1 - N5 Variation and Inheritance

Which of the following human characteristics shows discrete variation?

• Blood group

• Body mass

• Height

What term describes a characteristic that is controlled by more than one gene?

• Genotype

• Heterozygous

• Polygenic

What form of variation do polygenic characteristics show?

• Continuous variation

• Continuous and discrete variation

• Discrete variation

What term can be used to describe a persons eye colour or a fruit fly's wing length?

• Genotype

• Phenotype

• Polygenic

Which of the following genotypes represents a heterozygous organism?

• TT

• Tt

• tt

What name is given to different forms of the same gene?

• Alleles

• Gametes

• Genotypes

If a person inherits a dominant allele from one parent and a recessive allele from their other parent, which phenotype will they show?

• Dominant only

• Dominant and recessive

• Recessive only

The pedigree chart below shows the inheritance of the genetic condition Huntington's. Individuals affected by the condition are represented by blue shapes. All other individuals are unaffected. The allele (H) that causes the condition is dominant to the allele that leaves an individual unaffected. What are the genotypes of individuals 3 and 4?

• HH and HH

• HH and Hh

• Hh and Hh

The pedigree chart below shows the inheritance of the genetic disease Huntington's. Individuals affected by the condition are represented by shaded in shapes. All other individuals are unaffected. The allele (H) that causes the condition is dominant to the allele that leaves an individual unaffected. The genotype of individual 2 is Hh. What is the expected ratio of phenotypes in the offspring of individuals 1 and 2?

• All affected

• 3 affected: 1 unaffected

• 1 affected: 1 unaffected

In a monohybrid cross what symbol is used to illustrate the first generation of offspring?

• P

• F1

• F2