia or flagella

  nutrients acquired by photosynthesis or ingestiob of other organisms auto Or heterotrophic
• Features used to classify organisms into Fungi 


  Uni or multi cellular

  nucleus and membrane bound organelles and cell wall composed of chitin

  no chloroplasts or chlorophyll

  no mechanisms for moving

  body made of hyphae

  saprophytic feeders absor decaying matter

  store food as glycogen
• Features used to classify organisms into plantae


  Multicellular

  nucleus and membrane organelles including chloroplasts and cell wall made from cellulose

  ALL contain chlorophyll

  most don’t move but some plant gametes can move with cilia or flagella

  nutrients only from photosynthesis

  store food as starch
• Features used to classify organisms into animalia 


  Multicellular

  no cell walls

  no chloroplasts

  move with aid of cilia flagella or contractile proteins in the form of muscular organs

  heterotrpoptic - nutrients aquired by ingestion

  store food as glycogen
• 3 domains

  Eukarya- 80s ribosomes

  archaea - 70s ribosomes rna contains 8-10 proteins

  bacteria - 70s ribosomes RNA contains 5 protons
• Relationship between phylogeny and classification 


  Classification is based more on features whereas phylogeny is more evolutionary history
• In a phylogenetic tree what do closer branches mean 


  Closer related
• What do nodes show 


  Common ancestors
• Evidence for the theory of evolution by natural selection

  Variation

  struggle for existence

  advantageous characteristics survive to reproduce

  genes passed on so advantageous phenotype becomes more prevalent
• Contributions from Wallace and Darwin

  Wallace sent his workings to Darwin and they were similar Darwin went to the Galapagos island and studies finches beaks and sent and preserved specimens for other scientists to look at
• Evidence for evolution?

  paleontology

  comparative anatomy

  comparative biochemistry
• palaeontology 


  Study of fossils
• Comparative anatomy 


  similarities and differences between organisms anatomy
• comparative biochemistry 


  Similarities and differences between the chemical makeup of organisms
• Extinct 


  Dead
• Extanct


  Alive
• Homologous structure suggest what 


  Common ancestor
• Disadvantages of fossil records 


  Many organisms are soft bodied and decompose before they fossilate
• Intraspecific variation?


  Variation between members of the same species
• Interspecific variation 


  Variation between members of different species
• Difference between discontinuous and continuous variation 


  Discontinuous variation is where there are set values or categories in which data fall into. Continuous variation however can take on any value from one extreme to the other.
• Examples of continuous variation 


  Height, weight, length
• Examples of discontinuous 


  Type of plant xerophyte hydrophyte animal classification
• Causes of genetic variation

  Alleles - recessive and dominant and parent

  mutations - changes in dna codes for different proteins

  Meiosis - genetic content from each parent is mixed up before the nucleus divides and then the crossing over

  sexual reproduction - which alleles from each parent becomes phenotypes

  chance - which gametes form
• Causes of environmental variation


  access to sun for growth as plants can not move

  In animals scars as they can not be inherited from your parents
• What is Students T test used for 


  It is used to compare the means of data values of 2 populations
• What is a null hypothesis 


  Prediction that there is no significant difference and so it just chance
• If calculated t value is above tabled value what does this mean 


  We can reject the null hypothesis as there is a reason for the difference and it is not just chance
• Anatomical adaptations 


  Physical features internal/external
• Behavioural adaptations 


  The way an organism acts either inherited or learnt
• Physiological adaptations

  Processes that take place inside the organism
• Types of anatomical adapatations 


  Camouflage

  body covering

  teeth

  mimicry
• Types of behavioural adaptations

  Migration

  hibernation

  courtship

  survival behaviour
• Types of physiological adaptations 


  Poison production

  antibiotic production

  water holding
• Why could organisms from different taxonomic groups have similar anatomical features 


  As they come from a common ancestor but as a result of divergent evolution became new species despite having similar features
• Evolution of pesticide resistance in insects and drug resistance in microorganisms 


  Resistance comes from less resistant bacteria is killed off leaving higher resistant ones which can reproduce a-sexually to produce even more resistant bacteria which eventually through evolution becomes so resistant that a drug or pesticide can not kill it