Continuous + discontinuous variation - Representing variation genetically

Question 1

What is continuous variation?

Answer 1

Features can be measured across a range

Data collected is quantitative

Question 2

What is discontinuous variation?

Answer 2

Features form distinct classes or categories

Data collected is qualitative

Question 3

What is the gene locus of continuous + discontinuous variation?

Answer 3

Continuous = Many loci, may be on different chromosomes

Discontinuous = Usually only 1 but may be small number

Question 4

What are the number of alleles in continuous + discontinuous variation?

Answer 4

Continuous = Many pairs of alleles since many genes contribute to inheritance (polygenic)

Discontinuous = 1 pair of alleles (monogenic) or small number

Question 5

What are the effects on phenotype in continuous + discontinuous variation?

Answer 5

Continuous = Many intermediate phenotypes between extremes

Discontinuous = Feature either present or absent

Question 6

Which variation does environmental influence have the biggest impact on?

Answer 6

Continuous variation

Question 7

What are examples of continuous + discontinuous variation?

Answer 7

Continuous = Height in humans

Discontinuous = Human blood groups

Question 8

How do we represent continuous + discontinuous variation?

Answer 8

Continuous = Histogram or normal distribution curve

Discontinuous = Bar graph