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Patterns of inheritance GapFill

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C
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The  populationgene poolgenotypeallelotype of an organism is all the genetic information of that individual. It consists of a number of different genes, which may come in different forms, called  allelesgenomeschromatidsgenotypes. If, for a certain characteristic, an individual possesses two variants which are different, they are referred to as  heterozygoushomologousautosomalcodominant for that trait.

Some gene variants may only be expressed in the absence of a dominant variant - they are called  non-expressivecooperativesubmissiverecessive. In the case that more than one gene variant can contribute to the phenotype, they are referred to as  cooperativecodominanthomologousintegrative.  HypostasisCodominanceEpistasisGenetic drift occurs when one gene affects the expression of another.

Some genes are found only on the X chromosome or the Y chromosome, and are called  dihybridcodominantepistaticsex-linked.

A  simple regression calculationPearson correlation coefficientchi-squared teststudent's t-test can be used to test whether the observed phenotypic ratios from genetic crosses differ significantly from the expected ratios. To do this, you need to know what the correct  phenotypic rationull hypothesisdegree of freedomcritical value to use is, which is the number of classes minus one.

The major source of genetic variation within a population is from mutation, but sexually reproducing organisms also vary as a result of  mitosishydrolysismeiosisinversion and  random fertilisationcondensationnucleationcross-contamination of gametes. Many continuous characteristics may be determined largely by genes, but also influenced by  genomeenvironmentsex-linkageepistasis.

In small populations, changes in allelic frequencies are likely to quickly have a huge effect on the whole population; this is known as  mutant accumulationgenotype innovationspecies diversificationgenetic drift. Reproductive separation may occur as a result of a physical barrier - this geographic separation is known as  boundarytopographicforeignallopatric speciation. Alternatively,  parapatricsympatricnon-divisivehabitual speciation occurs when populations in the same region become reproductively separated for another reason.

This is your 1st attempt! You get 3 marks for each one you get right. Good luck!

Pass Mark
72%