Lesson Worksheet: Variation Biology

In this worksheet, we will practice recalling examples of genetic and environmental variation and distinguishing between characteristics that show continuous or discontinuous variation.


The graph shows the percentage of a population of plants with a given number of flowers. What type of variation is the number of flowers?

  • AContinuous
  • BDiscontinuous


A group of scientists want to investigate the effect of different soil conditions on plant growth. They cloned a plant to get a total of 7 plants and grew them in different nitrate concentrations for 14 days. They then repeated this with a different species of plant. The table given shows their results.

Nitrate Concentration (ppm)Overall Plant Growth (mm) Species 1Overall Plant Growth (mm) Species 2

The scientists cloned the plants so they were genetically identical. Which of the following best explains why this was important?

  • ABecause the plants would all grow the same amount
  • BBecause any changes in growth would be due to environmental variation alone
  • CBecause any changes in growth would be due to genetic variation alone
  • DBecause the plants all looked the same

Which of the following conclusions is correct, based on the data given?

  • APlant growth is due to genetic and environmental factors.
  • BPlant growth is due to environmental factors alone.
  • CPlants of the same species will grow the same amount, no matter where they are grown.
  • DPlant growth is due to genetic factors alone.

Is plant growth an example of continuous or discontinuous variation?

  • ADiscontinuous
  • BContinuous


What is the correct key term for the variation that is caused by where an organism lives and what it interacts with?

  • AEnvironmental variation
  • BGenetic variation
  • CEpidemic variation
  • DExternal variation


Give the correct key term for the differences in the characteristics of organisms.

  • AVariation
  • BPhenotypes
  • CGenotypes
  • DSymptoms
  • EDifferentiation


Give the correct key term for the variation that is caused by differences in alleles that are inherited or caused by mutations.

  • AGenetic variation
  • BGeneric variation
  • CEnvironmental variation
  • DMutagenic variation


Give the correct key term for the physical characteristics of an organism.

  • AGenotype
  • BGenome
  • CVariation
  • DMorphology
  • EPhenotype


The graph given shows the frequency of different stem lengths in a population of plants.

What type of variation does this graph show?

  • AContinuous
  • BDiscontinuous

Which of the following best explains how this graph shows a normal distribution?

  • AThe mean is the same as the median and the mode.
  • BThe mean, median, and mode are all different values.
  • CThe mean is larger than the median.
  • DThe mode is smaller than the median.

Variations in the stem length can be caused by mutations. Which of the following correctly defines mutations?

  • AChanges in the sugar–phosphate backbone of DNA
  • BChanges in the phenotype
  • CA section of DNA that codes for a protein
  • DChanges in the DNA base sequence


Variation can be grouped into two types: continuous and discontinuous. For the following statements, choose the correct type of variation to fill the gap.

variation is when the data can only take a limited set of values.

  • AContinuous
  • BDiscontinuous

variation is when the data can be any value within a given range.

  • ADiscontinuous
  • BContinuous

variation is controlled by genetic and environmental factors.

  • ADiscontinuous
  • BContinuous

variation is usually controlled by genetic factors alone.

  • ADiscontinuous
  • BContinuous

Practice Means Progress

Boost your grades with free daily practice questions. Download Nagwa Practice today!

scan me!

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.