variation

• variations can be caused by two key factors...?


  genetics and enviorment.
• what is genetic variation?

  Differences in DNA inherited from parents. (such as the shape of earlobes, female or male, eye colour, and blood groups)
• what is Environmental variation?


  differences in the environmental conditions have led to variation (acquired characteristics) e.g. scars from injury, hair length, accents, tattoos, language spoken (Caused by external factors )
• what is genetic variation caused by?


  sexual reproduction

  mutations
• what is discontinuous variation?


  discontinuous variation is when there is a limited number of values that an individual can possess. the individuals fall into distinct categories and is based on features that cannot be measured. foe e.g tongue rolling
• what is continuous variation


  in continuous variation the range of measurements goes from one extreme to the other to generate continuous data. e.g. human height
• why does mutation happen?


  mutation happens all the time due to cell division and environmental factors.
• examples of genetic variation caused by mutation includes:


  lobed vs attached ear lobes

  straight vs hitchhikers' thumb

  rolled vs non rolled tongue
• what is variation?

  variation refers to the differences in characteristics between individuals of the same species. It can be caused by genetic factors (inheritance) or environmental factors.
• what does mutation mean?

  mutation is a change in the DNA sequence of an organism that can lead to a new phenotype