• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Sex linkage in fruit flies and huntingdons disease

Extracts from this document...


In fruit flies the eye colour trait is determined by the sex chromosome. There are two sex chromosomes, X and Y; XX indicates the individual is a female and the XY indicates being male. The sex chromosome include other genes that determine other traits. When these genes are positioned on a sex chromosome, they are named as sex-linked genes. The eye colour gene for fruit flies are solely found on the X chromosome because it is much bigger in size when compared to the Y chromosome; therefore, the genetic information found on the X chromosome is much more than the Y chromosome. As female flies have a double copy of the eye colour gene, one on each of the X chromosome and male flies have one copy of the eye colour gene on the X chromosome, therefore that one copy gene will show up whichever allele he inherits from the mother flies. ...read more.


and 25% have red eyes (XRY-); 25% of female offsprings have white eyes (XrXr) and 25% have red eyes (XRXr). As the males can inherit only one eye colour allele, which is from the mother and she had both dominant (XR) and recessive (Xr) eye colour alleles, 50% showed up as white eye colour and 50% showed up as red eye colour. Whereas the females inherit both alleles, one from the mother and one from the father. In all cases the father passed down the recessive allele (Xr) and the mother passed down the dominant (XR) and recessive (Xr). 50% of the females are all carriers and their eye colour shows up as red, due to the mother passing down her (XR) allele and the father passing down his (Xr) allele. The rest of the females have white eyes due to the father passing down his (Xr) ...read more.


Colour blindness? most common form is named the red/green colour blindness. Red/green colour blindness sufferers mix up all the colours that have some red and/or green as part of the entire colour. For example they will see pink as white as they view red colour component is separated from the pink. According to the punnet square results only 25% of the offspring?s will have neither of the disorders and 75% will have at least one of them. Therefore, if the couple want to have a child of their own it is a risk worth taking. Their other option is to have In Vitro Fertilisation (IVF) treatment done as this allows the egg and the sperm to be fertilised outside the body, this way the traits that are being passed down could be tracked and determined to give birth to a healthy child. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Genetics, Evolution & Biodiversity section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Genetics, Evolution & Biodiversity essays

  1. Research on mad cow disease and creutzfeldt-jacob disease

    3 So to sum up the symptoms: > Early stages - Mood wings, Memory lapses, Loss of interest in social activities, Impaired ability to work > Middle Stages - Loss of balance, Poor vision, Slurred speech > Late Stages - Loss of movement and speech completely, involuntary muscle contractions and

  2. AIDS - a man-made disease?

    Parallel to this syndrome, disorders in various organ systems occur, the most severe in the brain, the symptoms of which range from motoric disorders to severe dementia and death. This set of symptoms, say the Segals, is identical in every detail with the Visna sickness which occurs in sheep, mainly in Iceland.

  1. Investigating the colour variation of Littorina littoralis and their abundance across the upper, middle ...

    It was also predicted that throughout the stretch of the rocky shore, a higher proportion of Littorina littoralis will have dark coloured shells. The majority of the rocky shore is covered in dark grey coloured rocks, and wet sand. The Littorina littoralis with shell colours of grey or black will

  2. Parkinsons Disease

    such as sweating, breathing etc. * Difficulties with sleeping * Weight loss- there is a generally decreased appetite associated with PD. This may largely be due to swallowing difficulties and other gastrointestinal disturbances8 * Pain * Depression & Anxiety- anxiety disorders occur in up to 40% of patients with Parkinson's disease (PD)9.

  1. The Biology of Autistic Spectrum Disorder and the Social Implications

    However, it is about integration, with adequate support and training. Segregating autistic children may also have the same effect as autistic children grow older because of that feeling of not fitting in with society. What the Make Schools Make Sense Report Concluded Every child has the potential to learn and

  2. Evaluating generations of fruit flies for inherited characteristics.

    from the male parent, resulting in large wings. Two offspring will inherit one dominant allele (A) from the mother and a recessive allele (a) from the father fly, resulting again with large wings. Finally, one of the offspring will inherit both recessive alleles (aa)

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work