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

Polygenic Lab

Extracts from this document...


Introduction Human Height Polygenic traits are not expressed as absolute or distinct characters as was the case with Mendel's pea plant traits. Instead, polygenic traits are recognizable by their expression as a continuous variation. Height in humans is a polygenic trait. If you line up the entire class a range of variation is apparent, with an average height at the high point in the middle. Traits showing continuous variation are usually controlled by the additive effects of two or more separate gene pairs. This is what gives polygenic traits so many alleles and, therefore, so many genotypes. Usually polygenic traits are distinguished by traits usually quantified by measurement rather than counting, two or more gene pairs contributing to the phenotype, or phenotypic expression of polygenic traits varying over a wide range. ...read more.


So... If human height is a polygenic trait and polygenic traits have phenotypic variation, then human height should have a phenotypic variation. Human Ear Lobes If ear lobes are determined by a one gene trait and one gene traits have two alleles, then ear lobes are decided by two alleles making it have two genotypes. Data (Human Height) Biology class (period 3) Height (cm)(tens place) Height (cm)(ones place) 180 1,1,3 170 1,3,3,4,8 160 0,3,4,5,6,6,6,6,7,9 150 5,5,6,6,8 Biology class (period 1-3) Height (cm)(tens place) Height (cm)(ones place) Period 1 Period 2 Period 3 180 0,1,1 0,6,6,7,8,8 1,1,3 170 0,0,0,1,2,2,3,4,5,5,5 0,2,3,4,6,6,7 1,3,3,4,8 160 0,2,3,3,4,5,7,8,9,9 1,2,2,5,5,6,6,8,8,8,8 0,3,4,5,6,6,6,6,7,9 150 4,7,9 7,7 5,5,6,6,8 10 people Height (cm)(tens place) ...read more.


where a simple height gene has mutated and is present in many copies (alleles) and all alleles contributing to the height. There are so many alleles controlling this one trait that when they all get mixed up lots of outcomes are available. Human Ear Lobes My hypothesis that stated, if ear lobes are determined by a one gene trait and one gene traits have two alleles, then ear lobes are decided by two alleles making it have two genotypes, was true. If ear lobes are only determined by one gene then there are going to be two alleles. There is not a very big variation in the ear lobes because it is one gene trait, so no matter how you arrange the two alleles one is going to be dominant and one is going to be recessive, making only two outcomes. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology 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 International Baccalaureate Biology essays

  1. IB Genetic Lab

    length of arm-span and height of females from age 5 to 50 in centimeters collected from personal surveys The mean for the length of arm-span and height can be calculated using the following equation: Let A represent the average length of arm-span of females. Let B represent the average height.

  2. Human variation

    18.5 161.0 19 20.2 159.2 7 19.0 168.4 20 20.2 165.0 8 19.0 163.0 21 20.3 164.0 9 19.0 157.5 22 20.5 168.5 10 19.0 166.5 23 20.5 170.0 11 19.0 164.3 24 20.5 167.0 12 19.0 172.5 25 21.0 172.0 13 19.1 172.2 26 21.5 175.5 Table 3.

  1. Simpson Diversity Lab

    DATA COLLECTION: Table 1: Number of plant species found in both fields: Field Quadrat Species Rugby 1 - 10 dandelions (� 2) - 6 plantain (� 1) - 2 crab grass (� 1) - 4 unknown (� 1) 2 - 12 dandelions (� 2)

  2. IB Genetic Unit Notes

    has the recessive allele XH Xh - The term carrier can be applied to any individual that is heterozygous for a recessive

  1. Genetic Variation

    Some more barriers include addition, removal, temporal, reproductive, and behavioral. An example of this may be in reproductive barriers in which two species cannot mate because of differences on a reproductive base. In small populations, random changes in the frequency of alleles refer to genetic drift.

  2. Should Animals have the same rights as Humans? Both animals and humans exhibit behaviours ...

    This can be seen by the trend in the table which shows that eventually zero drops of saliva are produced in response to the metronome. Time Conditioned Stimulus Salivary Secretion in drops during 30 seconds 12:07 pm Metronome 13 None of the stimuli were reinforced 12:10 pm Metronome 7 12:13

  1. Comparing the Sexy Sons Hypothesis and the Pathogen Avoidance Models Effects on Sexual Selection

    Mice release certain proteins in their urine call MUPs (Major Urinary Proteins) as social pheromones for attracting females. This process has been studied for a long time with more and more evidence confirming its reliability as a measure of attractiveness (Kumar, et al.

  2. Biotechnology Assignment: Genetic Screening/Testing

    The human genome is believed to contain around 20,000-25,000 genes. In addition to studying chromosomes to the level of individual genes, genetic testing/screening in a broader sense includes biochemical tests for the possible presence of genetic diseases, or mutant forms of genes associated with increased risk of developing genetic disorders.

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